Daily-Level Drinking Motives as Predictors of Transdermal Alcohol Concentration and Alcohol-Induced Blackouts Among Young Adults.

BACKGROUND

Alcohol use is necessary-but not sufficient-for understanding why individuals experience an alcohol-induced blackout (AIB). Drinking motives are one of the most proximal risk factors for alcohol use. This study conducts a comprehensive within-person examination of AIBs predicted by prospective daily reports of drinking motives and alcohol use measured using a transdermal alcohol concentration (TAC) biosensor.

METHODS

Participants were young adults who engaged in risky drinking and experienced at least 1 AIB in the past 3-months (N = 169, Mage = 20.8, 53% female, 87% White, 10% Hispanic). They wore TAC biosensors and completed twice daily surveys about drinking motives and AIBs over six social weekends (i.e., Thursday-Sunday). TAC drinking features (peak, rise rate, and rise duration) were extracted from TAC data for each day. Two-level multilevel structural equation models were conducted to examine the associations between drinking motives, latent intoxication estimated from TAC features, and AIBs. Aim 1 examined separate models for each motive (enhancement, social, coping, conformity). Aim 2 examined a single model with each motive adjusting for the others.

RESULTS

In Aim 1, on days when participants reported higher enhancement, social, coping, and conformity motives, the associated increase in TAC intoxication was associated with increased odds of experiencing an AIB. In Aim 2, when all motives were entered into a single model, only social motives resulted in increased TAC, which subsequently increased the odds of an AIB occurring.

CONCLUSIONS

Findings demonstrate that days when an individual reports above average drinking motives relative to their own average, they are at increased risk of engaging in riskier drinking, which may result in subsequent AIBs. These findings suggest that daily changes in drinking motives may be an important intervention pathway for preventing risky drinking and subsequent AIBs.