TextbookSubstance MisuseAlcohol Use Disorder

Alcohol Use Disorder

Alcohol use disorder (AUD) is a chronic relapsing condition characterised by impaired control over alcohol use, with physical and psychological dependence, affecting approximately 600,000 dependent drinkers in England.

Key Facts

AUDIT (Alcohol Use Disorders Identification Test) is the WHO-validated screening tool; score ≥8 indicates hazardous drinking, ≥20 suggests possible dependence NICE CG115 recommends brief interventions for hazardous/harmful drinking and specialist referral for moderate-severe dependence SADQ (Severity of Alcohol Dependence Questionnaire): <16 mild, 16-30 moderate, >30 severe dependence UK Chief Medical Officers' guideline: no more than 14 units/week, spread over ≥3 days with alcohol-free days Acamprosate (333 mg TDS) and naltrexone (25-50 mg OD) are first-line relapse prevention pharmacotherapies Alcohol-related deaths in England: approximately 10,000/year; liver disease is the 3rd leading cause of premature death in working-age adults ICD-11 Dependence Syndrome: impaired control, physiological features (tolerance/withdrawal), persistent use despite harm FRAMES model for brief intervention: Feedback, Responsibility, Advice, Menu of options, Empathy, Self-efficacy

Overview

Key Facts

Alcohol use disorder encompasses a spectrum from hazardous drinking to severe dependence. The UK has one of the highest rates of alcohol consumption in Europe. Alcohol misuse costs the NHS approximately £3.5 billion/year and is associated with over 200 disease and injury conditions.

Epidemiology

  • Approximately 600,000 dependent drinkers in England; only ~18% access treatment
  • Prevalence of hazardous drinking (AUDIT ≥8): approximately 25% of the adult population
  • Male:female ratio approximately 2:1 for dependence
  • Peak age of alcohol-related hospital admissions: 55-64 years
  • Alcohol-specific deaths rising: 9,641 in England and Wales (2021) — highest on record
  • Socioeconomic deprivation strongly associated with alcohol harm (the alcohol harm paradox)

Aetiology

  • Genetic factors: heritability ~50-60%; polymorphisms in ADH1B and ALDH2 genes influence risk
  • Neurobiological: alcohol enhances GABA (inhibitory) and inhibits glutamate (excitatory) neurotransmission; chronic use leads to neuroadaptation
  • Psychological: co-morbid anxiety, depression, PTSD, ADHD; adverse childhood experiences (ACEs)
  • Social/environmental: peer influence, availability, pricing, cultural norms, socioeconomic deprivation
  • Behavioural: positive and negative reinforcement models; classical and operant conditioning

Pathophysiology

  • Chronic alcohol exposure → upregulation of NMDA glutamate receptors and downregulation of GABA-A receptors
  • Abrupt cessation → unopposed excitatory neurotransmission → withdrawal syndrome
  • Hepatic metabolism: alcohol → acetaldehyde (via alcohol dehydrogenase) → acetate (via aldehyde dehydrogenase)
  • Chronic use induces CYP2E1 (microsomal ethanol oxidising system), generating reactive oxygen species
  • Progressive hepatotoxicity: steatosis → steatohepatitis → fibrosis → cirrhosis

Clinical Presentation

Hazardous and Harmful Drinking

  • May be asymptomatic or present with social/occupational consequences
  • Incidental findings: raised GGT, raised MCV, abnormal LFTs
  • Recurrent injuries, accidents, or attendances to Emergency Department

Alcohol Dependence

  • Compulsion: strong desire or sense of compulsion to drink
  • Impaired control: difficulty controlling onset, termination, or levels of use
  • Tolerance: need for increased amounts to achieve desired effect
  • Withdrawal: physiological withdrawal state on cessation or reduction
  • Neglect: progressive neglect of alternative activities and responsibilities
  • Persistence: continued use despite clear evidence of harmful consequences

Physical Complications

  • Hepatic: fatty liver, alcoholic hepatitis, cirrhosis, hepatocellular carcinoma
  • Gastrointestinal: pancreatitis (acute and chronic), oesophageal varices, Mallory-Weiss tears, gastritis
  • Neurological: peripheral neuropathy, Wernicke encephalopathy, Korsakoff syndrome, cerebellar degeneration
  • Cardiovascular: dilated cardiomyopathy, atrial fibrillation, hypertension
  • Haematological: macrocytosis, thrombocytopenia, folate deficiency
  • Metabolic: hypomagnesaemia, hypophosphataemia, hypoglycaemia

Red Flags

  • Delirium tremens (onset 48-72 hours post-cessation): confusion, visual hallucinations, autonomic instability — mortality 5-15% if untreated
  • Wernicke encephalopathy: ophthalmoplegia, ataxia, confusion — requires immediate IV Pabrinex
  • Acute alcoholic hepatitis: jaundice, coagulopathy, encephalopathy — Maddrey DF ≥32 indicates severe disease
  • Variceal haemorrhage: massive upper GI bleed — mortality 15-20% per episode
  • Alcohol-related brain damage: cognitive impairment, personality change, self-neglect

Differential Diagnosis

DiagnosisKey FeaturesInvestigation
Depression/anxietyLow mood, anhedonia, sleep disturbance; may co-existPHQ-9, GAD-7, psychiatric assessment
Hepatitis B/CSimilar LFT pattern, risk with IVDUHepatitis serology
Non-alcoholic fatty liver diseaseMetabolic syndrome, obesity, similar LFTsUSS liver, metabolic screen
Drug misuseConcurrent substance use commonUrine drug screen
Thyroid diseaseFatigue, weight change, tremorTFTs
Diabetes mellitusPolyuria, polydipsia, neuropathyHbA1c, fasting glucose
Cerebellar pathologyAtaxia, nystagmus (non-alcohol cause)MRI brain
Pancreatic malignancyWeight loss, abdominal pain, jaundiceCT abdomen, CA 19-9

Diagnosis / Investigation

Bedside

  • AUDIT questionnaire: 10-item screening tool; score ≥8 hazardous, ≥16 harmful, ≥20 possibly dependent
  • AUDIT-C: abbreviated 3-item version for primary care screening
  • SADQ: 20-item severity assessment for dependence (score 0-60)
  • Breath alcohol level: may be useful in acute settings
  • Clinical Institute Withdrawal Assessment (CIWA-Ar): monitors withdrawal severity

Bloods

  • LFTs: raised GGT (most sensitive marker), raised AST (AST:ALT ratio >2 suggests alcoholic liver disease)
  • FBC: macrocytosis (raised MCV), thrombocytopenia
  • Clotting: prolonged INR/PT suggests significant liver disease
  • U&Es: hyponatraemia, hypokalaemia, hypomagnesaemia
  • Phosphate: hypophosphataemia (refeeding risk)
  • Carbohydrate-deficient transferrin (CDT): biomarker of heavy drinking over 2-3 weeks
  • Ethyl glucuronide (EtG): urine or hair testing for recent alcohol use
  • Serum B12 and folate: commonly deficient

Imaging

  • Liver ultrasound: assess for steatosis, fibrosis, cirrhosis, hepatocellular carcinoma
  • FibroScan (transient elastography): non-invasive assessment of liver fibrosis; >8 kPa suggests significant fibrosis
  • CT head: if concern about subdural haematoma, cerebellar degeneration, or Wernicke encephalopathy (MRI preferred for Wernicke)

Special Tests

  • Liver biopsy: gold standard for staging liver disease (rarely needed with FibroScan)
  • Upper GI endoscopy: if varices suspected or upper GI bleed
  • EEG: if seizure aetiology uncertain
  • Neuropsychological testing: if alcohol-related brain damage suspected

Management

Non-pharmacological

  • Brief intervention (NICE CG115): 5-15 minute structured advice for hazardous/harmful drinkers; NNT ~8 for reduction to low-risk drinking
  • Extended brief intervention: up to 4 sessions of motivational interviewing-based counselling
  • Cognitive behavioural therapy (CBT): addresses maladaptive thought patterns and drinking triggers
  • Mutual aid: Alcoholics Anonymous (12-step), SMART Recovery (CBT-based)
  • Social support: housing, employment, relationship counselling
  • Nutritional support: high-calorie diet, thiamine supplementation

Pharmacological

  • Assisted withdrawal (NICE CG115):
    • Chlordiazepoxide: first-line for community/inpatient detoxification; typical reducing regimen over 7-10 days (e.g. 30 mg QDS reducing by 20% daily for moderate dependence)
    • Diazepam: alternative benzodiazepine; symptom-triggered regimens used in some units
  • Thiamine supplementation:
    • Oral thiamine 100 mg TDS for mild/moderate risk
    • IV Pabrinex (2 pairs TDS for 3-5 days) for high-risk patients or suspected Wernicke encephalopathy
  • Relapse prevention (NICE CG115):
    • Acamprosate 666 mg TDS (333 mg TDS if <60 kg): modulates glutamate; start after detoxification; continue for 6 monthsCOMBINE trial showed efficacy combined with behavioural therapy
    • Naltrexone 25 mg OD for 3 days then 50 mg OD: opioid antagonist; reduces reward from drinking — can cause hepatotoxicity; check LFTs
    • Disulfiram 200 mg OD: aldehyde dehydrogenase inhibitor; causes acetaldehyde accumulation with alcohol — supervised consumption recommended
    • Nalmefene 18 mg PRN: licensed for reduction of alcohol consumption in adults with alcohol dependence without withdrawal symptoms (NICE TA325)

Surgical

  • Liver transplantation: considered for end-stage alcoholic liver disease with minimum 6 months abstinence (although increasingly flexible) — 5-year survival ~70%
  • TIPSS (transjugular intrahepatic portosystemic shunt): for recurrent variceal haemorrhage or refractory ascites

Referral Criteria

  • Specialist alcohol services: moderate-severe dependence (SADQ ≥16), previous complicated withdrawal, co-morbid mental or physical health problems
  • Inpatient detoxification: severe dependence (SADQ >30), history of withdrawal seizures or delirium tremens, significant co-morbidity, unstable social situation
  • Hepatology: suspected cirrhosis, Maddrey DF ≥32, liver transplant assessment
  • Psychiatry: co-morbid severe mental illness, suicidality, dual diagnosis

Prognosis

Mortality and Outcomes

  • Alcohol-specific mortality in England: approximately 14.8 per 100,000 population (2021)
  • Delirium tremens mortality: 5-15% untreated, <1% with appropriate treatment
  • Alcoholic hepatitis (Maddrey DF ≥32): 28-day mortality 30-50% without treatment; Glasgow Alcoholic Hepatitis Score ≥9 predicts poor prognosis
  • Alcoholic cirrhosis: 5-year survival ~50% if drinking continues, ~70% with abstinence
  • Alcohol-related brain damage: affects up to 35% of heavy drinkers to some degree; often irreversible

Complications

  • Liver cirrhosis and hepatocellular carcinoma: risk increases with cumulative lifetime consumption
  • Oesophageal varices: present in ~50% of patients with cirrhosis; 15-20% mortality per bleed
  • Pancreatitis: alcohol is the cause in ~30-40% of acute pancreatitis cases in the UK
  • Wernicke-Korsakoff syndrome: Wernicke encephalopathy is under-diagnosed; ~80% of untreated cases progress to Korsakoff syndrome
  • Foetal alcohol spectrum disorder: leading preventable cause of intellectual disability; no safe level of alcohol in pregnancy
  • Cancer risk: increased risk of oral, pharyngeal, oesophageal, liver, breast, and colorectal cancers

Other Relevant Information

AUDIT Scoring

ScoreRisk CategoryIntervention
0-7Lower riskInformation and brief advice
8-15Increasing risk (hazardous)Brief intervention
16-19Higher risk (harmful)Extended brief intervention
20-40Possible dependenceReferral to specialist services

SADQ Scoring

ScoreSeverityManagement
0-15MildCommunity detoxification
16-30ModerateCommunity or inpatient detoxification
31-60SevereInpatient detoxification

UK Units Calculation

DrinkApproximate Units
Pint of beer/lager (4%)2.3 units
Pint of strong lager (5.2%)3 units
Large glass of wine (250 ml, 13%)3.3 units
Single spirit measure (25 ml, 40%)1 unit
Bottle of wine (750 ml, 13%)10 units

Landmark Trials

TrialYearKey Finding
COMBINE2006Naltrexone + behavioural therapy effective; acamprosate less effective in this US population
STOPAH2015Prednisolone may reduce 28-day mortality in severe alcoholic hepatitis; pentoxifylline showed no benefit
UKATT2005Motivational enhancement therapy and social behaviour and network therapy equally effective in UK NHS
Project MATCH1997CBT, motivational enhancement, and 12-step facilitation all effective; no matching effect