Mortality associated with illegal drug use among adults in the United States

To examine all-cause and cause-specific mortality over a 15-year follow-up period in relation to at-baseline reported lifetime use of illegal drugs from five classes (marijuana, cocaine, heroin, hallucinogens, and inhalants) among adults in the United States (US) household population.

The study involved 20,983 sample adults who responded to the 1991 National Health Interview Survey Drug and Alcohol Use supplemental questionnaire and also met the eligibility criteria for mortality follow-up. Cox proportional hazards models were estimated to examine the relationships.

Adults who at baseline reported lifetime heroin use were at significantly higher risk of all-cause death over the follow-up period (hazard rate ratio or HR = 2.02; 95% confidence interval or CI 1.26-3.23), compared with those who did not report using drugs from any of the five classes, even after adjusting for age, sex, race, education, marital status, cigarette smoking status, and alcohol use status. Those who at baseline reported lifetime cocaine (no heroin) use had a significantly higher rate of death associated with human immunodeficiency virus diseases over the follow-up period than nonusers of drugs from any of the five classes. Several limitations of the analysis are discussed.

Further research is needed to understand and track the elevated mortality associated with illegal drug use and the correlates of drug-poisoning deaths.