The potential role of cocaine and heroin co-use in the opioid epidemic in the United States

Abstract

Introduction: Opioid/heroin use is an epidemic in the United States (US). Polysubstance use dramatically increases risk of adverse overdose outcomes, versus use of a single substance. Co-use of heroin and cocaine, known as "speedballing," is associated with higher risk of overdose than use of either alone. It is not known whether co-use relative to use of either alone has increased in the US in recent years at a national level. If so, this may be one contributing factor to the increasing fatality rate associated with the US opioid epidemic. This study investigated the prevalence of use of each and co-use of heroin and cocaine from 2002 to 2017 in the US.

Methods: Data were drawn from the 2002 to 2017 National Survey on Drug Use and Health (NSDUH) to estimate prevalence of past-month heroin use, cocaine use, and co-use of heroin and cocaine among Americans ages 12 and older.

Results: From 2002 to 2017, cocaine use (without heroin) (adjusted odds ratio (AOR) = 0.971, 95% confidence interval (0.963, 0.979)) declined overall, though a subsequent quadratic analysis suggested that it began increasing in 2011. In contrast, heroin and cocaine co-use (AOR = 1.062 (1.027, 1.099)) and heroin use (without cocaine) (AOR = 1.101 (1.070, 1.133)) linearly increased from 2002 to 2017.

Conclusions: Screening, outreach, clinical treatment, and first responders should be aware of increasing patterns of polysubstance use and the potential implications of co-use of heroin and cocaine on first responders' intervention and the potential role of increasing exposure to multiple substances on overdose outcomes in the US.

Keywords: Cocaine; Heroin; NSDUH; Opioid; Polysubstance; Speedball.