Substance use behaviors in the daily lives of U.S. college students reporting recent use: The varying roles of romantic relationships.

rationaleWhile the detrimental consequences of problematic substance use behaviors in early adulthood are well-documented, the interpersonal predictors of substance use in the naturalistic context of daily life are less known.

methodsUsing ecological momentary assessments to capture moments of binge drinking, marijuana use, nicotine use, and prescription misuse in everyday life, this study explored the romantic relationship contexts (status, quality, partner presence) of substance use among young adults (aged 18-21) attending a university in the Midwestern U.S. Between 2017 and 2019, 296 participants, who had endorsed recent substance use at screening for a larger study on prescription misuse, completed four reports per day for approximately 28 days, resulting in over 23,000 reports for this investigation.

resultsRelationship status, partner support, and partner presence in the moment were all associated with at least one type of substance use behavior. Generalized multilevel models indicated that partnered participants engaged in less marijuana use, nicotine use, and prescription misuse in daily life compared to single participants. Higher partner support predicted less binge drinking, yet also predicted higher nicotine use and prescription misuse. When with a romantic partner in daily life, partnered participants were more likely to engage in binge drinking and marijuana use, and less likely to misuse prescription drugs. Nicotine use was more likely when with a partner, but only if partner support was high.

conclusionsFindings highlight the intricate links between interpersonal contexts and substance behaviors and indicate supportive relationships are not universally protective against substance use among this population.