A Behavioral Economic Analysis of Marijuana and Other Drug Use Among Heavy Drinking Young Adults.

OBJECTIVE: Behavioral economic models predict that deficits in substance-free reward and future time orientation are associated with greater drug involvement, but this hypothesis has not been systematically investigated among young adult heavy drinkers. This study evaluated the association between drug use levels (heavy drinking (HD) only, HD + marijuana use, and HD + polysubstance use) and substance-free activity engagement, future orientation, and reward deprivation (comprised of reward experience and environmental suppressors of reward) among heavy drinkers.
METHOD: Participants were 358 college students who reported two or more past-month heavy drinking episodes (5/4 or more drinks in one occasion for a man/woman). The sample was 60% women, 79% Caucasian, and the average age was 18.76 (SD = 1.07) years. Participants completed measures of alcohol and drug use, weekly time allocation to various activities, future time orientation, and reward deprivation.
RESULTS: Overall, any drug use was associated with less time spent engaged in academics and exercise, and lower future time orientation compared to HD only. Any drug use was associated with reward deprivation and HD + polysubstance use was associated with lower reward experience and environmental suppressors.
CONCLUSION: Drug use among heavy drinkers is associated with lower academic engagement and exercise, future orientation, and reward deprivation. These results provide support for behavioral economic models of drug abuse and suggest that prevention approaches should attempt to increase future orientation and availability of drug-free reward.