Alcohol and drug use in suicidal behaviour

Abstract

To present a summary of estimates of the risk of suicidal behaviour (ideation, plan and attempt) among those with substance use disorders in the general population and risk estimates for those with acute alcohol and drug consumption (intoxication) immediately prior to a suicide attempt. In Mexico and elsewhere studies have emerged on the risk of suicidal behaviour among those with substance use disorders that are not affected by treatment selection bias or by psychiatric comorbidity. In developed and developing groups of nations, alcohol use disorders were associated with increased odds ratio (OR) of ideation (range 2.0-2.5) and attempt (2.6-3.7), whereas drug use disorders were associated with increased risk of ideation (2.3-3.0) and attempt (2.0-4.0). Follow-up studies of general population samples reported an OR for drug use disorders from 1.9 to 3.7 for ideation, and an OR of 3.0 for attempt. Alcohol dependence increased suicide ideation with an OR of 1.5. Those drinking alcohol prior to the suicide attempt had ORs in the range of 6.2-9.6. This increase may have a dose-response relationship. We found no studies providing risk estimates for drug use prior to a suicide attempt. Current evidence points to a causal role of alcohol and drug use disorders exerting a distal effect on suicidal behaviour. Evidence for the proximal role of alcohol and drug use, as triggers of suicidal behaviour, are still very limited in number, analytical techniques and scope of substances other than alcohol.