Substance Abuse (F1)
Misuse Of Alcohol And Alcohol-related Disorders
Misuse of alcohol encompasses a spectrum of maladaptive drinking behaviors ranging from hazardous consumption to alcohol dependence, leading to physical, psychological, and social harm including liver disease, neuropsychiatric disorders, and withdrawal syndromes.
Alcohol misuse refers to a spectrum of maladaptive patterns of alcohol consumption that cause clinically significant impairment or distress. The terminology has evolved over time:
- Alcohol Use Disorder (AUD) — the current DSM-5 unified term (replacing the older DSM-IV dichotomy of "alcohol abuse" vs "alcohol dependence") [1]
- Harmful use — ICD-10 term for a pattern of drinking causing damage to physical or mental health
- Dependence syndrome — ICD-10/ICD-11 term describing a cluster of physiological, behavioural, and cognitive phenomena (tolerance, withdrawal, compulsion, loss of control, continued use despite harm, neglect of other activities)
- Alcoholism — a colloquial, non-diagnostic term still widely used clinically
Breaking down the key term: "alcohol" derives from Arabic al-kuḥl (originally meaning a fine powder, later applied to distilled spirits); "misuse" implies a pattern beyond social/recreational use that leads to harm.
Spectrum of Alcohol Use
Think of alcohol problems as a continuum: social drinking → hazardous drinking (at-risk but no current harm) → harmful drinking (demonstrable damage) → alcohol dependence (physiological and psychological reliance). A patient can sit anywhere on this spectrum, and movement is bidirectional.
Epidemiology
- Alcohol is the 7th leading risk factor for death and disability globally (GBD 2016 data, confirmed in 2019 updates)
- Contributes to > 3 million deaths/year (5.3% of all deaths worldwide) — WHO Global Status Report on Alcohol and Health
- Responsible for > 200 disease and injury conditions
- Heavy episodic drinking (binge drinking) prevalence ~18.2% globally among drinkers
These HK-specific figures are frequently tested.
- 23.7% drank alcohol occasionally, 9.4% at least once/week, 61.6% non-drinkers [2]
- 66.5% usually drink beer, 19.6% table wine, 10.6% Chinese rice wine, 6.9% spirits [2]
- Among drinkers, M:F ≈ 2:1; 7.2% were binge drinkers [2]
- 16.9% reported drinking beyond daily limit. 5.8% exhibited signs of drunkenness [2]
- Alcohol-related deaths contributed to 0.14% of deaths (58 in 2009) [2]
- Males consistently have higher rates of AUD (2–3× females) — this gap is narrowing in younger cohorts
- Peak onset of AUD: late teens to mid-20s
- Women develop alcohol-related organ damage (liver, brain, cardiomyopathy) at lower cumulative doses and shorter durations than men — the so-called "telescoping effect"
Why are women more susceptible? Two key reasons [2]:
- Lower total body water (proportionally more adipose tissue) → higher blood alcohol concentration (BAC) for the same dose per kg
- Lower gastric alcohol dehydrogenase (ADH) activity → less first-pass metabolism → more ethanol reaches systemic circulation
Risk Factors
Biological Factors
- Genetic predisposition plays a substantial role (heritability ≈ 50%) [2]
- Family/twin studies: MZ > DZ concordance rate, ↑ in adopted descendants of alcoholics [2]
- Cloninger subtypes: [2]
- Cloninger Type 1: later age of onset, only mildly genetic, occurs in both M + F, associated with anxious/harm-avoidant personality
- Cloninger Type 2: earlier age of onset, strongly genetic, occurs predominantly in M, associated with criminality and sociopathic disorder, novelty-seeking personality
- Key genes include: [2]
- Alcohol metabolism enzymes: ALDH2 (aldehyde dehydrogenase) inactivating mutation — much more common in Asians and associated with ↓ risk of alcohol dependence [2] — this is the so-called "Asian flush" variant (ALDH2*2), which causes accumulation of acetaldehyde → flushing, nausea, tachycardia after drinking → acts as a protective factor
- Neurotransmitter-related: GABRG1, GABRA2 (GABA_A receptor genes), COMT, DRD2 (dopamine D₂ receptor) [2]
ALDH2*2 — Hong Kong High Yield
About 30–40% of East Asians carry the ALDH22 allele. Homozygotes (ALDH22/2) almost never become alcoholics because the aversive acetaldehyde reaction is so severe. Heterozygotes have intermediate risk. This is why disulfiram works — it pharmacologically mimics what ALDH22 does genetically. However, note that ALDH2*2 carriers who DO drink are at higher risk of oesophageal and head/neck cancers (acetaldehyde is a carcinogen).
- Some biological abnormalities found to predate and predict later alcohol misuse: [2]
- ↓ Cognitive performance in some aspects, e.g. executive function, abnormal P300 visual evoked potential (VEP) [2]
- ↓ Sensitivity to acute intoxication effects of alcohol [2] — paradoxically, individuals who need more alcohol to "feel drunk" are at higher risk because they consume more before experiencing negative feedback
Psychological Factors [2]
- Associated personalities include: [2]
- Chronic anxiety, pervading sense of inferiority, self-indulgent tendencies
- Traits related to risk-taking and novelty-seeking, antisocial personality disorder
- Behaviour modelling: postulated that children of alcoholics model their behaviour on parents, but the risk seems little influenced by whether parents are currently drinking or not [2]
- Reward dependence: alcohol use leads to ↑ pleasurable feelings and ↓ anxiety → behavioural reinforcement, especially in those who ignore negative consequences (positive and negative reinforcement via the mesolimbic dopamine pathway) [2]
Social Factors [2]
- Alcohol use can be a cause or effect of other psychiatric disorders [2]
- Chronic alcohol use can precede development of major psychiatric disorders (e.g. mood disorders, psychotic disorders)
- Alcohol use can be a maladaptive response (self-medication) to ↓ distress from other psychiatric disorders
- Availability and affordability of alcohol (HK: relatively cheap, 24-hour availability in convenience stores)
- Cultural norms (drinking at business dinners, social gatherings)
- Peer pressure, social circle influence
- Occupation — high-risk occupations include hospitality, military, medical profession (access + stress)
Anatomy, Physiology, and Pharmacology of Alcohol
Understanding metabolism is critical because it underpins intoxication, withdrawal, organ damage, and drug interactions.
Step 1: Ethanol → Acetaldehyde
- Enzyme: Alcohol dehydrogenase (ADH) — primarily in gastric mucosa and hepatocytes
- Cofactor: NAD⁺ → reduced to NADH
- Also via Microsomal Ethanol Oxidizing System (MEOS/CYP2E1) — inducible with chronic use (explains metabolic tolerance)
- Also via catalase (minor pathway, in peroxisomes)
Step 2: Acetaldehyde → Acetate
- Enzyme: Aldehyde dehydrogenase (ALDH) — primarily mitochondrial ALDH2
- Cofactor: NAD⁺ → NADH
- Acetaldehyde is toxic and carcinogenic — responsible for the "flush reaction," hangover symptoms, and long-term tissue damage
Step 3: Acetate → CO₂ + H₂O
- Acetate enters peripheral tissues, converted to acetyl-CoA → enters TCA cycle
Key metabolic consequence: Chronic ethanol metabolism massively shifts the hepatic NAD⁺/NADH ratio toward NADH. This has widespread metabolic consequences:
- ↓ Gluconeogenesis → alcoholic hypoglycaemia (occurs 6–36h after ingestion of > 30g alcohol) [2]
- ↓ Fatty acid oxidation → fatty liver (steatosis)
- ↑ Lactate (pyruvate → lactate is favoured) → lactic acidosis
- ↑ Uric acid (lactate competes with urate for renal excretion) → gout
Alcohol is fundamentally a CNS depressant that acts on multiple neurotransmitter systems:
| System | Acute Effect of Alcohol | Chronic Adaptation | Relevance to Withdrawal |
|---|---|---|---|
| GABA-A | ↑ GABA-ergic (inhibitory) neurotransmission — potentiates GABA at GABA-A receptors [2] | Downregulation of GABA-A receptors (tolerance) | ↓ GABA-related inhibitory tone → hyperexcitability [2] |
| NMDA (glutamate) | Inhibition of glutamatergic (excitatory) neurotransmission via NMDA receptor blockade [2] | Upregulation of NMDA receptors [2] | Unregulated excess NMDA-related excitatory transmission [2] → seizures, autonomic storm |
| Dopamine | ↑ DA release in mesolimbic pathway (nucleus accumbens) → pleasurable effect [2] | Downregulation of DA receptors | Dysphoria, anhedonia, craving |
| Serotonin | Indirectly alters release of serotonin [2] | Serotonergic dysfunction | Mood disturbance, anxiety |
| Opioid | ↑ Endogenous opioid (endorphin) release | Opioid system dysregulation | Dysphoria |
| Norepinephrine | Indirectly alters release of NE [2] | Upregulation of adrenergic system | Autonomic hyperactivity (tremor, sweating, tachycardia, hypertension) |
The GABA-Glutamate Seesaw — Core Concept
Think of the brain as a seesaw between inhibition (GABA) and excitation (glutamate/NMDA). Alcohol acutely pushes the seesaw toward inhibition. With chronic use, the brain compensates by reducing GABA sensitivity and increasing NMDA receptors (trying to restore balance). When alcohol is suddenly removed, the seesaw swings violently toward excitation — this is why withdrawal causes tremors, seizures, and delirium tremens. This is the single most important concept in alcohol withdrawal pathophysiology.
- In HK, 1 unit of alcohol = 10g pure ethanol [2]
- Number of standard drinks = drink volume (L) × alcohol content (%vol) × 0.789 [2]
- The 0.789 factor accounts for the density of ethanol (0.789 g/mL)
- Safe drinking limit = 2 units/day (M) vs 1 unit/day (F) [2]
Practical unit estimates [2]:
| Drink | Approximate Units |
|---|---|
| 1 can of beer (330 mL, 5%) | 1.3 units |
| 1 glass of wine (125 mL, 12%) | 1.2 units |
| 1 shot of spirits (22 mL, 40%) | 0.7 units |
| 1 small glass of rice wine (20 mL, 30%) | 0.6 units |
Blood Alcohol Concentration (BAC):
- 0.1 mg/L on breathalyser corresponds to 21 mg/dL in blood [2]
- BAC of 5 mg/dL (22 µg/100 mL on breathalyser) is the driving limit in HK [2]
The aetiology of alcohol misuse is biopsychosocial — it arises from an interaction of biological vulnerability, psychological factors, and social environment [2]. No single factor is sufficient or necessary; it is the convergence of multiple factors that determines risk.
Neurobiological Basis of Addiction
The core mechanism of alcohol addiction involves the mesolimbic dopamine (reward) pathway:
- Ventral tegmental area (VTA) → projects dopaminergic neurons to the nucleus accumbens (NAc)
- Alcohol (and other substances) increase dopamine release in the NAc → subjective pleasure/reward
- With repeated exposure, neuroadaptation occurs:
- Tolerance — need more alcohol for the same reward (GABA-A downregulation, NMDA upregulation, CYP2E1 induction)
- Sensitisation of incentive-salience pathways — environmental cues associated with alcohol become powerfully motivating
- Negative reinforcement — drinking to avoid withdrawal becomes a dominant driver
- Prefrontal cortex (executive control) is progressively impaired → loss of inhibitory control over drinking behaviour
Alcoholism affects the brain front (frontal dementia), back (cerebellar vermis) and centre (corpus callosum) [2] — this elegant summary reminds us that chronic alcohol causes:
- Frontal lobe atrophy → executive dysfunction, disinhibition, personality change
- Cerebellar vermis degeneration → gait ataxia (heel-shin test abnormal > finger-nose test)
- Corpus callosum degeneration (Marchiafava-Bignami disease) → disconnection syndrome
Classification
- Episode of harmful use of alcohol — single episode causing damage
- Harmful pattern of use of alcohol — repeated pattern causing damage
- Alcohol dependence — chronic relapsing condition with compulsion, tolerance, withdrawal
- Alcohol intoxication — acute reversible syndrome
- Alcohol withdrawal — physiological syndrome upon cessation/reduction
- Alcohol-induced disorders — e.g. alcohol-induced mood disorder, psychotic disorder, neurocognitive disorder
- Alcohol Use Disorder (AUD) — mild (2–3 criteria), moderate (4–5 criteria), severe (6+ criteria out of 11)
- Alcohol intoxication
- Alcohol withdrawal
- Alcohol-induced mental disorders (specify type: depressive, anxiety, psychotic, sleep, sexual dysfunction, neurocognitive)
| Feature | Type 1 | Type 2 |
|---|---|---|
| Age of onset | Later | Earlier (before 25) |
| Genetic influence | Mildly genetic | Strongly genetic |
| Sex | Both M + F | Predominantly M |
| Personality | Harm-avoidant, anxious | Novelty-seeking, a/w criminality and sociopathic disorder |
| Alcohol-seeking behaviour | Loss of control | Inability to abstain |
| Environmental influence | Strong | Weak |
Clinical Features
The clinical features of alcohol misuse can be organised into:
- A. Acute intoxication
- B. Chronic use features (symptoms and signs of dependence)
- C. Withdrawal syndrome
- D. Long-term medical sequelae
- E. Long-term psychiatric sequelae
A. Acute Alcohol Intoxication
Clinical features are dose-dependent and relate to BAC:
| BAC (mg/dL) | Clinical Features | Pathophysiological Basis |
|---|---|---|
| 20–50 | Relaxation, mild euphoria, ↓ inhibitions | Potentiation of GABA-A in limbic system → ↓ cortical inhibition of reward pathways |
| 50–100 | Impaired coordination, ↓ reaction time, emotional lability | GABA-A potentiation + NMDA inhibition in cerebellum and motor cortex |
| 100–200 | Slurred speech, ataxia, diplopia, nausea/vomiting | Progressive cerebellar and brainstem depression |
| 200–300 | Marked ataxia, hypothermia, severe dysarthria | Brainstem depression, impaired thermoregulation |
| 300–400 | Stupor, coma | Severe generalised CNS depression |
| > 400 | Respiratory depression, death | Medullary respiratory centre depression |
Note: Tolerant individuals may show surprisingly few signs at BAC levels that would incapacitate a naive drinker. No intoxication despite ↑↑BAC can denote development of tolerance [2].
Alcoholic blackouts [2]:
- S/S: a transient amnesia lasting hours, but usually without impairment of conscious level [2]
- Reason: inhibition of NMDA receptors in hippocampus → failure of long-term potentiation (LTP) [2]
- The hippocampus requires NMDA receptor activation to consolidate short-term into long-term memories; alcohol blocks this
Alcoholic hypoglycaemia [2]:
- Occurs 6–36h after ingestion of > 30g of alcohol (moderate amount) [2]
- MoA: alcohol metabolism into acetaldehyde consumes NAD⁺ → ↑↑↑ NADH:NAD⁺ ratio in liver → insufficient NAD⁺ supply for gluconeogenesis → hypoglycaemia [2]
- S/S: confusion, aggression, stupor, coma, hypothermia → often mistaken as alcohol intoxication [2]
- Dx: hypoglycaemia is an important d/dx in confused patient with prior alcohol intake → should take H'stix before assuming intoxication [2]
- Mx: IV 50% dextrose after thiamine [2]
- Primarily supportive [2]
- IV fluid hydration to correct volume depletion and hypotension [2]
- D50 infusion if hypoglycaemia is present [2]
- 100 mg parenteral thiamine mandatory if present with coma (for prevention of B₁ deficiency) [2]
- 'Thiamine before dextrose': traditional teaching that thiamine should be given before dextrose [2]
- Benzodiazepines or first-generation antipsychotics (FGA) can be used if agitated [2]
Common Exam Mistake
Never assume a "drunk" patient is simply intoxicated. Always check blood glucose (H'stix), because alcoholic hypoglycaemia closely mimics intoxication (confusion, aggression, hypothermia). Missing hypoglycaemia can be fatal. Also consider: subdural haematoma, hepatic encephalopathy, Wernicke encephalopathy, and head injury — all common in alcoholics and all mimicking intoxication.
The ICD-10/ICD-11 dependence syndrome requires 3 or more of the following in the past 12 months. DSM-5 AUD uses a single list of 11 criteria (≥ 2 for diagnosis). The core features and their pathophysiology:
| Feature | Explanation | Pathophysiology |
|---|---|---|
| Compulsion/craving | Strong desire or sense of compulsion to drink | Sensitisation of incentive-salience in mesolimbic DA pathway; conditioned cue-reactivity |
| Difficulty in controlling use | Onset, termination, or amount of drinking | Prefrontal cortical dysfunction → impaired executive control; habit formation in dorsal striatum |
| Tolerance | Need for increasing amounts to achieve same effect | GABA-A receptor downregulation, NMDA receptor upregulation, CYP2E1 induction (metabolic tolerance) |
| Withdrawal | Physical symptoms on cessation/reduction | GABA-glutamate imbalance: ↓ GABAergic inhibition + ↑ NMDA excitatory transmission |
| Neglect of other activities | Progressive neglect of alternative pleasures or interests | Reward system "hijacked" — natural rewards pale compared to drug-induced DA surges |
| Persistent use despite harmful consequences | Continued drinking despite awareness of physical, psychological, or social harm | Compulsive behaviour loop; impaired prefrontal insight and decision-making |
| Stereotyped pattern | Narrowing of drinking repertoire | Fixed drinking patterns emerge as the behaviour becomes habitual |
C. Withdrawal Syndrome [2]
Symptoms of alcohol withdrawal vary with individual (?genetic predisposition) [2]:
| Time After Last Drink | Feature | Pathophysiology |
|---|---|---|
| 6–12 hours | Tremor, anxiety, nausea, insomnia, sweating, tachycardia | Noradrenergic and glutamatergic overactivity; ↓ GABAergic tone |
| 12–24 hours | Alcoholic hallucinosis (visual/auditory hallucinations with clear sensorium) | Cortical hyperexcitability (NMDA upregulation) without global confusion |
| 12–48 hours | Withdrawal seizures (generalised tonic-clonic) | NMDA hyperexcitability + loss of GABA-mediated seizure threshold; often in patients with "kindling" from repeated withdrawals |
| 48–72 hours | Delirium Tremens (DT) — the most severe form | Full-blown excitotoxic state with autonomic storm |
- Onset: typically 48–72 hours (but can occur up to 5–7 days) after last drink
- Classic triad: Confusion (delirium with fluctuating consciousness), Tremor (coarse), Autonomic hyperactivity (fever, sweating, tachycardia, hypertension)
- Other features: vivid visual hallucinations (classically small animals/insects — "Lilliputian hallucinations"), paranoid ideation, agitation, insomnia
- Mortality: 5–15% untreated (historically up to 35%); < 1–2% with modern ICU care
- Risk factors for DT: previous DT/withdrawal seizures, comorbid illness, older age, heavy prolonged drinking, high BAC at presentation, electrolyte abnormalities
- Kindling effect: each successive withdrawal episode tends to be more severe than the last — NMDA receptor upregulation becomes progressively more exaggerated with repeated withdrawal-reinstatement cycles
Chronic alcohol causes damage through multiple mechanisms:
- Direct toxicity (ethanol and acetaldehyde are directly cytotoxic)
- Nutritional deficiency (B1/thiamine, B3/niacin, B6, B12, folate, zinc, magnesium)
- Metabolic disruption (NAD⁺/NADH ratio, oxidative stress, lipid metabolism)
- Immune dysregulation (↓ immune function → infections)
| System | Condition | Mechanism |
|---|---|---|
| Liver | Steatosis → Steatohepatitis → Fibrosis → Cirrhosis → HCC | Shifted NAD⁺/NADH ratio → ↓ fatty acid oxidation → fat accumulation; acetaldehyde-protein adducts → immune-mediated hepatocyte injury; stellate cell activation → collagen deposition |
| GI | Oesophageal varices, Mallory-Weiss tears, gastritis/peptic ulcer, pancreatitis (acute and chronic), oesophageal carcinoma | Portal hypertension (varices); direct mucosal irritation (gastritis); acetaldehyde is a group 1 carcinogen (oesophageal Ca); pancreatic duct protein plugging → calcification |
| CVS | Alcoholic cardiomyopathy (dilated), AF, hypertension | Direct myocardial toxicity (acetaldehyde); holiday heart (binge → AF due to autonomic surge and direct electrophysiological effects); chronic sympathetic activation |
| Haem | Macrocytosis (↑MCV), folate deficiency megaloblastic anaemia, sideroblastic anaemia, thrombocytopenia, leucopenia | Folate malabsorption/↓intake → megaloblastic change; direct marrow suppression; ↑MCV also from direct membrane effect of ethanol on erythroblasts |
| Endocrine | Pseudo-Cushing syndrome, hypogonadism (gynaecomastia, testicular atrophy), hypoglycaemia | ↑ CRH/cortisol; ↑ aromatisation of androgens → oestrogens in liver + direct gonadal toxicity; ↓ NAD⁺ for gluconeogenesis |
| MSK | Myopathy, osteoporosis, gout | Direct myotoxicity; ↓ osteoblast activity + ↑ osteoclast activity; ↑ uric acid (lactate competes for renal tubular excretion) |
| Neurological | See below (major section) | Multiple mechanisms — direct toxicity, nutritional deficiency, excitotoxicity |
Neurological Complications (High Yield — "6 Causes of Confusion in Alcoholism") [1]
The lecture specifically highlights "6 causes of confusion in alcoholism" [1] — this is a critical exam framework:
- Acute intoxication — GABA potentiation, NMDA blockade
- Alcohol withdrawal / Delirium Tremens — GABA/NMDA imbalance → excitotoxicity
- Wernicke encephalopathy — thiamine (B1) deficiency → impaired glucose metabolism in vulnerable brain regions (mamillary bodies, medial thalamus, periaqueductal grey, cerebellar vermis)
- Hepatic encephalopathy — ↑ ammonia (failed hepatic metabolism in cirrhosis) → astrocyte swelling, altered neurotransmission
- Hypoglycaemia — ↓ NAD⁺ for gluconeogenesis
- Subdural haematoma — falls + coagulopathy (↓ clotting factors from hepatic dysfunction + thrombocytopenia) → bridging vein tears
Wernicke-Korsakoff Syndrome — the hallmark nutritional neuropsychiatric complication:
-
Wernicke encephalopathy (acute, reversible if treated early):
- Classic triad: Confusion, Ophthalmoplegia (especially CN VI palsy → lateral rectus paralysis → diplopia), Ataxia (cerebellar vermis degeneration)
- Why these areas? Thiamine (as thiamine pyrophosphate, TPP) is a cofactor for pyruvate dehydrogenase, α-ketoglutarate dehydrogenase, and transketolase — areas with high metabolic demand and turnover (periventricular structures) are most vulnerable to energy failure
- Only ~10% present with the classic triad — have a low threshold for diagnosis
- Treatment: IV thiamine 500 mg TDS for 3 days (high-dose Pabrinex) — must be given before or with glucose
-
Korsakoff syndrome (chronic, largely irreversible):
- Develops in ~80% of untreated Wernicke patients
- Profound anterograde amnesia (inability to form new memories) + retrograde amnesia (loss of old memories, with temporal gradient)
- Confabulation — production of fabricated memories to fill gaps (not intentional lying; the brain's attempt to make sense of memory gaps)
- Why? Damage to mamillary bodies and medial thalamic nuclei — key structures in the Papez circuit of memory
- Only ~20% recover significantly even with thiamine supplementation
Other key neurological complications:
| Condition | Features | Mechanism |
|---|---|---|
| Cerebellar degeneration | Gait ataxia (wide-based), heel-shin test abnormal > finger-nose; truncal > limb ataxia | Purkinje cell loss in anterior superior vermis — combination of direct ethanol toxicity and thiamine deficiency |
| Peripheral neuropathy | Symmetric distal sensorimotor ("stocking-glove"), painful paraesthesiae, ↓ ankle jerks | Direct neurotoxicity + B-vitamin deficiency (B1, B6, B12) → axonal degeneration (dying-back neuropathy) |
| Central pontine myelinolysis (CPM) | Quadriparesis, pseudobulbar palsy, "locked-in" syndrome | Overly rapid correction of hyponatraemia → osmotic stress on oligodendrocytes in basis pontis → demyelination |
| Marchiafava-Bignami disease | Disconnection syndrome, seizures, cognitive decline | Demyelination/necrosis of corpus callosum — mechanism unclear, likely direct toxicity + nutritional deficiency |
| Alcohol-tobacco amblyopia [2] | ↓ VA with central scotoma and loss of colour vision | Heavy drinking + smoking → deficiency of thiamine or B12 → optic atrophy |
| Alcoholic dementia | Progressive cognitive decline, frontal predominance (executive dysfunction, personality change) | Multifactorial: direct neurotoxicity, repeated excitotoxic episodes (withdrawals), nutritional deficiency, vascular risk |
Never Correct Hyponatraemia Too Quickly
Never correct hyponatraemia quicker than ~10 mmol/24h [2] in an alcoholic patient. Rapid correction → osmotic demyelination syndrome (central pontine myelinolysis). The pons is particularly susceptible because of its unique vascular architecture and high oligodendrocyte density. This is irreversible and devastating.
Psychiatric comorbidity in alcoholism is very common (lifetime diagnosis occurs in 55% of alcoholics) [2]
Causation: alcoholism often co-occurs with psychiatric disorders but causation is often unclear [2]
The relationship is bidirectional, with confounding factors [1]:
- Alcoholism → Psychiatric symptoms (alcohol-induced disorders)
- Psychiatric symptoms → Alcoholism (self-medication)
- Confounding factors complicate the picture [1]
Diagnosing comorbid psychiatric disorder in alcoholics is supported by [1][2]:
- Evidence of psychiatric disorder before onset of alcohol abuse or dependence [1]
- Evidence of persistent psychiatric symptoms during extended alcohol-free periods (over 4 weeks) [1]
- First-degree biological relative has documented psychiatric disorder [1]
Specific Comorbidities [1][2]
| Comorbidity | Prevalence | Key Points |
|---|---|---|
| Mood disorders | 40% of alcoholics [2] | Depression: most common comorbidity; alcoholism may be self-medication. 4× risk of major depression in patients with Hx of alcohol dependence [2] |
| Bipolar I disorder | 60% of bipolar I patients have alcoholism [1] | Manic episodes → hyperexcitability and impulsivity → ↑ alcohol intake. Alcoholism aggravates bipolar disorder and a/w ↑ suicide rate [2] |
| Antisocial personality | 14% of alcoholics, but 80% of antisocial personality patients suffer from alcoholism [1] | Strong bidirectional association |
| Schizophrenia | 30% abuse alcohol [1] | Alcohol ↓ feeling of isolation and temporarily ↓ symptoms of anxiety/depression/insomnia. BUT ↑ psychotic symptoms and mood swings, disruptive behaviour, suicide, treatment non-compliance, drug abuse, poor clinical outcome, drug accumulation due to hepatic damage [1] |
| Anxiety disorders | 32% of alcoholics [2] | May be self-medication (anxiolytic effect). Must be distinguished from alcohol withdrawal syndrome [2] |
| Drug abuse | 20% of drug abusers are alcoholic; alcoholics are 6× more prone to become drug abusers [1] | Cross-reinforcement through shared dopaminergic pathways |
Alcohol-related mood disorders [2]:
- Moderate/heavy alcohol use can cause mood disorders
- Major depression: 4× risk in patients with Hx of alcohol dependence [2]
- Rarely easy to untangle cause and effect between mood disorder and alcoholism [2]
- Response to treatment is much less likely if comorbid alcoholism is NOT dealt with [2]
- Mx: abstinence (clears up upon abstinence but may persist for up to 4 weeks afterwards) [2]
Alcohol-related anxiety disorders [2]:
- Any form of anxiety (GAD, phobic anxiety, OCD…) while on heavy alcohol consumption [2]
- Must be distinguished from alcohol withdrawal syndrome [2]
- Mx: abstinence (subside gradually, but may persist up to 6 months) [2]
Approach to Potential Alcohol Misuse [2]
Alert to potential alcohol misuse in the following situations [2]:
- General: issues with ADL, family/work, finances, law (especially if frequent absences on Monday — because weekend binge → Monday withdrawal/hangover)
- Medical: intoxication, withdrawal, other medical consequences of alcohol
- Psychiatric: anxiety, depression, erratic moods, ↓ concentration/memory lapses, DSH/suicide
| Tool | Details |
|---|---|
| CAGE questionnaire | ↑ Sensitivity but modest specificity only [2]. 4 questions: Cut down, Annoyed by criticism, Guilty, Eye-opener (morning drink). ≥ 2 positive = screen positive. |
| AUDIT (Alcohol Use Disorders Identification Test) | ↑ Sensitivity + ↑ Specificity, probably most useful [2]. 10-item screening tool by WHO [2]. Covers consumption, dependence symptoms, and alcohol-related problems. Score ≥ 8 = hazardous drinking. |
A comprehensive drinking history should include [2]:
- Initiation: reason for drinking, triggers, when did daily drinking start
- Use: current, regular, maximal use, describe a typical day (especially note time of first drink — an early morning drink strongly suggests dependence/relief drinking)
- Signs/symptoms of dependence: compulsion/craving, difficulty in control behaviour, stereotyped behaviour, tolerance, withdrawal, persistent use despite negative consequences, neglect of other interests and activities
- Impact: physical, mental health, ADL, family, work, social relationships
- Quitting: dates and reasons of abstinence, dates and reasons of relapses, attitude
Laboratory features of chronic alcoholism include [2]:
| Test | Sensitivity | Key Points |
|---|---|---|
| ↑ GGT | 70% | Useful screening tool but non-specific, dose-related [2]. Also elevated in liver disease of any cause, obesity, medications (e.g. anticonvulsants). Normalises within 2–6 weeks of abstinence. |
| ↑ MCV | 60% | More commonly in females; strong indicator of excessive drinking (once rule out other causes); takes weeks to return to baseline after abstinence [2]. Other causes: B12/folate deficiency, hypothyroidism, liver disease, myelodysplastic syndrome. |
| ↑ CDT (carbohydrate-deficient transferrin) | Variable | More specific than GGT [2]. Ethanol interferes with glycosylation of transferrin. Particularly useful for monitoring relapse. |
| Breath/blood alcohol concentration | N/A | Only reflects current drinking [2]. Useful for acute management but not for detecting chronic misuse. |
| Other | - | LFTs (AST:ALT ratio > 2:1 is classic for alcoholic liver disease — because mitochondrial AST is released preferentially); FBC (↑MCV, ↓platelets); U&E (↓K⁺, ↓Mg²⁺, ↓PO₄³⁻); lipid profile; uric acid |
The lecture on "Alcohol and the Brain" covers [1]:
- Alcohol-related addictive problems
- Alcohol-related medical conditions and brain changes
- Alcohol-related psychiatric disorders (alcohol-induced psychiatric disorders and comorbid conditions)
- Relationship between alcohol and psychiatric disorders
- 6 causes of confusion in alcoholism
High Yield Summary
Key Concepts:
- 1 unit in HK = 10g pure ethanol; safe limits = 2 units/day (M), 1 unit/day (F)
- Neuropharmacology: Alcohol = GABA-A potentiator + NMDA inhibitor + ↑ mesolimbic DA. Chronic use → GABA-A downregulation + NMDA upregulation. Withdrawal = excitotoxic state.
- ALDH2*2 mutation is common in Asians → protective against alcoholism (flush reaction) but ↑ cancer risk if they do drink
- Cloninger Type 1 (later onset, both sexes, mild genetics) vs Type 2 (early onset, male, strong genetics, antisocial)
- Withdrawal timeline: Tremor (6–12h) → Hallucinosis (12–24h) → Seizures (12–48h) → DT (48–72h). Each successive withdrawal is worse (kindling).
- Wernicke triad: Confusion + Ophthalmoplegia + Ataxia. Give IV thiamine BEFORE or WITH glucose. Only 10% have full triad — maintain a low threshold.
- Korsakoff: Anterograde amnesia + confabulation. Mamillary bodies + medial thalamus damage. Largely irreversible.
- 6 causes of confusion in alcoholism: Intoxication, Withdrawal/DT, Wernicke, Hepatic encephalopathy, Hypoglycaemia, Subdural haematoma
- Psychiatric comorbidity in 55% of alcoholics: Depression (40%), Bipolar I (60% of bipolar patients), Antisocial PD (80% of ASPD patients), Schizophrenia (30%), Anxiety (32%)
- Diagnosing comorbid psych disorder: psychiatric disorder before alcohol onset, persistent symptoms during ≥ 4 weeks alcohol-free, FHx of psychiatric disorder
- Screening: AUDIT (best — ↑ sensitivity + specificity, 10-item WHO tool) > CAGE (↑ sensitivity only)
- Lab markers: ↑GGT (70%, non-specific), ↑MCV (60%, weeks to normalise), ↑CDT (most specific)
Active Recall - Alcohol Misuse and Alcohol-related Disorders
[1] Lecture slides: GC 161. Alcohol and the Brain From Psychiatric to Neuropsychiatric Perspectives.pdf (p2, p42–p46) [2] Senior notes: ryanho-psych.md (sections 5.1, 5.1.1; pages 96–109) [3] Lecture slides: GC 161. Alcohol and the Brain From Psychiatric to Neuropsychiatric Perspectives.pdf (general content on neuropharmacology and aetiology)
Differential Diagnosis of Alcohol Misuse and Alcohol-related Disorders
The differential diagnosis in alcohol-related disorders is not a single, neat list — it varies depending on which clinical presentation brings the patient to attention. A patient with alcohol problems can present with intoxication, withdrawal, confusion, psychosis, mood disturbance, anxiety, or cognitive decline. For each presentation, the differential is different. Let's walk through this systematically.
The key clinical question is: "What am I actually seeing — and what else could cause this?"
This is arguably the most high-yield differential in alcohol psychiatry. The lecture explicitly identifies "6 causes of confusion in alcoholism" [1]:
| # | Cause | Key Distinguishing Features | Why This Happens |
|---|---|---|---|
| 1 | Intoxication [1] | History of recent alcohol intake; slurred speech, ataxia, nystagmus; BAC elevated; resolves as alcohol is metabolised | GABA-A potentiation + NMDA blockade → generalised CNS depression |
| 2 | Delirium Tremens (DT) [1] | Onset 48–72h after last drink; fluctuating consciousness, vivid visual hallucinations, tremor, autonomic storm (fever, tachycardia, sweating, hypertension) | Abrupt loss of chronic GABA-A potentiation + unmasked NMDA hyperexcitability → excitotoxic state |
| 3 | Head injury / Subdural haematoma [1] | History of falls (common in alcoholics); focal neurological signs; may have lucid interval then deterioration; coagulopathy + thrombocytopenia increases bleeding risk | Alcoholics fall frequently + have impaired clotting factors (hepatic dysfunction) + thrombocytopenia → bridging vein tears → subdural collection |
| 4 | Metabolic disturbances (e.g. hypoglycaemia) [1] | Confusion, aggression, sweating, tremor, seizures; H'stix confirms low glucose; responds to IV dextrose | Alcohol metabolism consumes NAD⁺ → insufficient NAD⁺ for gluconeogenesis → hypoglycaemia. Often mimics intoxication exactly |
| 5 | Hepatic encephalopathy [1] | Asterixis (liver flap), fetor hepaticus, jaundice, stigmata of chronic liver disease; ↑ ammonia; often triggered by GI bleed, infection, constipation | Cirrhosis → failed hepatic clearance of ammonia → crosses BBB → astrocyte swelling (via glutamine accumulation) → cerebral oedema and altered neurotransmission |
| 6 | Wernicke encephalopathy [1] | Classic triad: confusion + ophthalmoplegia + ataxia (but only ~10% have full triad); responds to IV thiamine | Thiamine deficiency → impaired pyruvate dehydrogenase and α-ketoglutarate dehydrogenase → energy failure in metabolically active periventricular structures |
The 6 Causes — Must Know for Exams
When you see a confused alcoholic patient, you MUST systematically consider all 6 causes. The commonest exam mistake is assuming the patient is "just drunk." Every confused alcoholic needs: H'stix (hypoglycaemia), thiamine (Wernicke), assessment for head injury (subdural), liver assessment (hepatic encephalopathy), and timeline from last drink (withdrawal/DT). Multiple causes can coexist — e.g. a patient can be both hypoglycaemic AND in withdrawal AND have a subdural.
Additional differentials for confusion in alcoholics (beyond the classic 6):
| Cause | Distinguishing Features |
|---|---|
| CNS infection (meningitis/encephalitis) | Fever, neck stiffness, photophobia; immunocompromised state in alcoholics increases risk; LP needed |
| Drug overdose / polypharmacy | Urine toxicology screen; check for co-ingestion of benzodiazepines, opioids, paracetamol |
| Electrolyte disturbance (beyond hypoglycaemia) | HypoNa, hypoK, hypoMg, hypoPO₄ — all common in alcoholics due to poor intake, vomiting, and renal losses |
| Central pontine myelinolysis | Quadriparesis, dysarthria, dysphagia; history of rapid Na⁺ correction |
| Alcoholic ketoacidosis | Anion gap metabolic acidosis; occurs after binge followed by fasting; ketones elevated but glucose may be normal or low |
| Postictal state | History of witnessed seizure; gradual resolution; may occur after withdrawal seizure |
When an alcoholic patient presents with hallucinations or delusions, you must distinguish between several entities [1][2]:
| Diagnosis | Key Features | How to Differentiate |
|---|---|---|
| Alcoholic hallucinosis [1] | Chronic heavy drinkers; auditory hallucinations; in clear consciousness; distressing in content; some develop schizophrenia, some remit after stopping alcohol use [1] | Differentiate from delirium tremens: reduction in alcohol intake, clouded sensorium, visual hallucinations in DT [1]. Alcoholic hallucinosis has clear sensorium and predominantly auditory hallucinations |
| Delirium tremens | Visual hallucinations (classically Lilliputian — small animals/insects), clouded/fluctuating consciousness, autonomic storm, tremor | Onset 48–72h after cessation; clouded sensorium is the key distinguisher from hallucinosis |
| Alcohol-induced psychotic disorder (delusional) | Typically morbid jealousy (Othello syndrome) — abnormal belief partner is unfaithful; incessant cross-questioning, searching for evidence; risk of violence [2] | Content is specifically jealousy-themed; often in male chronic drinkers; other causes include schizophrenia, mood disorder, organic disorder, paranoid personality disorder [2] |
| Primary schizophrenia | Schneiderian first-rank symptoms; persistent psychosis independent of alcohol use; deteriorating function over time; FHx of psychosis | Psychotic symptoms persist > 4 weeks after abstinence; onset may predate alcohol use; negative symptoms prominent |
| Substance-induced psychosis (other substances) | Stimulants (methamphetamine, cocaine) and cannabis are common causes; urine drug screen positive | Temporal relationship with substance use; resolves with clearance of substance |
| Mood disorder with psychotic features | Psychosis is mood-congruent (e.g. nihilistic delusions in depression, grandiose delusions in mania); affective symptoms predominate | Psychotic features occur within the context of a mood episode |
Diagnosing a comorbid primary psychiatric disorder in an alcoholic is supported by [1]:
- Evidence of psychiatric disorder before onset of alcohol abuse or dependence [1]
- Evidence of persistent psychiatric symptoms during extended alcohol-free periods (over 4 weeks) [1]
- First-degree biological relative has documented psychiatric disorder [1]
Alcohol-induced mood disorder [1]:
- Moderate or heavy alcohol use [1]
- Major depression or mania [1]
- Persists for up to 4 weeks after abstinence [1]
- Clears up on stopping alcohol [1]
The differential here asks: is the mood disorder primary (independent) or secondary (alcohol-induced)?
| Diagnosis | Key Distinguishing Features |
|---|---|
| Alcohol-induced depressive disorder | Temporal relationship with heavy alcohol use; symptoms clear within 4 weeks of abstinence [1]; no history of depression before alcohol misuse |
| Primary major depressive disorder with comorbid alcoholism | Depression predates alcohol use; persists > 4 weeks after sustained abstinence; FHx of mood disorder; response to treatment is much less likely if comorbid alcoholism is NOT dealt with [2] |
| Alcohol-induced mania [1] | Manic symptoms in context of heavy alcohol use; resolves with abstinence |
| Bipolar I disorder with comorbid alcoholism | 60% of bipolar I patients have alcoholism [1]; manic/hypomanic episodes predate alcohol use or persist in abstinence; ↑ impulsivity during mania drives drinking |
| Hypothyroidism | Fatigue, weight gain, cold intolerance, constipation; check TFT — alcoholics may have thyroid dysfunction |
| Adjustment disorder | Depressive symptoms temporally related to a psychosocial stressor; does not meet full criteria for MDD; develops within 3 months of stressor [2] |
| Organic causes of depression | Cushing syndrome, malignancy, cerebral pathology — clinical assessment and investigations guided by suspicion |
The 4-Week Rule
If mood or anxiety symptoms persist for > 4 weeks after complete alcohol abstinence, the psychiatric disorder is more likely to be primary (independent) rather than alcohol-induced. This is a critical clinical and exam distinction. Alcohol-induced mood disorder should clear within 4 weeks; alcohol-induced anxiety may take up to 6 months.
Alcohol-induced anxiety disorder [1]:
- Symptoms occur while patient is on heavy alcohol consumption [1]
- Symptoms subside gradually on abstinence, but may persist up to 6 months [1]
- Generalised anxiety disorders / Panic disorder / Phobic anxiety disorders / Social phobia / Obsessive compulsive disorder / PTSD can all be mimicked [1]
- Must be distinguished from alcohol withdrawal syndrome [1]
| Diagnosis | Key Distinguishing Features |
|---|---|
| Alcohol withdrawal | Onset within 6–48h of last drink; autonomic hyperactivity (tremor, sweating, tachycardia); time-limited; responds to BZDs |
| Alcohol-induced anxiety disorder | Occurs during heavy consumption (not just on withdrawal); subside gradually with abstinence but may persist up to 6 months [1] |
| Primary anxiety disorder with self-medication | Anxiety predates alcohol use; persists in extended abstinence (> 6 months); FHx of anxiety; alcohol use may serve as self-medication in pre-existent anxiety disorders [2] |
| Medical causes of anxiety | Thyrotoxicosis, phaeochromocytoma (episodic), hypoglycaemia (episodic), PE, COPD, cardiac arrhythmia [2] |
| Medication/substance-induced anxiety | Stimulants (caffeine, amphetamines, cocaine); withdrawal from other sedatives (BZDs, opioids); medications (corticosteroids, sympathomimetics, anticholinergics) [2] |
| Diagnosis | Key Distinguishing Features |
|---|---|
| Korsakoff syndrome | Profound anterograde amnesia + confabulation; follows untreated Wernicke encephalopathy; mamillary body/medial thalamic damage; other cognitive functions relatively preserved |
| Alcoholic dementia | Frontal-predominant cognitive decline (executive dysfunction, personality change); multifactorial aetiology; diagnosed ≥ 8 weeks after abstinence [2]; cortical atrophy with enlarged ventricles on imaging |
| Alzheimer disease | Insidious onset; progressive; hippocampal atrophy on MRI; amyloid/tau biomarkers; no clear relationship to alcohol intake |
| Vascular dementia | Stepwise deterioration; vascular risk factors; white matter changes on MRI |
| Hepatic encephalopathy | Fluctuating; asterixis; ↑ ammonia; improves with lactulose/rifaximin |
| B12/folate deficiency | Megaloblastic anaemia (but can have neurological features without anaemia); subacute combined degeneration of cord; common in alcoholics due to malabsorption |
| Normal-pressure hydrocephalus | Classic triad: gait apraxia, urinary incontinence, dementia; ventriculomegaly out of proportion to sulcal widening |
| Chronic subdural haematoma | Fluctuating consciousness, headache, focal signs; common in alcoholics (falls + coagulopathy) |
| Diagnosis | Key Distinguishing Features |
|---|---|
| Alcohol withdrawal seizures | Generalised tonic-clonic; onset 12–48h after last drink; often a single seizure or brief cluster; risk of kindling with repeated withdrawals |
| Primary epilepsy | History of seizures unrelated to alcohol use; abnormal EEG; may require long-term AEDs |
| Hypoglycaemia-induced seizures | Low H'stix; responds to glucose |
| Hyponatraemia | Serum Na⁺ < 120 mmol/L; check electrolytes urgently |
| Structural lesion | Subdural haematoma, brain tumour, AVM; focal features on examination; CT/MRI needed |
| Meningitis/encephalitis | Fever, neck stiffness; LP findings |
| Hepatic encephalopathy | Advanced liver disease; ↑ ammonia |
The relationship between alcoholism and psychiatric symptoms is bidirectional, with confounding factors [1]:
This means that when you encounter a patient with both alcohol misuse and psychiatric symptoms, you must consider three possibilities [1]:
- Alcohol → Psychiatric disorder (alcohol-induced): alcohol directly causes the psychiatric symptoms through neurotoxicity, neurotransmitter disruption, or nutritional deficiency
- Psychiatric disorder → Alcohol (self-medication): the patient drinks to cope with pre-existing psychiatric symptoms (e.g. social phobia → drinking to cope with social situations)
- Confounding factors: both the alcohol misuse and the psychiatric disorder are independently caused by shared risk factors (e.g. childhood trauma, genetics, social deprivation) [1]
The key clinical approach to untangling this [1]:
- Evidence of psychiatric disorder BEFORE onset of alcohol abuse or dependence [1]
- Persistent psychiatric symptoms during extended alcohol-free periods (over 4 weeks) [1]
- First-degree biological relative has documented psychiatric disorder [1]
If these criteria are met, the psychiatric disorder is more likely primary (comorbid) rather than alcohol-induced.
Psychiatric comorbidity is very common in alcoholism (lifetime diagnosis occurs in 55% of alcoholics) [2]:
| Comorbid Condition | Prevalence | Key Differentiating Point |
|---|---|---|
| Mood disorders | 40% of alcoholics [2] | Depression is the most common comorbidity; 4× risk of MDD |
| Antisocial personality disorder | 80% of ASPD patients have alcoholism [1] | Longstanding pattern of disregard for others' rights; onset before age 15 |
| Bipolar I disorder | 60% of bipolar I patients [1] | Manic episodes predate alcohol use; impulsivity drives drinking |
| Schizophrenia | 30% abuse alcohol [1] | Alcohol decreases feeling of isolation; temporarily reduces anxiety/depression/insomnia; but increases psychotic symptoms and mood swings [1] |
| Drug addiction | 20% of drug abusers are alcoholic; alcoholics are 6× more prone to become drug abusers [1] | Urine drug screen; polysubstance use history |
| Anxiety disorders | Social phobia, panic disorder common [1] | May be self-medication; must distinguish from withdrawal |
High Yield Summary
Differential Diagnosis of Alcohol-related Disorders — Key Exam Points:
- 6 causes of confusion in alcoholism (must memorise): Intoxication, DT, Head injury/subdural, Metabolic disturbances (hypoglycaemia), Hepatic encephalopathy, Wernicke encephalopathy
- Alcoholic hallucinosis vs DT: Hallucinosis = auditory hallucinations + clear sensorium; DT = visual hallucinations + clouded sensorium + autonomic storm
- Alcohol-induced vs primary psychiatric disorder: Use the 3 criteria — (i) psychiatric disorder before alcohol onset, (ii) persistent symptoms > 4 weeks of abstinence, (iii) FHx of psychiatric disorder
- Alcohol-induced mood disorder clears within 4 weeks of abstinence; alcohol-induced anxiety may persist up to 6 months
- The relationship is bidirectional with confounding factors — alcohol can cause, result from, or co-occur with psychiatric disorders
- Othello syndrome (morbid jealousy): a specific alcohol-related delusional disorder — beware risk of violence (56% of men)
- Always check: H'stix, BAC, NH₃, CT head, electrolytes, and timeline from last drink in any confused alcoholic
Active Recall - Differential Diagnosis of Alcohol-related Disorders
References
[1] Lecture slides: GC 161. Alcohol and the Brain From Psychiatric to Neuropsychiatric Perspectives.pdf (p2, p7, p38, p40–p46, p48) [2] Senior notes: ryanho-psych.md (sections 5.1, 5.1.2; pages 96–110, 142–143, 155, 165)
Diagnostic Criteria, Algorithm, and Investigations for Alcohol Misuse and Alcohol-related Disorders
A. Diagnostic Criteria
The diagnosis of alcohol-related disorders requires understanding three major classification systems that overlap but are not identical. Think of them as different lenses on the same problem: ICD-10 (used in HK clinical practice), DSM-5 (used in research and increasingly in clinical practice), and the historical Edwards & Gross criteria (which heavily influenced ICD-10 and remain conceptually important).
DSM-5 collapsed the older DSM-IV distinction between "alcohol abuse" and "alcohol dependence" into a single dimensional diagnosis: Alcohol Use Disorder (AUD), graded by severity. The logic: abuse and dependence exist on a continuum, not as discrete entities.
A problematic pattern of alcohol use leading to clinically significant impairment or distress, as manifested by at least two of the following, occurring within a 12-month period: [1]
| # | Criterion | Domain | Pathophysiological / Behavioural Basis |
|---|---|---|---|
| 1 | Alcohol is often taken in larger amounts or over a longer period than was intended [1] | Impaired control | Prefrontal cortex dysfunction → impaired executive decision-making; once drinking begins, mesolimbic DA surge overrides planned limits |
| 2 | There is a persistent desire or unsuccessful efforts to cut down or control alcohol use [1] | Impaired control | Craving driven by sensitised incentive-salience system; despite conscious intent to stop, compulsive circuit dominates |
| 3 | A great deal of time is spent in activities necessary to obtain alcohol, use alcohol, or recover from its effects [1] | Impaired control | As dependence progresses, obtaining and using alcohol becomes the organising principle of the day |
| 4 | Craving, or a strong desire or urge to use alcohol [1] | Impaired control | Conditioned cue-reactivity in amygdala/NAc; environmental triggers provoke DA surges → subjective craving |
| 5 | Recurrent alcohol use resulting in a failure to fulfill major role obligations at work, school, or home [1] | Social impairment | Intoxication, withdrawal, and preoccupation with alcohol directly interfere with functioning |
| 6 | Continued alcohol use despite having persistent or recurrent social or interpersonal problems caused or exacerbated by the effects of alcohol [1] | Social impairment | Impaired insight + compulsive use overrides awareness of social consequences |
| 7 | Important social, occupational, or recreational activities are given up or reduced because of alcohol use [1] | Social impairment | Reward hijacking — natural rewards pale compared to drug-induced DA; progressive narrowing of interests |
| 8 | Recurrent alcohol use in situations in which it is physically hazardous [1] | Risky use | Impaired judgement (frontal lobe) + disinhibition → dangerous behaviour (e.g. drunk driving) |
| 9 | Alcohol use is continued despite knowledge of having a persistent or recurrent physical or psychological problem that is likely to have been caused or exacerbated by alcohol [1] | Risky use | Compulsive circuit overrides rational assessment of harm |
| 10 | Tolerance, as defined by either of the following: [1] | Pharmacological | |
| a. A need for markedly increased amounts of alcohol to achieve intoxication or desired effect [1] | GABA-A receptor downregulation + NMDA receptor upregulation (pharmacodynamic tolerance); CYP2E1 induction (pharmacokinetic/metabolic tolerance) | ||
| b. A markedly diminished effect with continued use of the same amount of alcohol [1] | Same neuroadaptive mechanisms — the brain "fights back" against chronic GABA potentiation | ||
| 11 | Withdrawal, as manifested by either of the following: [1] | Pharmacological | |
| a. The characteristic withdrawal syndrome for alcohol [1] | Unmasked NMDA hyperexcitability + loss of GABA-mediated inhibition | ||
| b. Alcohol (or a closely related substance, such as a benzodiazepine) is taken to relieve or avoid withdrawal symptoms [1] | Negative reinforcement — drinking to abolish the aversive withdrawal state (relief drinking) |
Severity grading:
- Mild: 2–3 criteria
- Moderate: 4–5 criteria
- Severe: 6+ criteria
Specify remission: [2]
- In early remission: none of criteria met for ≥ 3 months but < 12 months
- In sustained remission: none met for ≥ 12 months
- In a controlled environment: where access to alcohol is restricted
DSM-5 vs DSM-IV — Key Change
DSM-IV had two separate diagnoses: "Alcohol Abuse" (1 of 4 criteria) and "Alcohol Dependence" (3 of 7 criteria). DSM-5 merged them into one "Alcohol Use Disorder" with 11 criteria (need ≥ 2). The old "legal problems" criterion was dropped and "craving" was added. The logic: the abuse/dependence dichotomy was artificial — in practice, patients existed on a spectrum, and many who had "abuse" were already on the path to dependence.
ICD-10 retains the older two-tier system. This is important because HK clinical practice still uses ICD codes.
ICD-10 Harmful Use (F10.1): [2]
- A pattern of substance use that is causing actual damage to physical or mental health
- The damage may be physical (e.g. hepatitis) or mental (e.g. depression)
- NOT diagnosed if: (1) acute intoxication or "hangover" alone; (2) dependence syndrome, psychotic disorder, or another specific alcohol-related disorder is present
- Why this exclusion? Because harmful use is meant to capture the "intermediate" stage — if the patient already meets criteria for dependence, you code that instead (it's more severe and more specific)
ICD-10 Dependence Syndrome (F10.2): [2]
- ≥ 3 of 6 criteria present together at some time during the previous year:
| Criterion | Explanation |
|---|---|
| (a) Strong desire or sense of compulsion to take the substance | Craving — the subjective experience of incentive-salience |
| (b) Difficulties in controlling substance-taking behaviour (onset, termination, levels of use) | Loss of executive control over drinking |
| (c) Physiological withdrawal state when ceased/reduced, OR use of same/related substance to relieve/avoid withdrawal | The GABA-glutamate imbalance made manifest |
| (d) Evidence of tolerance | Neuroadaptation — need more for same effect |
| (e) Progressive neglect of alternative pleasures or interests + increased time to obtain/use/recover | Reward hijacking |
| (f) Persisting with use despite clear evidence of overtly harmful consequences | Impaired insight + compulsive loop |
These are historically influential — they directly informed the ICD-10 dependence criteria. Think of them as the clinical description that preceded the formal criteria.
Edwards and Gross — Alcohol Dependence Syndrome: [2]
| Element | Description | Clinical Significance |
|---|---|---|
| 1. Narrowing of repertoire | Drinking becomes increasingly stereotyped — same type, same time, same place | The dependent person's drinking pattern is rigid and predictable, unlike the flexible pattern of a social drinker |
| 2. Increased salience of drinking | Maintaining the drinking pattern is given priority over other aspects of life (home, career, recreation) | Functionally equivalent to DSM-5 criterion #7 (giving up activities) |
| 3. Increased tolerance | Increased quantities needed; can tolerate BAC levels that would incapacitate non-tolerant drinkers. Note: tolerance can decrease in later stages of heavy drinking | Early: neuroadaptive tolerance (GABA-A down, CYP2E1 up). Late: hepatic decompensation reduces metabolic capacity → apparent loss of tolerance |
| 4. Withdrawal symptoms | Fall in BAC → tremor, nausea, vomiting, sweating, anxiety, depression, agitation. Heavier dependence → early morning withdrawal after a night's sleep | Why early morning? Because overnight abstinence (8+ hours) allows BAC to drop below the "set point" that the adapted brain now requires |
| 5. Relief drinking | Drinking to relieve or avoid withdrawal symptoms (e.g. "eye-opener" — first drink of the day to stop morning tremor) | Classic negative reinforcement; a very reliable indicator of physiological dependence |
| 6. Subjective awareness of compulsion | The patient recognises a compulsive drive to drink and may resist but ultimately gives in | Distinguishes dependence from simple heavy drinking — the element of loss of control |
| 7. Reinstatement after abstinence | After a period of abstinence, relapse rapidly returns the patient to previous pattern of dependent drinking | The neuroadaptive changes do not fully reverse — "memory" of dependence persists in the reward circuitry |
Alcohol Intoxication DSM-5: [1]
| Criterion | Detail |
|---|---|
| A | Recent ingestion of alcohol [1] |
| B | Clinically significant problematic behavioural or psychological changes (e.g. inappropriate sexual or aggressive behaviour, mood lability, impaired judgement) that developed during, or shortly after, alcohol ingestion [1] |
| C | One or more of the following signs or symptoms developing during, or shortly after, alcohol use: [1] |
| 1. Slurred speech — cerebellar and cortical motor depression | |
| 2. Incoordination — cerebellar Purkinje cell depression | |
| 3. Unsteady gait — cerebellar vermis + proprioceptive pathway depression | |
| 4. Nystagmus — vestibular nucleus and cerebellar flocculus depression | |
| 5. Impairment in attention or memory — NMDA blockade in hippocampus and prefrontal cortex | |
| 6. Stupor or coma — severe generalised CNS depression including brainstem | |
| D | The signs or symptoms are not attributable to another medical condition and are not better explained by another mental disorder, including intoxication with another substance [1] |
DSM-5 criteria for Alcohol Withdrawal:
- A. Cessation of (or reduction in) alcohol use that has been heavy and prolonged
- B. ≥ 2 of the following developing within hours to days after criterion A: (1) autonomic hyperactivity (sweating, tachycardia > 100 bpm); (2) increased hand tremor; (3) insomnia; (4) nausea or vomiting; (5) transient visual, tactile, or auditory hallucinations/illusions; (6) psychomotor agitation; (7) anxiety; (8) generalised tonic-clonic seizures
- C. Symptoms cause clinically significant distress or impairment
- D. Not attributable to another medical condition or mental disorder
- Specify if: with perceptual disturbances (hallucinations with intact reality testing)
The following algorithm walks through the clinical approach to a patient with suspected alcohol-related problems, from initial suspicion through screening, comprehensive assessment, and definitive diagnosis.
C. Screening Tools — In Detail
The name is a mnemonic — each letter stands for one question:
| Letter | Question | What It Detects |
|---|---|---|
| C | Have you ever felt you should Cut down on your drinking? | Awareness of excessive use |
| A | Have people Annoyed you by criticising your drinking? | Social impact |
| G | Have you ever felt Guilty about your drinking? | Emotional consequence |
| E | Have you ever had a drink first thing in the morning (Eye-opener) to steady your nerves or get rid of a hangover? | Relief drinking — highly suggestive of physiological dependence |
- Scoring: ≥ 2 "yes" answers = screen positive
- ↑ Sensitivity but modest specificity only [2] — many false positives
- Strength: very quick (4 questions, takes 30 seconds)
- Weakness: does not quantify consumption; does not detect hazardous drinking below the dependence threshold; poor specificity in populations with high baseline drinking rates
↑ Sensitivity + ↑ Specificity, probably most useful. 10-item screening tool by WHO [2]
The AUDIT is the gold-standard screening tool. It covers three domains in 10 questions:
| Domain | Questions | What It Measures |
|---|---|---|
| Consumption (Questions 1–3) | Frequency of drinking, typical quantity, frequency of heavy drinking | Quantifies actual intake — detects hazardous drinking even without dependence |
| Dependence (Questions 4–6) | Impaired control, failure to meet expectations, morning drinking | Screens for core dependence features |
| Alcohol-related harm (Questions 7–10) | Guilt, blackouts, injury, concern from others | Detects consequences of drinking |
- Scoring: 0–40; ≥ 8 = hazardous drinking (screen positive)
- Cut-offs for clinical action: 8–15 (brief intervention), 16–19 (extended intervention), ≥ 20 (further diagnostic evaluation for dependence)
- Why AUDIT is superior to CAGE: it quantifies consumption (not just consequences), it has better specificity, it detects the full spectrum from hazardous use through to dependence
AUDIT vs CAGE — Exam Comparison
CAGE: 4 items, very quick, good sensitivity but modest specificity; detects dependence features but misses hazardous drinking. AUDIT: 10 items, takes 2–3 minutes, high sensitivity AND specificity; detects the full spectrum from hazardous use to dependence. For screening in clinical settings, AUDIT is preferred.
| Scale | Full Name | Purpose | Scoring |
|---|---|---|---|
| SADQ | Severity of Alcohol Dependence Questionnaire [2] | Estimates severity of dependence; predicts risk during detoxification | > 30 is an indication for inpatient detoxification [2] |
| CIWA-Ar | Clinical Institute Withdrawal Assessment Scale for Alcohol, revised [2] | Quantifies severity of withdrawal (out of 67) [2] | < 10 = very mild; 10–15 = mild; 16–20 = moderate; > 20 = severe [2] |
CIWA-Ar assesses 10 domains: nausea/vomiting, tremor, paroxysmal sweats, anxiety, agitation, tactile disturbances, auditory disturbances, visual disturbances, headache/fullness, and orientation/clouding of sensorium. It is used to guide symptom-triggered benzodiazepine therapy (start at CIWA-Ar ≥ 8) [2].
Why symptom-triggered is preferred: it allows titration to the individual patient's actual withdrawal severity, avoids over-sedation in mild withdrawal, and has been shown to reduce total BZD dose and duration of treatment compared to fixed-dose schedules. However, it requires intensive monitoring (e.g. hourly assessments) [2].
A structured drinking history is the single most important diagnostic tool. It provides information that no blood test or screening questionnaire can:
| Component | What to Ask | Why It Matters |
|---|---|---|
| Initiation [2] | Reason for drinking, triggers, when did daily drinking start | Identifies the trajectory and potential psychological drivers |
| Use [2] | Current, regular, maximal use; describe a typical day (especially note time of first drink) [2] | Early morning drinking = relief drinking = strong indicator of dependence. A typical day reveals the pattern and total daily intake |
| Signs/symptoms of dependence [2] | Compulsion/craving, difficulty in control, stereotyped behaviour, tolerance, withdrawal, persistent despite negative consequences, neglect of other activities | Directly maps to ICD-10/DSM-5 diagnostic criteria |
| Impact [2] | Physical health, mental health, ADL, family, work, social relationships | Quantifies functional impairment — essential for severity grading and treatment planning |
| Quitting [2] | Dates and reasons of abstinence, dates and reasons of relapses, attitude toward change | Assesses stage of change (precontemplation → contemplation → preparation → action → maintenance); predicts treatment engagement |
E. Investigation Modalities and Key Findings
Investigations serve four purposes in alcohol-related disorders:
- Confirm/quantify alcohol use (biomarkers)
- Assess severity of organ damage (blood tests, imaging)
- Detect and correct acute metabolic derangements (emergency labs)
- Rule out alternative diagnoses (CT, LP, toxicology)
| Investigation | Sensitivity | Key Points | Why This Marker Changes |
|---|---|---|---|
| ↑ GGT (gamma-glutamyl transferase) | 70% [2] | Useful screening tool but non-specific, dose-related [2]. Normalises within 2–6 weeks of abstinence. Also elevated in: hepatobiliary disease, obesity, medications (anticonvulsants, barbiturates), diabetes, pancreatitis | Alcohol induces microsomal enzymes including GGT; also released from damaged hepatocytes |
| ↑ MCV (mean corpuscular volume) | 60% [2] | More commonly in females; strong indicator of excessive drinking once other causes ruled out; takes weeks to return to baseline after abstinence [2] | Direct toxic effect of ethanol on erythroblast membranes (↑ membrane fluidity → ↑ cell size) + folate deficiency → impaired DNA synthesis → megaloblastic change. Takes weeks because MCV reflects average of circulating RBCs (lifespan ~120 days) |
| ↑ CDT (carbohydrate-deficient transferrin) | ~70% | More specific than GGT [2]. Best used for monitoring relapse after treatment. Normalises within 2–4 weeks | Chronic alcohol interferes with hepatic glycosylation of transferrin → ↑ proportion of under-glycosylated (carbohydrate-deficient) isoforms |
| Breath/blood alcohol concentration (BAC) | N/A | Only reflects current drinking [2]. Useful in acute settings. No intoxication despite ↑↑ BAC can denote development of tolerance [2] | Directly measures ethanol; metabolised at ~7–10 g/hour (zero-order kinetics) |
Best combination for screening: GGT + MCV together have higher sensitivity than either alone. CDT is more specific and useful for relapse monitoring.
| Investigation | Key Findings in Alcoholism | Interpretation / Why |
|---|---|---|
| LFTs | AST:ALT ratio > 2:1 (classic); ↑ GGT; ↑ bilirubin; ↓ albumin (if cirrhotic) | AST > ALT because: (1) alcohol depletes hepatic pyridoxal-5′-phosphate (B6 cofactor for ALT more than AST); (2) mitochondrial AST (mAST) is released preferentially from alcohol-damaged mitochondria. The 2:1 ratio is fairly specific for alcoholic liver disease |
| FBC | ↑ MCV (macrocytosis ± megaloblastic anaemia); ↓ platelets (thrombocytopenia); ↓ WBC (leucopenia) | Macrocytosis: direct toxicity + folate deficiency. Thrombocytopenia: direct marrow suppression + hypersplenism (portal hypertension → splenomegaly → sequestration). Leucopenia: direct marrow suppression |
| Coagulation | ↑ PT/INR | Liver synthetic failure → ↓ production of clotting factors (especially II, VII, IX, X) |
| U&E | HypoK⁺, hypoNa⁺, hypoMg²⁺, hypoPO₄³⁻ | HypoK: GI losses (vomiting, diarrhoea) + renal losses (↑ aldosterone from volume depletion). HypoNa: beer potomania (excess free water intake with low solute), SIADH, or dilutional. HypoMg: poor dietary intake + renal wasting + GI losses. HypoPO₄: refeeding shifts, poor intake |
| Glucose | Hypoglycaemia (fasting or 6–36h post-ingestion) | ↑ NADH:NAD⁺ ratio → blocked gluconeogenesis |
| Lipids | Hypertriglyceridaemia | ↑ NADH drives ↑ fatty acid synthesis and ↓ fatty acid oxidation |
| Uric acid | ↑ Urate | Lactate (from ↑ NADH) competes with urate for renal tubular excretion |
| B12 / Folate | ↓ Folate (common), ↓ B12 (less common) | Folate: poor dietary intake + malabsorption + alcohol directly impairs folate metabolism. B12: less commonly affected but can occur with chronic gastritis → ↓ intrinsic factor |
| Thiamine level | ↓ (often not routinely measured; treat empirically) | Poor intake + impaired intestinal absorption + increased utilisation |
- Urine toxicology [2]: essential to rule out co-ingestion of other substances (benzodiazepines, opioids, stimulants, cannabis)
- Why? 20% of drug abusers are alcoholic; alcoholics are 6× more prone to become drug abusers [1] — polypharmacy is common and can complicate withdrawal and management
- Also important to check: paracetamol level (common co-ingestant in deliberate self-harm)
| Modality | When to Order | Key Findings |
|---|---|---|
| CT head (non-contrast) | Acute confusion to rule out subdural haematoma, subarachnoid haemorrhage; new seizures to rule out structural cause [2] | Subdural haematoma (crescent-shaped hyper/hypo/mixed density); cortical atrophy with enlarged ventricles (chronic alcoholism); cerebellar vermis atrophy |
| MRI brain | Suspected Wernicke encephalopathy; cognitive decline workup; suspected Marchiafava-Bignami | Wernicke: T2/FLAIR hyperintensity in mamillary bodies, medial thalami, periaqueductal grey, tectal plate. Alcohol-related dementia: cerebral cortical atrophy with enlarged lateral ventricles; loss of grey matter in cortical and subcortical areas; white matter changes with demyelination on DTI [2]. Cerebellar degeneration: cerebellar cortical atrophy especially affecting anterior vermis [2]. Marchiafava-Bignami: corpus callosum necrosis/demyelination. Central pontine myelinolysis: central pontine T2 hyperintensity [2] |
| Investigation | Indication | Key Findings |
|---|---|---|
| ECG | Baseline; palpitations; pre-treatment (some medications prolong QT) | AF (holiday heart); prolonged QT; signs of cardiomyopathy |
| Liver ultrasound | Suspected chronic liver disease | Steatosis (bright liver), cirrhosis (coarse nodular echogenicity, ↓ liver size), portal hypertension (splenomegaly, ascites) |
| FibroScan (transient elastography) | Staging of liver fibrosis | Non-invasive estimation of liver stiffness; guides need for further hepatological follow-up |
| EEG | Seizures of uncertain aetiology; suspected non-convulsive status | Helps distinguish withdrawal seizures from epilepsy; may show generalised slowing in encephalopathy |
| Nerve conduction studies | Suspected peripheral neuropathy | Axonal sensorimotor polyneuropathy (reduced amplitudes, relatively preserved conduction velocities) |
| Ammonia level | Suspected hepatic encephalopathy | ↑ ammonia (though levels correlate poorly with clinical severity) |
| LP | Suspected meningitis/encephalitis | To rule out CNS infection in a febrile, confused alcoholic patient (immunocompromised state) |
Minimum workup in any acutely presenting patient:
| Category | Tests |
|---|---|
| Bedside | H'stix (glucose), vital signs (BP, HR, temp, O₂ sat), BAC (breathalyser), CIWA-Ar scoring |
| Bloods | FBC (MCV, platelets), LFT (AST, ALT, GGT, ALP, bilirubin, albumin), RFT (Na, K, Cr, urea), glucose, Mg²⁺, PO₄³⁻, Ca²⁺, coagulation (PT/INR), B12/folate, thiamine (if available) |
| Urine | Urine toxicology screen [2] |
| Imaging | CT head if: new seizure, focal neurological signs, suspected head injury, altered consciousness not explained by intoxication/withdrawal |
| Other | ECG, ammonia (if liver disease suspected), blood cultures (if febrile), CXR (aspiration pneumonia) |
The AST:ALT > 2:1 Rule
In most liver diseases, ALT > AST. In alcoholic liver disease, the pattern reverses: AST:ALT > 2:1. Why? Alcohol depletes pyridoxal-5′-phosphate (vitamin B6), which is required more for ALT synthesis than AST. Additionally, mitochondrial AST (mAST) is released from alcohol-damaged hepatocyte mitochondria. This ratio is a useful clinical clue but not pathognomonic — it can also be seen in cirrhosis of any cause and in Wilson disease.
F. Diagnostic Criteria for Specific Alcohol-Induced Psychiatric Disorders
These are important because the lecture specifically highlights alcohol-related psychiatric disorders — alcohol-induced psychiatric disorders and comorbid conditions [1].
- Symptoms occur while patient is on heavy alcohol consumption [1]
- Symptoms subside gradually on abstinence, but may persist up to 6 months [1]
- Generalised anxiety disorders / Panic disorder / Phobic anxiety disorders / Social phobia / Obsessive compulsive disorder / PTSD [1]
- Must be distinguished from alcohol withdrawal syndrome [1]
A comorbid primary psychiatric disorder (rather than alcohol-induced) is supported by: [1]
- Evidence of psychiatric disorders before onset of alcohol abuse or dependence [1]
- Evidence of persistent psychiatric symptoms during extended alcohol-free periods (over 4 weeks) [1]
- First-degree biological relative has documented psychiatric disorder [1]
High Yield Summary
Diagnostic Criteria and Investigations — Key Exam Points:
- DSM-5 AUD: ≥ 2 of 11 criteria in 12 months. Mild (2–3), Moderate (4–5), Severe (6+). Single unified diagnosis replacing the old abuse/dependence dichotomy.
- ICD-10 Dependence: ≥ 3 of 6 criteria (compulsion, impaired control, withdrawal, tolerance, neglect, persistent use despite harm).
- Edwards & Gross: 7 elements — narrowing of repertoire, increased salience, tolerance, withdrawal, relief drinking, subjective compulsion, reinstatement after abstinence.
- DSM-5 Intoxication: Recent ingestion + behavioural change + ≥ 1 of 6 signs (slurred speech, incoordination, unsteady gait, nystagmus, attention/memory impairment, stupor/coma) + not better explained by another condition.
- Screening: AUDIT is best (10-item WHO tool, ↑ sens + spec, ≥ 8 screen positive). CAGE is quick but modest specificity.
- SADQ > 30 → inpatient detox. CIWA-Ar: < 10 very mild, 10–15 mild, 16–20 moderate, > 20 severe; guides symptom-triggered BZD therapy (start at ≥ 8).
- Lab biomarkers: ↑ GGT (70% sens, non-specific), ↑ MCV (60% sens, weeks to normalise), ↑ CDT (most specific). AST:ALT > 2:1 classic for alcoholic liver disease.
- Alcohol-induced vs comorbid psych disorder: Use 3 criteria — (i) psych disorder before alcohol, (ii) persistent symptoms > 4wk abstinence, (iii) FHx of psych disorder.
- Always get: H'stix, FBC, LFT, RFT, Mg, PO₄, coag, urine tox. CT head if confused/seizure/focal signs.
Active Recall - Diagnostic Criteria, Algorithm and Investigations
References
[1] Lecture slides: GC 161. Alcohol and the Brain From Psychiatric to Neuropsychiatric Perspectives.pdf (p2, p4–5, p7, p19, p38, p42–43) [2] Senior notes: ryanho-psych.md (sections 5.1, 5.1.1, 5.1.2; pages 96–105, 108–110)
Management of Alcohol Misuse and Alcohol-related Disorders
The management of alcohol-related disorders is staged — it depends entirely on where the patient sits at the time of presentation. A patient in acute intoxication needs different management from one in withdrawal, who in turn needs different management from one seeking long-term relapse prevention. The overarching framework is:
- Acute management — intoxication, withdrawal, DT, Wernicke encephalopathy
- Medium-term — detoxification (managed withdrawal)
- Long-term — relapse prevention (pharmacological + psychosocial)
Let's build this systematically.
B. Acute Management
The management is primarily supportive [2]. Why? Because ethanol is metabolised at a fixed rate (~7–10 g/hour, zero-order kinetics) — there is no antidote that speeds this up. Your job is to keep the patient alive and safe while the alcohol clears.
| Step | Action | Rationale |
|---|---|---|
| ABC | Airway protection (recovery position; intubation if GCS ≤ 8 or aspiration risk), breathing, circulation | Severe intoxication → respiratory depression (medullary depression); aspiration pneumonia from vomiting |
| IV fluid hydration [2] | Correct volume depletion and hypotension [2] | Alcohol causes osmotic diuresis + suppression of ADH → dehydration; vomiting further depletes volume |
| H'stix | Check capillary blood glucose | Hypoglycaemia is an important differential in confused patient with prior alcohol intake [2] — mimics intoxication exactly |
| D50 infusion [2] | If hypoglycaemia is present [2] | Corrects energy substrate deficit; prevents brain injury |
| 100 mg parenteral thiamine [2] | Mandatory if present with coma (for prevention of B₁ deficiency) [2] | Chronic alcoholics are universally at risk of thiamine depletion — glucose loading without thiamine can theoretically precipitate or worsen Wernicke encephalopathy |
| Thiamine + dextrose timing [2] | Traditional teaching: thiamine before dextrose. Evidence: weak, likely NOT evidence-based → thiamine can be given together with dextrose [2] | The theoretical basis is that glucose loading in a thiamine-deficient cell diverts remaining thiamine to glycolysis, starving thiamine-dependent TCA cycle enzymes → lactic acidosis. In practice, the urgency of treating hypoglycaemia outweighs this theoretical risk — give both simultaneously |
| BZD or FGA if agitated [2] | Short-acting BZD (e.g. lorazepam) or haloperidol | Agitated/combative intoxicated patients pose risk to themselves and staff; BZDs are preferred because they share the GABA mechanism; FGAs may be needed if psychotic features present but use cautiously (lower seizure threshold) |
| Monitoring | Regular vitals, GCS, H'stix, temperature | Watch for deterioration — could indicate developing subdural, worsening intoxication (continued absorption), or early withdrawal if blood alcohol level begins to fall |
The 3 Things You Must Do for Every Confused Alcoholic
- Check H'stix — hypoglycaemia kills and is trivially treatable
- Give thiamine — Wernicke encephalopathy is preventable but irreversible if missed
- CT head if any doubt — subdural haematoma is common in alcoholics who fall
Never assume "just drunk" until you have excluded these three emergencies.
2. Management of Alcohol Withdrawal [1][2]
Alcohol withdrawal syndrome [1]:
- Occurs 6–24 hours after last drink [1]
- Autonomic hyperactivity — tremulousness, sweating, nausea, vomiting, anxiety, agitation, tachycardia [1]
- Hypertension, hyperreflexia, insomnia, nightmares, sweating, hyperthermia [1]
- Down-regulation of GABA receptor in chronic alcoholics [1]
- Reversal of inhibition of NMDA receptor → glutamate overactivity [1]
- Disappears in 2–7 days [1]
The treatment principle follows directly from the pathophysiology: the brain is in a state of GABA deficiency and NMDA excess. The treatment is to restore GABAergic tone using a cross-tolerant GABA-A agonist (benzodiazepine) while the brain gradually readapts.
- Hx, P/E: alcohol use and its complications [2]
- Ix: CBC, L/RFT, glucose, urine toxicology [2]
- CT brain: useful to rule out alternative diagnosis in seizures [2]
- SADQ: estimates severity of dependence and thus predicts risk in detoxification [2]
- > 30 is an indication for inpatient detoxification [2]
- CIWA-Ar scale: quantifies severity of withdrawal (out of 67) [2]
- Interpretation: < 10 = very mild, 10–15 = mild, 16–20 = moderate, > 20 = severe [2]
Indications for inpatient detoxification include: [2]
| Indication | Rationale |
|---|---|
| Severe dependence, e.g. SADQ > 30 [2] | Higher risk of severe withdrawal including seizures and DT |
| History of severe withdrawal symptoms, e.g. seizures, DT [2] | Kindling effect — each successive withdrawal is more severe; prior DT is the strongest predictor of future DT |
| Very high alcohol consumption (> 30 units/day) [2] | Greater degree of neuroadaptation → more severe rebound excitotoxicity |
| Concomitant BZD misuse (↑↑ withdrawal severity) [2] | Both alcohol and BZDs act on GABA-A; dual withdrawal is synergistic and potentially lethal |
| Significant medical/psychiatric comorbidity [2] | Comorbid illness increases complications; psychiatric comorbidity increases suicide risk during withdrawal |
| Component | Details | Mechanism / Rationale |
|---|---|---|
| Rule out alternative diagnoses [2] | CNS infection, drug overdose, metabolic derangement, liver failure [2] | All can mimic withdrawal; treating withdrawal alone when the real problem is meningitis or subdural is dangerous |
| Supportive care [2] | NPO (if vomiting), correct volume deficits, stabilise haemodynamics [2] | Dehydration from sweating, vomiting, poor intake; electrolyte loss |
| Correct metabolic derangements [2] | Hypoglycaemia, hypoK, hypoMg, hypoPO₄, ketoacidosis [2] | All common in alcoholics and all worsen withdrawal. HypoMg is particularly important — it lowers the seizure threshold AND impairs thiamine utilisation |
| Thiamine + glucose [2] | To prevent Wernicke encephalopathy [2] | Prophylactic thiamine for ALL patients in withdrawal — the cost of a missed Wernicke is devastating |
| Multivitamins with folate [2] | For nutritional supplements [2] | Chronic alcoholics are universally malnourished; folate deficiency → megaloblastic change |
| Benzodiazepines [1][2] | ↓ Agitation and ↓ withdrawal [2] | Cross-tolerance with alcohol at GABA-A receptor — BZDs substitute for the lost GABAergic effect of alcohol, allowing a controlled taper |
Choice of agent:
| Agent | Properties | When to Use |
|---|---|---|
| Chlordiazepoxide (Librium) [2] | Long-acting; smoother withdrawal; less abuse potential | First-line for planned detox [2]; oral dosing; gradual taper over 5–10 days |
| Diazepam (Valium) [2] | Long-acting (T½ ~20–100h including active metabolites); rapid onset | Alternative first-line [2]; good for acute control; metabolised to active metabolites (desmethyldiazepam) → smooth self-tapering effect |
| Oxazepam [2] | Short-acting; NO active metabolites; does NOT undergo hepatic oxidation (only glucuronidation) | Preferred if severe liver disease present [2] — because cirrhotic liver cannot handle phase I metabolism (oxidation) of other BZDs; also safe in elderly |
| Lorazepam | Short-acting; no active metabolites; glucuronidation only | Alternative in liver disease; also available IV for acute DT/seizures |
Dosing approach:
| Strategy | Description | Pros | Cons |
|---|---|---|---|
| Symptom-triggered [2] | CIWA-Ar ≥ 8 triggers BZD dose; reassess at least hourly [2] | Tailored to individual need; ↓ total BZD dose; ↓ duration of treatment; ↓ over-sedation | Requires intensive monitoring (e.g. Q1h) [2] — not feasible in all settings |
| Fixed-schedule | Predetermined doses at set intervals (e.g. chlordiazepoxide 30 mg QID reducing by 5 mg/day) | Does not require hourly monitoring; simpler | Risk of over-sedation in mild withdrawal; risk of under-treatment in severe withdrawal |
| Prophylactic [2] | Oral chlordiazepoxide (Librium); oxazepam if severe liver disease [2] | Prevents progression to severe withdrawal | Indication: ↑ risk of severe withdrawal (e.g. Hx of seizures/DT) but currently admitted for other reasons with minimal withdrawal symptoms [2] |
Why Long-Acting BZDs?
Long-acting BZDs (diazepam, chlordiazepoxide) are preferred because their active metabolites provide a smooth, self-tapering effect — the drug gradually wears off as the brain readapts. Short-acting BZDs (lorazepam, oxazepam) require more frequent dosing but are safer in liver disease because they bypass hepatic oxidation. Think of it like this: long-acting BZDs ride the wave down gently; short-acting ones create multiple small waves that need to be carefully managed.
Delirium tremens is a medical emergency requiring hospitalisation [1]:
- Severe form of alcohol withdrawal [1]
- Occurs in about 24–96 hours of abstention [1]
- Confusion, hallucination, severe agitation, seizure [1]
- Mortality 5% [1]
Management of DT [1]:
| Intervention | Details | Rationale |
|---|---|---|
| Benzodiazepines in decreasing dosage [1] | Lorazepam / diazepam / others [1]. Often requires high doses — IV diazepam 10–20 mg every 5–15 min until calm (no fixed upper limit in DT; titrate to clinical effect) | Restores GABA-A tone; controls agitation, autonomic storm, and prevents seizures |
| Anticonvulsants [1] | Carbamazepine [1] | Adjunct for seizure prevention; acts via sodium channel blockade and may also modulate glutamate. Not a substitute for BZDs in DT but can be useful as adjunct or prophylaxis |
| Proactive use of parenteral vitamins (thiamine) [1] | IV thiamine 500 mg TDS for 3 days (Pabrinex or equivalent) | Prevents Wernicke encephalopathy — DT patients are at extreme risk |
| Neuroleptics for control of agitation [1] | Haloperidol (low dose, e.g. 2–5 mg); avoid in isolation — always give with BZDs | Controls psychotic symptoms (hallucinations, paranoid delusions) and severe agitation. BUT: antipsychotics lower seizure threshold → never use alone without BZD cover |
| Fluid and electrolyte balance [1] | IV fluids (0.9% NaCl or balanced crystalloid); replace K⁺, Mg²⁺, PO₄³⁻ | Profound losses from sweating, fever, agitation; hypoMg lowers seizure threshold |
| Barbiturates or propofol [2] | For refractory DT [2] — when BZDs fail to control symptoms despite high doses | Barbiturates (phenobarbital) act at a different site on GABA-A (prolong channel opening vs BZD which increase frequency); propofol for ICU-level sedation |
Refractory DT — What Counts as Failure?
If a patient requires > 50 mg diazepam in the first hour or continues to have severe agitation/autonomic instability despite adequate BZD dosing, consider refractory DT. Escalate to phenobarbital (200 mg IV boluses) or propofol infusion (requires intubation and ICU). These cases have a mortality approaching 15% and need ICU management.
- Most alcohol withdrawal seizures are self-limiting (< 5 minutes, generalised tonic-clonic)
- Immediate treatment: IV lorazepam 4 mg (or IV diazepam 10 mg)
- Status epilepticus: BZDs, phenobarbital, propofol [2]
- Long-term anticonvulsants are generally NOT indicated for isolated withdrawal seizures — the seizures are provoked by withdrawal, not by an underlying epileptic disorder
- Always CT head to rule out structural cause (subdural, SAH) — especially if focal features, first seizure, or atypical presentation
Wernicke's encephalopathy [1]:
- Medical emergency [1]
- 20% mortality [1]
- Only 20% detected in life [1] — highlighting the need for high clinical suspicion and low threshold for treatment
- IM/IV Thiamine [1]
- Progression to Korsakoff's Psychosis in 84% [1] if untreated
| Treatment | Details | Rationale |
|---|---|---|
| IV thiamine | 500 mg TDS for 3 days, then 250 mg daily for 3–5 days | Thiamine pyrophosphate (TPP) is essential cofactor for pyruvate dehydrogenase, α-ketoglutarate dehydrogenase, and transketolase. High-dose IV ensures adequate CNS penetration (only ~5% of oral thiamine is absorbed; in alcoholics, absorption is even lower due to damaged GI mucosa) |
| Then oral thiamine | 100 mg TDS ongoing | Maintenance supplementation after acute phase |
| Why NOT oral alone? | Oral bioavailability of thiamine is extremely poor in alcoholics | Chronic alcohol damages jejunal mucosa (where thiamine is actively absorbed via THTR-1 transporter) AND alcohol directly inhibits thiamine transporter expression |
Approach to management of alcohol misuse (NICE 2014): [2]
| Severity | Management |
|---|---|
| At-risk / hazardous drinking (non-dependent) | Brief intervention [2] — simple education and advice about safe levels of alcohol consumption |
| Mild dependence [2] | Offer a high-intensity psychotherapy [2] |
| Moderate / severe dependence [2] | Offer acamprosate / PO naltrexone in combination with a high-intensity psychological treatment [2] |
| ↑ Intake (> 15 units/day) and/or ≥ 15–30 on SADQ [2] | Offer acute treatment vs withdrawal in community or inpatient settings (depending on safety) [2] |
Goal of treatment [2]:
- Controlled drinking for those detected early, non-dependent with minimal health sequelae [2]
- Total abstinence for those who were dependent, with failed prior attempts at controlled drinking [2]
D. Long-term Pharmacological Treatment — Relapse Prevention
These medications are used after detoxification to help maintain abstinence or reduce heavy drinking. They work through different mechanisms and have different indications.
| Property | Detail |
|---|---|
| Drug class | NMDA receptor modulator / glutamate antagonist |
| Name breakdown | "a-camprosate" — derived from calcium acetyl-homotaurinate; structurally similar to GABA and glutamate |
| Mechanism of action | Restores the balance between glutamatergic excitation and GABAergic inhibition that is disrupted by chronic alcohol use. Specifically: (1) antagonises mGluR5 receptors → ↓ glutamatergic hyperexcitability; (2) may weakly potentiate GABA-A. Reduces the "hyperexcitable" brain state that drives craving and relapse |
| Indication | Moderate/severe dependence, in combination with high-intensity psychological treatment [2]. First-line for relapse prevention (NICE) |
| Contraindications | Severe renal impairment (renally excreted — not hepatically metabolised, so actually safe in liver disease); pregnancy/breastfeeding |
| Timing | Start as soon as abstinence is achieved (during or immediately after detox); continue for 6–12 months |
| Key advantage | Safe in liver disease (unlike disulfiram, which requires hepatic metabolism and monitoring) |
| Efficacy | NNT ~12 to prevent one return to any drinking over 3–12 months |
Why Acamprosate Works — From First Principles
Remember: chronic alcohol causes NMDA receptor upregulation. After alcohol is removed, these upregulated NMDA receptors are no longer suppressed → excessive glutamatergic excitation → this is what drives the persistent dysphoria, anxiety, craving, and "protracted withdrawal" that makes relapse so common in the weeks-months after detox. Acamprosate dampens this glutamatergic hyperexcitability, essentially easing the brain's transition back to a non-alcohol-adapted state.
| Property | Detail |
|---|---|
| Drug class | Opioid receptor antagonist |
| Name breakdown | "nal-" = nalorphine derivative (opioid antagonist prefix); "-trexone" = long-acting modification |
| Mechanism of action | Blocks µ-opioid receptors in the mesolimbic reward pathway. Alcohol normally stimulates endogenous opioid (β-endorphin) release → DA release in NAc → pleasurable reinforcement. Naltrexone blocks this pathway → ↓ reinforcing "buzz" from drinking → ↓ craving → if the patient does drink, the rewarding effect is blunted |
| Indication | Moderate/severe dependence, in combination with high-intensity psychological treatment [2]. Can be used even if the patient is still drinking (harm reduction approach) |
| Contraindications | Concurrent opioid use (will precipitate acute opioid withdrawal); severe hepatic impairment (hepatotoxicity risk at high doses); acute hepatitis |
| Side effects | Nausea (commonest), headache, dizziness, fatigue, hepatotoxicity at high doses |
| Dosing | 50 mg PO daily; injectable extended-release (380 mg IM monthly — Vivitrol) available in some settings |
| Key advantage | Reduces heavy drinking days even if full abstinence is not achieved → useful for harm reduction |
| Property | Detail |
|---|---|
| Drug class | Aldehyde dehydrogenase (ALDH) inhibitor |
| Name breakdown | "di-sulfiram" = contains two sulfur groups; originally discovered as a rubber vulcanisation agent whose workers developed unpleasant reactions to alcohol |
| Mechanism of action | Irreversibly inhibits ALDH → if patient drinks alcohol, acetaldehyde accumulates → extremely unpleasant "disulfiram-ethanol reaction" (DER): flushing, nausea, vomiting, headache, tachycardia, hypotension, chest pain. This creates a powerful negative reinforcement — the patient learns to associate drinking with severe aversive consequences |
| Indication | Patients who are highly motivated and want a "safety net" to reinforce abstinence; supervised consumption (e.g. by spouse, nurse, or pharmacy) is most effective |
| Contraindications | Cardiac disease (DER can cause arrhythmia, MI); severe hepatic impairment; pregnancy; psychosis (can worsen); patients who are unreliable or impulsive (risk of deliberate drinking on disulfiram → medical emergency) |
| Side effects | Without alcohol: drowsiness, fatigue, garlic-like taste. With alcohol: the DER (see above) — can be life-threatening in severe cases (cardiovascular collapse) |
| Key advantage | Very effective when supervised; particularly useful in patients who have achieved abstinence and want to prevent impulsive relapse |
| Key disadvantage | Requires absolute motivation and compliance; unsupervised use has poor outcomes; hepatotoxicity requires LFT monitoring |
Disulfiram = Pharmacological ALDH2*2
Disulfiram pharmacologically mimics what the ALDH2*2 mutation does genetically in East Asians. Both cause acetaldehyde accumulation → aversive reaction → deterrence from drinking. The principle is identical — aversion therapy through biochemical consequences.
| Property | Detail |
|---|---|
| Drug class | Opioid receptor antagonist (partial agonist at κ-receptors) |
| Name breakdown | "nal-" = opioid antagonist prefix; "-mefene" = methylenated derivative |
| Mechanism of action | Similar to naltrexone (µ-opioid antagonist) but with additional partial agonism at κ-opioid receptors → may provide additional anti-reward effects |
| Indication | Opioid antagonist, superior to placebo in severe dependence only [2]. Licensed for reduction of alcohol consumption (as-needed dosing before anticipated drinking occasions) rather than for maintaining abstinence |
| Contraindications | Concurrent opioid use; severe hepatic/renal impairment |
| Key difference from naltrexone | Taken "as needed" (PRN) rather than daily; specifically for harm reduction in patients not yet ready for abstinence |
- May be useful in those with comorbid depression [2]
- SSRIs are first-line if treating comorbid depression
- NOT effective for alcohol dependence in the absence of comorbid depression
- Important: response to treatment of mood disorder is much less likely if comorbid alcoholism is NOT dealt with [2] — always treat the alcohol problem alongside the depression
| Feature | Acamprosate | Naltrexone | Disulfiram | Nalmefene |
|---|---|---|---|---|
| Mechanism | ↓ Glutamatergic hyperexcitability | Blocks opioid-mediated reward | ALDH inhibition → aversive reaction | µ-opioid antagonist + κ partial agonist |
| Goal | Maintain abstinence | ↓ Heavy drinking / maintain abstinence | Enforce abstinence | ↓ Heavy drinking |
| Timing | Start at abstinence; daily | Daily or IM monthly | Daily (supervised) | PRN before drinking |
| Liver safety | Safe (renally excreted) | Caution (hepatotoxic at high dose) | Caution (hepatotoxic; needs LFT monitoring) | Caution |
| Use with opioids? | Yes | NO (precipitates withdrawal) | Yes | NO |
| NICE first-line? | Yes (with naltrexone) | Yes (with acamprosate) | Second-line | For harm reduction |
E. Psychosocial Treatment [2]
Psychosocial interventions are the backbone of long-term management. Medications improve outcomes, but without addressing the psychological and social drivers of drinking, relapse is nearly inevitable.
- Efficacious for non-dependent, at-risk alcohol use [2]
- Involves: simple education and advice about safe levels of alcohol consumption [2]
- Efficacy: usually modest reduction in alcohol consumption over next few years [2]
- Utility: best for those with at-risk drinking (alcohol use above limit but non-dependent) [2]
- Typical format: 5–15 minute structured conversation (FRAMES: Feedback, Responsibility, Advice, Menu of options, Empathy, Self-efficacy)
- Basis: transtheoretical model of behaviour change — asserts that there are different levels of readiness to change among individuals [2]
- Stages: precontemplation → contemplation → preparation → action → maintenance → (relapse is part of the cycle)
- MI assesses readiness for change followed by attempts to build internal motivation to change based on patient's stage [2]
- Principles: express empathy, develop discrepancy, roll with resistance, support self-efficacy [2]
- Techniques [2]:
- Engage patient thoughtfully by reflective listening
- Focusing on a specific issue to be changed
- Evoking patient's own thoughts that motivate them towards change
- Planning, at least in the conceptual aspect, for changes
- Efficacy: effective at short- and long-term across all substances [2]
- Utility: allows patient to generate own arguments and motivation for change; facilitates change especially when patient is ambivalent [2]
MI — The 'Spirit' of the Approach
MI is NOT about telling the patient what to do. It is about helping the patient discover their own reasons for change. The core insight is that humans resist being told what to do (reactance), but are more likely to change when they articulate their own reasons. The clinician's role is to create the conditions where this self-discovery can happen — through empathic, non-judgemental, curious questioning.
- Structured goal-directed form of psychotherapy [2]
- Involves [2]:
- Psychoeducation to let patient understand how their thought processes contribute to their behaviour
- Behavioural treatment to help patients develop new and adaptive ways of behaving and alter their social environment → in turn leads to change in thoughts and emotions
- Efficacy: modest positive effects on substance use [2]
- Specific CBT techniques for alcohol include: identifying high-risk situations, developing coping strategies, cognitive restructuring of pro-drinking beliefs, relapse prevention training
- Alcoholics Anonymous (AA) [2]: 12-step programme; peer support; emphasis on powerlessness over alcohol, spiritual growth, and lifelong commitment to abstinence
- Efficacy: strong evidence for AA/12-step facilitation; comparable to CBT in maintaining abstinence
- Not suitable for all (some patients find the spiritual emphasis off-putting; alternatives include SMART Recovery)
- Cue exposure therapy: to ↓ effect of drinking cues and to prevent relapse [2] — based on classical conditioning principles; repeated exposure to alcohol-related cues without drinking leads to extinction of the conditioned craving response
- Contingency management: offer incentives to encourage abstinence or discourage substance use [2] — operant conditioning; positive reinforcement for drug-free urine samples or attendance at sessions
| Condition | Management | Key Points |
|---|---|---|
| Alcohol-induced mood disorder [1] | Abstinence — clears up on stopping alcohol; persists for up to 4 weeks after abstinence [1] | If depression persists > 4 weeks after abstinence → consider primary mood disorder → treat with antidepressant |
| Alcohol-induced anxiety disorder [1] | Abstinence — symptoms subside gradually but may persist up to 6 months [1] | Must be distinguished from alcohol withdrawal syndrome [1]; if persists > 6 months → primary anxiety disorder |
| Alcoholic hallucinosis [1] | Treatment with antipsychotics and advice to abstain from alcohol [1] | Some develop schizophrenia, some remit after stopping alcohol use [1] |
| Morbid jealousy (Othello syndrome) [2] | Antipsychotics + abstinence [2] | Beware risk of violence (56% of men) [2]; may need couple safety planning |
| Alcohol-related sleep disorders [2] | Abstinence; sleep hygiene; sleep changes persist for 2 years after abstinence [2] | Avoid using BZDs for sleep in recovering alcoholics (cross-dependence risk) |
When schizophrenia is comorbid with alcoholism (30%) [1]:
- Alcohol decreases feeling of isolation [1]
- Temporarily reduces symptoms of anxiety / depression / insomnia [1]
- BUT increases psychotic symptoms and mood swings [1]
- Disruptive behaviour, suicide, treatment non-compliance, drug abuse, poor clinical outcome [1]
- Drug accumulation due to hepatic damage [1]
- Management: treat both simultaneously; optimise antipsychotic medication; be aware that hepatic damage alters drug metabolism → risk of toxicity at standard doses
Key principle: response to treatment is much less likely if comorbid alcoholism is NOT dealt with in a patient with a mood disorder [2]. Always address alcohol dependence as part of the treatment plan for any comorbid psychiatric condition.
High Yield Summary
Management of Alcohol-related Disorders — Key Exam Points:
- Acute intoxication: Supportive — ABC, IV fluids, H'stix, thiamine (before or with glucose), BZD/FGA if agitated. No antidote.
- Withdrawal: BZDs are cornerstone — prefer long-acting (chlordiazepoxide, diazepam); use oxazepam/lorazepam in liver disease. Symptom-triggered dosing (CIWA-Ar ≥ 8) preferred over fixed-schedule.
- DT: Medical emergency (5% mortality). IV BZD in decreasing dosage, anticonvulsants (carbamazepine), parenteral thiamine, neuroleptics for agitation, fluid/electrolyte balance. Barbiturates/propofol for refractory cases.
- Wernicke: Medical emergency (20% mortality). IV thiamine 500 mg TDS × 3 days. Only 20% detected in life → low threshold for treatment. 84% progress to Korsakoff if untreated.
- Inpatient detox indications: SADQ > 30, Hx seizures/DT, > 30 units/day, concurrent BZD misuse, significant comorbidity.
- NICE staged approach: At-risk → brief intervention. Mild dependence → psychotherapy. Moderate/severe → acamprosate or naltrexone + psychotherapy.
- Relapse prevention drugs: Acamprosate (↓ glutamate, safe in liver disease), Naltrexone (blocks opioid reward, CI in opioid use), Disulfiram (ALDH inhibitor → aversive reaction, needs supervision), Nalmefene (PRN harm reduction).
- Psychosocial: MI (assess readiness, build motivation), CBT (identify triggers, develop coping), AA (12-step peer support), Brief intervention (at-risk drinkers).
- Treatment goals: Controlled drinking (early, non-dependent) vs Total abstinence (dependent, failed controlled drinking).
- Always treat alcohol alongside comorbid psychiatric disorders — response to psych treatment is much less likely if alcoholism is not addressed.
Active Recall - Management of Alcohol Misuse and Alcohol-related Disorders
References
[1] Lecture slides: GC 161. Alcohol and the Brain From Psychiatric to Neuropsychiatric Perspectives.pdf (p10, p12, p14, p38, p40–41, p44) [2] Senior notes: ryanho-psych.md (sections 5.1, 5.1.1, 5.1.2; pages 96–105, 109–110; section 3.1.4.1 on BZDs; section 3.3.4 on psychotherapy indications)
Complications of Alcohol Misuse and Alcohol-related Disorders
Alcohol is arguably the most damaging substance to the human body when used chronically — it affects virtually every organ system. The complications are best understood through the lens of four overarching mechanisms of damage:
- Direct cytotoxicity — ethanol and its metabolite acetaldehyde are directly toxic to cell membranes, mitochondria, and DNA
- Nutritional deficiency — chronic alcoholics eat poorly, absorb nutrients poorly (damaged GI mucosa), and alcohol directly interferes with vitamin metabolism (especially B1, B3, B6, B12, folate)
- Metabolic disruption — the massive shift in hepatic NAD⁺/NADH ratio disrupts gluconeogenesis, fatty acid oxidation, the TCA cycle, and uric acid excretion
- Immune dysregulation — chronic alcohol suppresses both innate and adaptive immunity → increased susceptibility to infections
Every complication below can be traced back to one or more of these four mechanisms. Let's work through each system.
A. Acute Complications
- Dose-dependent CNS depression (covered in detail in prior sections)
- Alcoholic blackouts: transient amnesia lasting hours, without impairment of conscious level; caused by NMDA receptor inhibition in hippocampus → failure of long-term potentiation (LTP) [2]
- Traumatic brain injury: falls during intoxication are extremely common; alcoholics have impaired balance (cerebellar), poor judgement (prefrontal), and impaired protective reflexes → head injuries → subdural haematoma (further compounded by coagulopathy and thrombocytopenia)
- Occurs after a binge followed by fasting/vomiting → depleted glycogen stores + ↑ NADH:NAD⁺ ratio + ↑ free fatty acid mobilisation → ↑ ketone body production (β-hydroxybutyrate predominates over acetoacetate because of the shifted redox state)
- Presents with: anion-gap metabolic acidosis, abdominal pain, nausea, vomiting, tachypnoea (Kussmaul breathing)
- Glucose may be low, normal, or mildly elevated (unlike diabetic ketoacidosis where glucose is markedly elevated)
- Mx: IV fluids (NS with dextrose), thiamine, electrolyte correction
| Complication | Timeline | Key Features | Mortality |
|---|---|---|---|
| Withdrawal syndrome | 6–24h after last drink | Tremor, sweating, nausea, anxiety, tachycardia, hypertension [1] | Low if treated |
| Withdrawal seizures | 12–48h | Generalised tonic-clonic; risk of kindling [2] | Low if single; status epilepticus can be fatal |
| Delirium tremens [1] | 24–96 hours of abstention [1] | Confusion, hallucination, severe agitation, seizure [1]. Autonomic storm | Mortality 5% [1]; < 5% if treated, up to 35% untreated |
B. Chronic Neurological Complications
Alcoholism affects the brain front (frontal dementia), back (cerebellar vermis) and centre (corpus callosum) [2] — this mnemonic elegantly captures the three major chronic brain lesions.
This is the single most important neurological complication to understand.
Wernicke Encephalopathy (WE) [1][2]:
- Mostly alcoholic / some non-alcoholic [1]
- Thiamine deficiency [1]
- Only 20% detected in life (Harper 1983) [1] — the classic triad is only present in ~10–16% of cases; most are diagnosed post-mortem
- Medical emergency [1]
- 20% mortality [1]
- IM/IV Thiamine [1]
- Progression to Korsakoff's Psychosis in 84% (Victor 1989) [1]
- Clinical triad [2]:
- Encephalopathy: delirium with profound disorientation, apathy, inattention, amnesia [2]
- Oculomotor dysfunction: ophthalmoplegia (combination of bilateral palsies), nystagmus (most commonly horizontal but can be vertical), pupillary abnormalities (sluggish or unequal pupils) [2]
- Truncal ataxia: vermis-type — ataxic, wide-based gait with short steps [2]
- Other features: polyneuropathy (50%), hypothermia (1–4%), vestibular dysfunction, coma (rare) [2]
- Diagnosis [2]: Caine criteria (≥ 2 out of 4): dietary deficiency, oculomotor abnormalities, cerebellar dysfunction, altered mental state or amnesia [2]
- Imaging: T2/FLAIR hyperintensity in mammillary bodies, medial thalami, periaqueductal grey [2]
- Course with treatment: ocular signs improve within hours to days; confusion subsides in days to weeks [2]
- Prognosis: mortality 17% in acute stage; majority have residual deficits (nystagmus, ataxic gait, memory deficits) [2]
Korsakoff Syndrome [2]:
- Develops in 84% of untreated WE patients [1]
- Profound anterograde amnesia (inability to form new memories) with relative preservation of other cognitive functions
- Confabulation — fabricated memories to fill gaps (the brain's attempt to make narrative sense of missing data; not deliberate lying)
- Retrograde amnesia with temporal gradient (more recent memories lost preferentially)
- Pathology: bilateral mammillary body and medial thalamic nuclei damage — these are key nodes in the Papez circuit (hippocampus → fornix → mammillary bodies → mammillothalamic tract → anterior thalamus → cingulate cortex → hippocampus), which is the circuit for memory consolidation
- Largely irreversible — only ~20% show significant recovery even with thiamine supplementation
- Pathogenesis: nutritional deficiency + direct neurotoxicity → degeneration of Purkinje cells in cerebellar cortex → vermis atrophy [2]
- S/S: subacute/chronic onset of ataxic gait followed by other features of truncal ataxia [2]. Heel-shin test is usually abnormal with severe gait disturbances, but finger-nose testing may reveal only mild abnormalities [2] — why? Because the vermis controls midline/truncal coordination (gait, posture), while the lateral cerebellar hemispheres control limb coordination (finger-nose). Alcohol preferentially damages the vermis.
- A midline section of the cerebellum from a non-alcoholic (left) and an alcoholic (right) patient shows atrophy of the folia and widening of the sulci in the anterior superior aspect of the cerebellar vermis in the alcoholic patient [1]
- Course: stabilises with abstinence, but progresses with continued drinking [2]
- Dx: clinical + CT/MRI showing cerebellar cortical atrophy especially affecting anterior vermis [2]
- Mx: cessation of drinking and nutritional supplementation [2]
- Prevalence: ~50–70% of alcohol abusers have some degree of cognitive deficits [2]
- Pathophysiology: usually multifactorial — NOT solely attributed to ethanol use [2]
- S/S: cognitive impairment simulating frontal lobe dementia (the frontal lobes are more susceptible to alcohol damage) [2] — executive dysfunction, personality change, disinhibition, impaired planning
- Alcohol-induced neurological deficit [1]:
- Dx: diagnosed ≥ 8 weeks after abstinence, based on multiple criteria (Oslin 1998, DSM-5) [2]
- Neuroimaging findings [2]:
- Cerebral cortical atrophy with enlarged lateral ventricles
- Loss of grey matter in cortical and subcortical areas
- White matter changes with demyelination on DTI
Alcohol and stroke [1]:
- Haemorrhagic stroke (15% of all strokes): heavy drinking → ↑ risk [1]
- Ischaemic stroke (85%): light/moderate drinking → ↓ risk [1]
- Wine is associated with ↓ risk of stroke, but no such relationship for beer/spirits [2]
Why does heavy drinking increase haemorrhagic stroke risk? Multiple mechanisms: (1) chronic hypertension (alcohol activates the RAAS and sympathetic nervous system); (2) impaired coagulation (hepatic dysfunction → ↓ clotting factors + thrombocytopenia); (3) direct vascular endothelial damage from acetaldehyde.
Why might light/moderate drinking decrease ischaemic stroke risk? (1) ↑ HDL cholesterol; (2) ↓ platelet aggregation; (3) ↓ fibrinogen. However, this is controversial — current WHO guidance (2023) and recent large studies suggest there is no safe level of alcohol for overall health.
- Symmetric distal sensorimotor polyneuropathy — "stocking-glove" distribution
- Painful paraesthesiae, burning feet, ↓ ankle jerks, distal sensory loss
- Mechanism: direct neurotoxicity of ethanol + B-vitamin deficiency (B1, B6, B12) → axonal degeneration ("dying-back" neuropathy — the longest axons are most vulnerable because they depend most on axonal transport, which requires energy/nutrition)
- Affects up to 50% of chronic alcoholics
- Rare demyelinating disorder of corpus callosum [2]
- Pathology: demyelination or necrosis of corpus callosum and adjacent subcortical white matter due to hypo-vitamin B (especially B₁) [2]
- S/S: usually in 40–60 y/o, with subacute onset of [2]:
- Frontal syndrome: frontal dementia, personality changes
- Others: seizures, spasticity, rigidity, paralysis, coma, death
- Neuroimaging: classically hypodense/vacuolation of corpus callosum with white matter lesions [2]
- Prognosis: variable — death, demented state, or recovery possible [2]
- Cause: rapid correction of hyponatraemia in acute intoxication → demyelination of pons [2]
- S/S: spastic paralysis of 4 limbs, pseudobulbar palsy, personality changes, inappropriate affect, delusions; "locked-in" syndrome in severe cases [2]
- Prevention: never correct hyponatraemia quicker than ~10 mmol/24h [2]
- Why the pons? The basis pontis has a unique vascular supply (end-artery territory) and a high density of oligodendrocytes that are vulnerable to osmotic stress. Rapid Na⁺ correction → rapid water efflux from brain cells → oligodendrocyte shrinkage and apoptosis → demyelination
| Complication | Mechanism | Key Features | Management |
|---|---|---|---|
| B12 deficiency [2] | Poor nutrition in chronic alcoholism | Subacute combined degeneration of cord, peripheral neuropathy, ataxia, optic atrophy, dementia, depression, psychosis, delirium. Classically loss of ankle jerk (peripheral neuropathy) with ↑ knee jerk (SCD of cord) [2]. Require ~350 pg/mL for proper neurological function cf 200 pg/mL for haematological function [2] | IM cyanocobalamin 1 mg daily × 7 → 1 mg weekly × 4 → 1 mg monthly [2] |
| B3 deficiency (pellagra) [2] | Poor nutrition | 3Ds: dementia, dermatitis, diarrhoea; peripheral neuropathy; psychiatric changes (irritability, apathy, depression, cognitive impairment) [2] | Nicotinic acid 50 mg TDS PO [2] |
| Alcohol-tobacco amblyopia [2] | Heavy drinking + smoking → deficiency of thiamine or B12 → optic atrophy [2] | ↓ VA with central scotoma and loss of colour vision [2] | Vitamin B12 supplementation [2] |
| Complication | Mechanism | Clinical Significance |
|---|---|---|
| Alcoholic liver disease | Steatosis (↑ NADH → ↓ fatty acid oxidation) → Steatohepatitis (acetaldehyde-protein adducts → immune activation) → Fibrosis → Cirrhosis (stellate cell activation → collagen) → HCC | Progressive spectrum; cirrhosis is irreversible; HCC screening needed |
| Oesophageal varices | Cirrhosis → portal hypertension → portosystemic collateral formation at oesophageal submucosal veins | Risk of catastrophic upper GI bleed; mortality ~20% per episode |
| Mallory-Weiss tear | Forceful vomiting (common in alcoholics) → mucosal tear at gastro-oesophageal junction | Upper GI bleed; usually self-limiting |
| Gastritis / PUD | Direct mucosal irritation by ethanol; ↑ gastric acid secretion; impaired mucosal defences | Epigastric pain, haematemesis |
| Acute pancreatitis | Alcohol is the 2nd commonest cause (after gallstones in HK). Mechanism: premature activation of pancreatic enzymes + direct acinar cell toxicity by ethanol/acetaldehyde | Severe epigastric pain radiating to back; ↑ amylase/lipase |
| Chronic pancreatitis | Repeated inflammation → protein plug formation in ducts → calcification → exocrine/endocrine failure | Chronic pain, steatorrhoea, diabetes mellitus |
| Malabsorption | Damaged intestinal mucosa + pancreatic exocrine failure + biliary dysfunction | Contributes to all nutritional deficiencies |
| GI malignancies | Acetaldehyde is a Group 1 carcinogen (IARC) — directly damages DNA and impairs DNA repair | ↑ Risk of oropharyngeal, laryngeal, oesophageal cancers (synergistic with smoking) |
| Complication | Mechanism | Key Features |
|---|---|---|
| Alcoholic cardiomyopathy | Direct myocardial toxicity from ethanol and acetaldehyde → myocyte apoptosis → dilated cardiomyopathy | Progressive heart failure (dyspnoea, oedema, fatigue); partially reversible with abstinence |
| Atrial fibrillation ("Holiday Heart") | Binge drinking → direct electrophysiological effects on atrial myocytes + autonomic surge (↑ sympathetic, ↓ vagal) → triggered AF | Often self-terminating; recurrent if binge pattern continues |
| Hypertension | Chronic sympathetic activation + RAAS activation + direct vascular effects | Dose-dependent; ↓ with abstinence |
| Ischaemic heart disease | Complex relationship — light/moderate drinking may be protective (↑ HDL, ↓ platelet aggregation) but heavy drinking is harmful (hypertension, cardiomyopathy, arrhythmia) | J-shaped curve; controversial |
| Complication | Mechanism | Key Features |
|---|---|---|
| Macrocytosis without anaemia | Direct toxic effect on erythroblast membranes (↑ membrane fluidity → ↑ cell size) + folate deficiency | ↑ MCV is often the first clue to occult heavy drinking |
| Megaloblastic anaemia | Folate deficiency → impaired DNA synthesis | Macro-ovalocytes, hypersegmented neutrophils |
| Sideroblastic anaemia | Alcohol inhibits δ-aminolaevulinic acid synthase (the first enzyme in haem synthesis) | Ring sideroblasts on bone marrow |
| Thrombocytopenia | Direct marrow suppression + hypersplenism (portal hypertension → splenomegaly → sequestration) | ↑ Bleeding risk; typically corrects with abstinence |
| Compromised immunity | Alcohol impairs neutrophil chemotaxis, phagocytosis, T-cell function, and cytokine production | ↑ Risk of pneumonia, TB, spontaneous bacterial peritonitis |
| Zieve syndrome | Rare triad: haemolytic anaemia + jaundice + hyperlipidaemia in the setting of alcoholic liver disease | Haemolysis due to altered RBC membrane lipids |
| Complication | Mechanism |
|---|---|
| Hypoglycaemia | ↑ NADH:NAD⁺ ratio → blocked gluconeogenesis [2] |
| Pseudo-Cushing syndrome | Chronic alcohol → ↑ CRH and ACTH → ↑ cortisol. Features mimic Cushing's but resolve with abstinence |
| Electrolyte disturbance | HypoK⁺ (GI losses + renal wasting), hypoNa⁺ (beer potomania, SIADH), hypoMg²⁺ (poor intake + renal wasting), hypoPO₄³⁻ (refeeding shifts, poor intake) [2] |
| Hypogonadism | ↑ Aromatisation of androgens → oestrogens in cirrhotic liver + direct gonadal toxicity → gynaecomastia, testicular atrophy, impotence, infertility [2] |
| Alcoholic ketoacidosis | Binge → fasting → ↑ NADH + ↑ free fatty acids → ↑ ketone bodies |
Fetal Alcohol Syndrome (FAS) [1]:
- Heavy drinking → 30% risk [1]
- 1–4 per 1000 live births in the US [1]
- Microcephaly [1]
- Most common cause of preventable mental retardation [1]
- Low birth weight [1]
- Facial dysmorphology [1] — smooth philtrum, thin upper lip, short palpebral fissures (the classic "FAS facies")
- Growth retardation [1]
Why does alcohol cause these effects? Ethanol freely crosses the placenta and the fetal BBB. The fetus has very low ADH and ALDH activity → cannot metabolise ethanol efficiently → prolonged exposure. Ethanol disrupts neural crest cell migration (→ facial features), neuronal proliferation and migration (→ microcephaly, corpus callosum agenesis), and synaptogenesis (→ intellectual disability). There is no known safe level of alcohol in pregnancy.
| Complication | Mechanism |
|---|---|
| Impotence | Peripheral neuropathy (pelvic autonomic) + direct gonadal toxicity + hypogonadism |
| Hypogonadism and infertility | ↓ Testosterone (direct toxic effect on Leydig cells + ↑ aromatisation) → ↓ spermatogenesis |
| ↑ Breast cancer risk | Alcohol ↑ oestrogen levels; acetaldehyde is a carcinogen; alcohol impairs folate metabolism (folate is needed for DNA repair) |
I. Psychiatric Complications [1][2]
Psychiatric comorbidity in alcoholism is very common — lifetime diagnosis occurs in 55% of alcoholics [2]
- Symptoms occur while patient on heavy alcohol consumption [1]
- Symptoms subside gradually on abstinence, but may persist up to 6 months [1]
- Generalised anxiety disorders / Panic disorder / Phobic anxiety disorders / Social phobia / Obsessive compulsive disorder / PTSD [1]
- Must be distinguished from alcohol withdrawal syndrome [1]
- Chronic heavy drinkers [1]
- Auditory hallucinations [1]
- In clear consciousness [1]
- Distressing in content [1]
- Some develop schizophrenia, some remit after stopping alcohol use [1]
- Treatment with antipsychotics and advice to abstain from alcohol [1]
- Differentiate from delirium tremens: reduction in alcohol intake, clouded sensorium, visual hallucinations [1]
| Sleep pattern in alcohol-dependent patient | Sleep changes in abstinent alcoholics |
|---|---|
| ↓ Sleep latency [2] | ↑ Sleep latency [2] |
| Rebound insomnia [2] | Light and fragmented sleep [2] |
| Repeated awakening [2] | ↓ Overall sleep time with ↓ amount of deep sleep [2] |
| Tolerance with ↓ hypnotic effects by alcohol [2] | These changes persist for 2 years after abstinence [2] |
Why does alcohol disrupt sleep? Acutely, alcohol promotes sleep onset (GABA potentiation → sedation → ↓ sleep latency), but it suppresses REM sleep and disrupts sleep architecture in the second half of the night (as BAC falls, a "mini-withdrawal" hyperexcitability occurs → awakenings, vivid dreams). Chronically, tolerance develops to the sedative effect, but the sleep-disrupting effects persist. After abstinence, the upregulated excitatory systems take a very long time to re-equilibrate — hence the 2-year persistence.
Alcohol and suicide [1]:
- 7% of alcohol abusers die of suicide [1]
- Alcoholism is a factor in 30% of all completed suicides [1]
- 50% of suicide attempts have consumed alcohol at the time of the attempt [1]
- 96% of alcoholics who die by suicide continue alcohol use up to the end of their lives [1]
Why is alcohol so strongly linked to suicide? Multiple convergent mechanisms:
- Acute disinhibition — alcohol removes inhibitory control over impulsive suicidal acts (prefrontal cortex depression)
- Chronic depression — alcohol-induced mood disorder; hopelessness
- Social isolation — progressive loss of relationships, employment, purpose
- Comorbid psychiatric disorders — depression (40%), anxiety (32%), personality disorders
- Means availability — intoxicated individuals are more likely to act on suicidal thoughts with available means
- Cognitive constriction — alcohol narrows attentional focus to immediate distress, reducing ability to see alternative solutions
Alcohol and Suicide — Must Know Statistics
These lecture statistics are extremely high-yield for exams: 7% of alcohol abusers die by suicide; 30% of completed suicides involve alcoholism; 50% of suicide attempters had consumed alcohol at the time. Always assess suicide risk in every patient with alcohol misuse.
| Complication | Mechanism |
|---|---|
| Poor functioning | Cognitive impairment, withdrawal symptoms, preoccupation with drinking |
| Financial issues | Money spent on alcohol; job loss from impaired performance |
| Interpersonal problems | Disinhibited behaviour, domestic violence, relationship breakdown |
| Road traffic accidents | Impaired judgement, coordination, reaction time |
| Legal problems | Drink-driving, assault, public order offences |
Comorbid psychiatric disorders in alcoholism [1]:
- Antisocial personality disorders: 80% [1]
- Bipolar I disorder: 60% [1]
- Schizophrenia: 30% [1]
- Drug addiction: 20% [1]
- Anxiety disorders — social phobia, panic disorder [1]
When schizophrenia is comorbid [1]:
- Alcohol decreases feeling of isolation [1]
- Temporarily reduces symptoms of anxiety / depression / insomnia [1]
- BUT: increases psychotic symptoms and mood swings [1]
- Disruptive behaviour, suicide, treatment non-compliance, drug abuse, poor clinical outcome [1]
- Drug accumulation due to hepatic damage [1]
Why Hepatic Damage Matters for Psychiatric Medications
Chronic alcoholic liver disease impairs hepatic metabolism of psychiatric medications (most antipsychotics and antidepressants undergo hepatic phase I oxidation via CYP enzymes). Reduced hepatic clearance → drug accumulation → toxicity at standard doses. This is why doses of psychotropics often need to be reduced in alcoholic patients with liver disease, and why drug levels and LFTs must be monitored closely.
| System | Complications |
|---|---|
| Acute neurological | Intoxication ± blackout, traumatic brain injury, withdrawal syndrome (hallucinosis, seizures, DT), central pontine myelinolysis [2] |
| Chronic neurological | Wernicke-Korsakoff syndrome, cerebellar (vermis) degeneration, alcohol-related dementia, ↑ risk of haemorrhagic stroke, peripheral and optic neuropathy, Marchiafava-Bignami syndrome [2] |
| Gastrointestinal | Alcoholic liver disease (steatosis → hepatitis → cirrhosis → HCC), acute and chronic pancreatitis, oesophagitis, Mallory-Weiss, PUD/gastritis, malabsorption, GI malignancies [2] |
| Cardiovascular | IHD, dilated cardiomyopathy, AF, hypertension [2] |
| Haematological | Compromised immunity, macrocytosis, Zieve syndrome [2] |
| Endocrine/Metabolic | Hypoglycaemia, pseudo-Cushing's, electrolyte disturbance (hypoK, hypoNa, hypoMg, hypoPO₄), vitamin deficiencies (B1, B3, B6, B12, folate), alcoholic ketoacidosis [2] |
| Musculoskeletal | Acute and chronic myopathy, osteoporosis + fractures [2] |
| Reproductive | Impotence, hypogonadism/infertility, ↑ breast CA risk [2] |
| Fetal | IUGR, neurodevelopmental disorder, fetal alcohol syndrome [1][2] |
| Psychiatric | Dependence, personality deterioration, mood/anxiety disorders, psychotic disorders, sleep disorders, Othello syndrome, suicide [1][2] |
| Psychosocial | Poor functioning, financial issues, interpersonal problems, RTAs, legal problems [2] |
High Yield Summary
Complications of Alcohol Misuse — Key Exam Points:
- Wernicke encephalopathy: Only 20% detected in life; 20% mortality; 84% progress to Korsakoff. Triad = confusion + ophthalmoplegia + ataxia. IV thiamine 500 mg TDS × 3 days. Medical emergency.
- Korsakoff syndrome: Anterograde amnesia + confabulation. Mammillary body and medial thalamic damage. Largely irreversible.
- "Front, Back, Centre": Frontal lobe → dementia; Cerebellar vermis → ataxia; Corpus callosum → Marchiafava-Bignami.
- 6 causes of confusion in alcoholism: Intoxication, DT, Head injury, Metabolic disturbance (hypoglycaemia), Hepatic encephalopathy, Wernicke encephalopathy.
- Fetal Alcohol Syndrome: Most common cause of preventable mental retardation. Microcephaly, facial dysmorphology, growth retardation, agenesis of corpus callosum, cerebellar hypoplasia. 30% risk with heavy drinking.
- Alcohol and Suicide: 7% of alcohol abusers die by suicide; 30% of completed suicides involve alcohol; 50% of attempters consumed alcohol at the time.
- AST:ALT > 2:1 in alcoholic liver disease. ↑GGT (non-specific), ↑MCV (direct toxicity + folate deficiency), ↑CDT (most specific).
- Central pontine myelinolysis: Never correct Na⁺ faster than 10 mmol/24h.
- Alcohol-induced neurological deficit: Impaired visuospatial processing, memory impairment, EEG abnormalities, reduced cerebral blood flow and glucose metabolism.
- Psychiatric comorbidity in 55% of alcoholics; depression most common (40%); always assess suicide risk.
- Sleep disruption persists for 2 years after abstinence.
- Stroke: Light/moderate → ↓ ischaemic stroke risk (controversial); Heavy → ↑ haemorrhagic stroke risk.
Active Recall - Complications of Alcohol Misuse
References
[1] Lecture slides: GC 161. Alcohol and the Brain From Psychiatric to Neuropsychiatric Perspectives.pdf (p12, p14, p24, p28, p34, p36–44, p48) [2] Senior notes: ryanho-psych.md (sections 5.1, 5.1.1, 5.1.2; pages 96–110)
High Yield Summary
Key Concepts:
- 1 unit in HK = 10g pure ethanol; safe limits = 2 units/day (M), 1 unit/day (F)
- Neuropharmacology: Alcohol = GABA-A potentiator + NMDA inhibitor + ↑ mesolimbic DA. Chronic use → GABA-A downregulation + NMDA upregulation. Withdrawal = excitotoxic state.
- ALDH2*2 mutation is common in Asians → protective against alcoholism (flush reaction) but ↑ cancer risk if they do drink
- Cloninger Type 1 (later onset, both sexes, mild genetics) vs Type 2 (early onset, male, strong genetics, antisocial)
- Withdrawal timeline: Tremor (6–12h) → Hallucinosis (12–24h) → Seizures (12–48h) → DT (48–72h). Each successive withdrawal is worse (kindling).
- Wernicke triad: Confusion + Ophthalmoplegia + Ataxia. Give IV thiamine BEFORE or WITH glucose. Only 10% have full triad — maintain a low threshold.
- Korsakoff: Anterograde amnesia + confabulation. Mamillary bodies + medial thalamus damage. Largely irreversible.
- 6 causes of confusion in alcoholism: Intoxication, Withdrawal/DT, Wernicke, Hepatic encephalopathy, Hypoglycaemia, Subdural haematoma
- Psychiatric comorbidity in 55% of alcoholics: Depression (40%), Bipolar I (60% of bipolar patients), Antisocial PD (80% of ASPD patients), Schizophrenia (30%), Anxiety (32%)
- Diagnosing comorbid psych disorder: psychiatric disorder before alcohol onset, persistent symptoms during ≥ 4 weeks alcohol-free, FHx of psychiatric disorder
- Screening: AUDIT (best — ↑ sensitivity + specificity, 10-item WHO tool) > CAGE (↑ sensitivity only)
- Lab markers: ↑GGT (70%, non-specific), ↑MCV (60%, weeks to normalise), ↑CDT (most specific)
High Yield Summary
Differential Diagnosis of Alcohol-related Disorders — Key Exam Points:
- 6 causes of confusion in alcoholism (must memorise): Intoxication, DT, Head injury/subdural, Metabolic disturbances (hypoglycaemia), Hepatic encephalopathy, Wernicke encephalopathy
- Alcoholic hallucinosis vs DT: Hallucinosis = auditory hallucinations + clear sensorium; DT = visual hallucinations + clouded sensorium + autonomic storm
- Alcohol-induced vs primary psychiatric disorder: Use the 3 criteria — (i) psychiatric disorder before alcohol onset, (ii) persistent symptoms > 4 weeks of abstinence, (iii) FHx of psychiatric disorder
- Alcohol-induced mood disorder clears within 4 weeks of abstinence; alcohol-induced anxiety may persist up to 6 months
- The relationship is bidirectional with confounding factors — alcohol can cause, result from, or co-occur with psychiatric disorders
- Othello syndrome (morbid jealousy): a specific alcohol-related delusional disorder — beware risk of violence (56% of men)
- Always check: H'stix, BAC, NH₃, CT head, electrolytes, and timeline from last drink in any confused alcoholic
High Yield Summary
Diagnostic Criteria and Investigations — Key Exam Points:
- DSM-5 AUD: ≥ 2 of 11 criteria in 12 months. Mild (2–3), Moderate (4–5), Severe (6+). Single unified diagnosis replacing the old abuse/dependence dichotomy.
- ICD-10 Dependence: ≥ 3 of 6 criteria (compulsion, impaired control, withdrawal, tolerance, neglect, persistent use despite harm).
- Edwards & Gross: 7 elements — narrowing of repertoire, increased salience, tolerance, withdrawal, relief drinking, subjective compulsion, reinstatement after abstinence.
- DSM-5 Intoxication: Recent ingestion + behavioural change + ≥ 1 of 6 signs (slurred speech, incoordination, unsteady gait, nystagmus, attention/memory impairment, stupor/coma) + not better explained by another condition.
- Screening: AUDIT is best (10-item WHO tool, ↑ sens + spec, ≥ 8 screen positive). CAGE is quick but modest specificity.
- SADQ > 30 → inpatient detox. CIWA-Ar: < 10 very mild, 10–15 mild, 16–20 moderate, > 20 severe; guides symptom-triggered BZD therapy (start at ≥ 8).
- Lab biomarkers: ↑ GGT (70% sens, non-specific), ↑ MCV (60% sens, weeks to normalise), ↑ CDT (most specific). AST:ALT > 2:1 classic for alcoholic liver disease.
- Alcohol-induced vs comorbid psych disorder: Use 3 criteria — (i) psych disorder before alcohol, (ii) persistent symptoms > 4wk abstinence, (iii) FHx of psych disorder.
- Always get: H'stix, FBC, LFT, RFT, Mg, PO₄, coag, urine tox. CT head if confused/seizure/focal signs.
High Yield Summary
Management of Alcohol-related Disorders — Key Exam Points:
- Acute intoxication: Supportive — ABC, IV fluids, H'stix, thiamine (before or with glucose), BZD/FGA if agitated. No antidote.
- Withdrawal: BZDs are cornerstone — prefer long-acting (chlordiazepoxide, diazepam); use oxazepam/lorazepam in liver disease. Symptom-triggered dosing (CIWA-Ar ≥ 8) preferred over fixed-schedule.
- DT: Medical emergency (5% mortality). IV BZD in decreasing dosage, anticonvulsants (carbamazepine), parenteral thiamine, neuroleptics for agitation, fluid/electrolyte balance. Barbiturates/propofol for refractory cases.
- Wernicke: Medical emergency (20% mortality). IV thiamine 500 mg TDS × 3 days. Only 20% detected in life → low threshold for treatment. 84% progress to Korsakoff if untreated.
- Inpatient detox indications: SADQ > 30, Hx seizures/DT, > 30 units/day, concurrent BZD misuse, significant comorbidity.
- NICE staged approach: At-risk → brief intervention. Mild dependence → psychotherapy. Moderate/severe → acamprosate or naltrexone + psychotherapy.
- Relapse prevention drugs: Acamprosate (↓ glutamate, safe in liver disease), Naltrexone (blocks opioid reward, CI in opioid use), Disulfiram (ALDH inhibitor → aversive reaction, needs supervision), Nalmefene (PRN harm reduction).
- Psychosocial: MI (assess readiness, build motivation), CBT (identify triggers, develop coping), AA (12-step peer support), Brief intervention (at-risk drinkers).
- Treatment goals: Controlled drinking (early, non-dependent) vs Total abstinence (dependent, failed controlled drinking).
- Always treat alcohol alongside comorbid psychiatric disorders — response to psych treatment is much less likely if alcoholism is not addressed.
High Yield Summary
Complications of Alcohol Misuse — Key Exam Points:
- Wernicke encephalopathy: Only 20% detected in life; 20% mortality; 84% progress to Korsakoff. Triad = confusion + ophthalmoplegia + ataxia. IV thiamine 500 mg TDS × 3 days. Medical emergency.
- Korsakoff syndrome: Anterograde amnesia + confabulation. Mammillary body and medial thalamic damage. Largely irreversible.
- "Front, Back, Centre": Frontal lobe → dementia; Cerebellar vermis → ataxia; Corpus callosum → Marchiafava-Bignami.
- 6 causes of confusion in alcoholism: Intoxication, DT, Head injury, Metabolic disturbance (hypoglycaemia), Hepatic encephalopathy, Wernicke encephalopathy.
- Fetal Alcohol Syndrome: Most common cause of preventable mental retardation. Microcephaly, facial dysmorphology, growth retardation, agenesis of corpus callosum, cerebellar hypoplasia. 30% risk with heavy drinking.
- Alcohol and Suicide: 7% of alcohol abusers die by suicide; 30% of completed suicides involve alcohol; 50% of attempters consumed alcohol at the time.
- AST:ALT > 2:1 in alcoholic liver disease. ↑GGT (non-specific), ↑MCV (direct toxicity + folate deficiency), ↑CDT (most specific).
- Central pontine myelinolysis: Never correct Na⁺ faster than 10 mmol/24h.
- Alcohol-induced neurological deficit: Impaired visuospatial processing, memory impairment, EEG abnormalities, reduced cerebral blood flow and glucose metabolism.
- Psychiatric comorbidity in 55% of alcoholics; depression most common (40%); always assess suicide risk.
- Sleep disruption persists for 2 years after abstinence.
- Stroke: Light/moderate → ↓ ischaemic stroke risk (controversial); Heavy → ↑ haemorrhagic stroke risk.
Schizophrenia And Related Disorders
Schizophrenia and related disorders are a group of chronic psychiatric conditions characterized by disturbances in thought, perception, affect, and behavior, including symptoms such as delusions, hallucinations, disorganized thinking, and negative symptoms.
Misuse Of Substance
Misuse of substance is the harmful or hazardous use of psychoactive substances, including alcohol and illicit drugs, in a manner that deviates from approved medical or social patterns, leading to adverse physical, psychological, or social consequences.