Cannabis and Cocaine, Heroin, or Methamphetamine Use and Factors Associated with Multiple Drug Use and Drug Treatment in a Nationally Representative Sample

Cannabis is often used with other illicit drugs. Drawing from leading theories of polysubstance use, we used data from the 2009-2018 National Health and Nutrition Examination Survey to examine the prevalence of reported lifetime use of cannabis and cocaine, heroin, and/or methamphetamine among non-pregnant respondents ages 18-59 years. After identifying the subpopulation that reported using multiple drugs, we used multivariate logistic regression analysis to identify their demographic characteristics and factors associated with drug treatment participation. Within our analytic sample (<i>N</i> = 16,946), 18.7% reported lifetime cannabis use and cocaine, heroin, or methamphetamine use; 1.4% reported using all four of these drugs in their lifetime. Among individuals who reported using multiple drugs, 21.3% reported drug treatment participation. Compared to respondents who had never been in drug treatment, those who had been had higher odds of being non-Hispanic Black (AOR = 2.0, 95% CI 1.5-2.8), being in fair/poor health (AOR = 1.5, 95% CI 1.1-1.9), and reporting more medical conditions (AOR = 1.2, 95% CI 1.1-1.4). Being female, Mexican American, married, and a non-citizen lowered the odds of drug treatment. Having more than a high-school education and having a household income of more than $100,000 also reduced the odds of drug treatment.