Epidemiology of addictive disorders: a brief review MRCPsych addiction psychiatry seminar series Dr Stuart McLaren 2 nd March 2012

consumption /use dependence problems/harms Epidemiology of substance use

Prevalence of psychiatric disorders, % adult population Common mental disorders16.2 Psychosis 0.4 Alcohol dependence 5.9 Drug 9.2 APMS 2007

Lifetime prevalence of drug use, % of adult population Overall35.5 Cannabis30 Amphetamines12 Cocaine 7.7 Ecstasy 7.3 Opiates<1 2006/2007 BCS

Prevalence rate of heroin and crack cocaine users in England per 1000 population aged 15 to 64 by gender Rate95% CI Male Female Hay et al. 2007

Prevalence of drug dependence, % adult population All3.4 Cannabis only2.5 Other drugs APMS

Prevalence of injecting in England per 1000 population aged 15 to 64 Rate95% CI /10 NDEC

Main drug in adult treatment populations (n=174250) Heroin66% Crack 6% Cocaine 6% Methadone 8% Cannabis 7% NDTMS 2007/8

Illicit drug trends Drug dependence stable since 2000 Increasing multiple drug use Opiate use stable, may be falling in young Use of opiates correlates with deprivation Cannabis use may be falling Use greater in lower income groups

Psychiatric co-morbidity 70% of opiate users have another current psychiatric disorder Drug dependency strongly associated with: ASPD BPD 2007 APMS

Substance related harms and risks ‘with drugs nothing is always. Their use does not carry a guarantee of danger, but neither is their safety guaranteed. What one needs to ask about any substance is not whether in absolute terms it is safe, but rather the degree of risk which may attach to its use.’

Health consequences of drug use Acute toxic effects, including overdose Acute intoxication effects, including accidental injury and violence Dependence Adverse health effects of chronic, regular use, including chronic disease, BBVs and mental disorder

Risky periods for opiate users Risk increases during periods of transition: Release form prison (SMR ~8) Early in substitute treatment (x3 increase compared with later treatment) Following discharge from methadone maintenance treatment (MRR ~10 in first 2 weeks)

consumption /use dependence problems/harms Epidemiology of drinking and alcohol-related harm

Consumption and risk – units/week MenWomen Low risk<21<14 Hazardous drinking Harmful drinking>50>35

Prevalence of hazardous and harmful drinking, % adult population hazardous harmful AUDIT score 8 or more 16 or more M386 F152 All253.8 APMS 2007

Prevalence of alcohol dependence in last 6/12 - % of adult population MFAll Mild Moderate Severe Overall APMS

Psychiatric co-morbidity 37% of those with alcohol use disorders have another mental disorder Alcohol dependence is strongly associated with ASPD moderately associated with BPD and drug dependence 2007 APMS

Alcohol trends CAGE scores increasing between generations of men Dependence and hazardous drinking peak in middle occupations Heavy drinking shows no clear class gradient Younger people and women at particular risk

1. Risk factors for drug use Social factors –Availability –Early use of tobacco and alcohol –Disadvantaged background Family factors –Poor parent-child relationships –Parental conflict –Parental dug use

2. Risk factors for drug use Individual factors: male novelty seeking personality early conduct disorder poor school performance/early school leaving Affiliation with antisocial and drug-using peers Above factors often co-occur

Risk factors for drug dependency Early onset of drug use Multiple drug use Mental health disorders before the age of 15 years (conduct disorder and depression)

Addiction careers ‘the period in which substance use causes problems’ Lifetime use (%)Lifetime dependence (%) Capture rate Tobacco Heroin Alcohol921415

Clinical course of alcohol dependence Age of: First drink*13-15 years First intoxication*15-17 years First problem*16-22 years Onset of dependence25-40 years Age of death60 years * Same as general population