Head Injury and Substance Use in Young Adults.

BACKGROUND: Prior studies suggest a link between head injuries and substance use but do not routinely capture mechanisms connecting the two.

OBJECTIVES: The goal of the study was to explore whether past head injuries predicted current substance use among young adults, taking factors such as stress, self-esteem, temper, and risk-taking into consideration.

METHODS: Data were drawn from a web-based survey conducted in 2014 and 2015 at a public university in the United States (n = 897). Questions were asked about history of head injuries as well as past 12-month binge drinking, marijuana use, and prescription drug misuse. To evaluate the association between head injury and substance use, two logistic regression models were performed for each substance. Head injury was first regressed on the outcome, then related risk factors were entered into the models to determine whether they explained any association between injury and outcome.

RESULTS: A history of multiple head injuries was associated with increased odds of bingeing, marijuana, and prescription drug use. Prior delinquency and risk-taking accounted for the associations with bingeing and marijuana use. Taking all variables into consideration, multiple head injuries were associated with greater odds for prescription drug misuse.

CONCLUSIONS: Results suggest the need to give consideration to a range of concomitant variables when considering behavioral outcomes associated with head injury. Head injuries may be a marker of a constellation of risk-taking behaviors that contributes to substance use. For those with multiple injuries, misuse of prescription drugs may be an attempt to cope with lingering side effects.