Serious harm reduction protective behavioral strategies reduce consequences associated with alcohol-induced blackouts in college students

Objective: Alcohol-induced blackouts (AIBs) have been associated with increased alcohol-related consequences. Serious harm reduction (SHR) protective behavioral strategies may reduce consequences when students are drinking heavily. We examined whether SHR weakened the relationship between AIBs and a) total consequences and b) serious consequences (e.g., sexual assault) only. Methods: Students were eligible if they were aged 18–22 years, in their second or third year of college, reported drinking 4 + drinks on a typical Friday or Saturday, experienced ≥ 1 AIB in the past semester, owned an iPhone, and were willing to wear a sensor for 3 days each weekend. Students (N = 79, 55.7 % female, 86.1 % White, Mage = 20.1) wore sensors and completed daily diaries over four consecutive weekends (852 total surveys; 89.9 % completion rate). Linear multilevel models were conducted to test for moderating effects of SHR. Results: SHR weakened the association between AIBs and total consequences. At low (−1 SD) SHR, days with an AIB had an additional 1.46 consequences compared to days without an AIB, on average. At high (+1 SD) SHR, days with an AIB had an additional 0.94 consequences compared to days without an AIB, on average. SHR did not change the association between AIBs and serious consequences. Conclusions: Students experienced approximately 50% more consequences on nights when they had an AIB and used below average numbers of SHR compared to nights when they had an AIB and used above average numbers of SHR. These findings suggest that student drinking interventions should include SHR to reduce harm associated with drinking and AIBs.