Effects of alcohol sensitivity on alcohol-induced blackouts and passing out: An examination of the alcohol sensitivity questionnaire among underage drinkers.

Abstract

The role of alcohol sensitivity in the experience of blacking out and passing out has not been well established. Here, we examined the relation between individual differences in alcohol sensitivity (i.e., numbers of drinks required to experience various effects of alcohol) and reports of blacking out and passing out in the past year. Participants (925 healthy, underage college student drinkers) completed the Alcohol Sensitivity Questionnaire (ASQ) and reported on their past year blacking out and passing out experiences. The fit of the ASQ's 2-factor structure was fair (CFI=0.90, RMSEA=0.09) in this sample of underage drinkers. In unadjusted models, higher ASQ scores (i.e., requiring more drinks to experience effects, indicating lower alcohol sensitivity) were associated with experiencing more blackouts (IRR=1.68 [1.31-2.15]) and passing out (IRR=2.25 [1.59-3.18]) in the past year. After controlling for typical consumption, however, higher ASQ scores were associated with fewer past-year blackouts (IRR=0.76 [0.60-0.98]). Total ASQ scores moderated the relationship between typical alcohol consumption and blackout occurrence (interaction IRR=0.96 [0.93-0.98]), but not passing out occurrence (interaction IRR=0.95 [0.89-1.01]), with the quantity of alcohol consumed more strongly associated with blackout occurrence among higher-sensitivity than lower-sensitivity drinkers. These findings are consistent with prior work suggesting that low sensitivity may act as a paradoxical risk factor for certain heavy drinking effects, contributing to higher levels of alcohol consumption and more frequent negative consequences while also conferring protection (relative to high-sensitivity peers) at a given level of alcohol exposure.