Shift in Drug vs Alcohol Prevalence in Milwaukee County Motor Vehicle Decedents, 2010-2016

The purpose of this study is to examine the prevalence of alcohol and nonalcohol drugs in motor vehicle crash (MVC) decedents in Milwaukee County, Wisconsin.

A retrospective review of MVC decedents in Milwaukee County from 2010 to 2016 was performed. Substances were divided into 5 categories based on chemical composition and clinical effects: alcohol, cocaine and its metabolite benzoylecgonine, opioids, cannabinoids, amphetamines and methamphetamines. Decedents were determined to be positive if any of these substances were detected on blood toxicology analysis.

Sixty-five percent (n = 113) of MVC decedents tested positive for 1 substance, while polysubstance use (≥ 2 substances) was seen in 27% (n = 47). Alcohol was the most prevalent substance (n = 77, 44%), while cannabinoids were the second most prevalent (n = 50, 29%), and opioids were third most prevalent (n = 24, 14%). There was a statistically significant increase in the number of MVC decedents who tested positive for opioids from 2010 to 2016 (slope = 3.9, P < 0.01). The number of decedents who tested positive for alcohol only from 2010 to 2016 decreased significantly (slope = -3.9, P < 0.05), and 2016 was the first year in which the number of drug-positive decedents exceeded the number of alcohol-positive decedents.

The prevalence of drugs exceeded that of alcohol in decedents for the first time in 2016 in Milwaukee County. While continued efforts to reduce alcohol-positive driving are encouraged, increased attention to drugged driving is needed to prevent further drug-positive fatalities.