BACKGROUND: Factors related to risky drinking (e.g., motives, protective behavioral strategies [PBS]) may vary between youth who engage in polysubstance use compared to those who consume alcohol only. We examined differences in factors among youth who consume alcohol only compared to alcohol with other substances (i.e., polysubstance use), and correlates associated with risky drinking between the groups. METHODS: Participants (N = 955; ages 16-24; 54.5% female) who reported recent risky drinking completed measures of alcohol/substance use, alcohol-related consequences, drinking motives, alcohol PBS, mental health symptoms, and emotion dysregulation. Participants were in the polysubstance group if they reported using at least one other substance (e.g., cannabis, stimulants) in addition to alcohol in the past three months. Chi-square and t-tests examined differences between the two groups and multiple regression analyses examined correlates of risky drinking. RESULTS: Most participants (70.4%, n = 672) reported polysubstance use; these individuals engaged in riskier patterns of drinking, experienced more alcohol-related consequences, used fewer PBS, had stronger drinking motives (enhancement, social, coping), endorsed more mental health symptoms, and reported more emotion dysregulation. Regression models showed that emotion dysregulation significantly associated with risky drinking in the alcohol-only group; conformity and coping motives, alcohol PBS, and anxiety symptoms significantly associated with risky drinking in the polysubstance group. CONCLUSIONS: Among risky drinking youth, results indicated youth engaging in polysubstance use have greater comorbidities and individual-level factors associated with risky drinking than youth who consume alcohol only. These findings may inform the tailoring of interventions for individuals who engage in risky drinking and polysubstance use.

Purpose

Alcohol use among adolescents and emerging adults is an important public health issue requiring prevention approaches. Herein, we describe outcomes from a randomized controlled trial testing the efficacy of group-based social media interventions targeting risky drinking among youth.

Procedures

Using social media advertisements to screen potential participants, we recruited 955 youth (ages 16-24) reporting recent risky drinking. After completing a baseline assessment, participants were randomized to 8-week secret Facebook group conditions: Social Media Intervention + Incentives for engagement, Social Media Intervention only, and attention-placebo control. Electronic coaches trained in motivational interviewing facilitated interaction in intervention groups. Primary outcomes include past 3-month alcohol use and consequences over 3-, 6-, and 12-month follow-ups. Secondary outcomes include other drug use, consequences, and impaired driving. We also measured intervention engagement and acceptability.

Results

The interventions were well-received, with significantly greater acceptability ratings and engagement in the SMI+I condition relative to other groups. In adjusted analyses, there were no significant differences between interventions and control on alcohol-related outcomes, with all groups showing reductions. Regarding secondary outcomes (70.4% used other drugs), compared to control, the incentivized group reduced other drug use, consequences, and cannabis-impaired driving; the non-incentivized group did not significantly differ from the control condition.

Conclusions

Among this predominantly poly-substance using sample, findings were mixed, with significant effects of the incentivized social media intervention on drug (but not alcohol) outcomes. Future studies are needed to further refine social media-delivered interventions to reduce alcohol and other drug use.

Trial registration

ClinicalTrials.gov NCT02809586; University of Michigan HUM#00102242.