According to previous studies, approximately 15% of emerging adults engage in solitary drinking. A new study examined solitary drinking (compared to normative social drinking) as a predictor of alcohol-related problems in early adulthood, as well as the role hazardous drinking as a potential mediator between solitary drinking and specific alcohol problems. Data were collected from a larger alcohol-related study of full-time students aged 18 to 25 years who reported drinking at least one, but fewer than 35, drinks per week. This sample contained 118 Canadian undergraduate students (68% female) who completed questionnaires on their drinking behaviors and harms. Measures included drinking contexts (how often they drank alone, at parties, and at bars within the past six months), alcohol problems (measured using the Young Adult Alcohol Consequences Questionnaire), and hazardous drinking (adopted from the AUDIT). Alcohol problems were organized into eight domains: social-interpersonal, impaired control, diminished self-perception, poor self-care, risky behavior, academic/occupations, physical dependence, and blackout drinking. Data were analyzed using path modeling to test the unique associations between drinking contexts (predictors) and alcohol problem domains (outcomes), with hazardous drinking as a mediator. Robust maximum likelihood estimation was used to correct for non-normal distributions of variables. Results indicated this sample had comparable levels of hazardous drinking, slightly fewer alcohol problems, and similar means for solitary and social drinking, compared to previous undergraduate samples. The model was found to be an excellent fit. Confidence intervals (CIs) showed solitary drinking was a positive predictor of hazardous drinking, but did not support associated between social (parties and bars) drinking and hazardous alcohol use. CIs also showed hazardous drinking was a positive predictor of all eight domains of alcohol problems. Analysis of indirect effects using CIs found solitary drinking positively predicted all domains of alcohol problems via hazardous drinking. Effect sizes showed drinking alone was an especially important predictor of domains involving risky behaviors and blackout drinking; solitary drinking accounted for over 20% of the variance in these outcomes. There was no evidence of indirect effects from social drinking at bars to alcohol problems via hazardous drinking, but smaller indirect effects were observed for drinking at parties in four problem domains.
Take away: The results of this study support hazardous drinking as a mediator of the effects of drinking alone on alcohol problems. For alcohol problems in risky behavior and blackout drinking domains, solitary drinking accounted for 20% of the variation in outcomes.