Cumulative Alcohol Metabolism Genetic Score as a Moderator of the Association Between Positive Drinking Consequences and Next-Day Alcohol Use: An Observational Study.

Positive outcomes that college students experience after drinking alcohol can motivate them to drink in the future. However, college students may respond to similar alcohol-related experiences differently according to genetic variability in their alcohol metabolism genes. This study investigated the effects of a cumulative genetic score (CGS) comprising alleles in ALDH2 rs671, ADH1B rs1229984 and ADH1C rs1693482 on relationships between positive drinking consequences and next-day drinking behaviours. The current study used daily diary assessments from 120 Korean college students (35% male, age range = 18-25) to examine the interactive effects of CGS and positive drinking consequences on alcohol quantity and frequency over 14 days. Multilevel modelling revealed that individuals with higher CGS drank more frequently and consumed a greater number of drinks the next day following positive drinking experiences. In contrast, individuals with lower CGS either did not drink or drank less the next day, even if they had positive drinking experiences on the previous day. Our findings indicate that the effects of positive drinking consequences on next-day drinking behaviours vary according to cumulative genetic risk across ALDH2, ADH1B and ADH1C. These findings may suggest a benefit to genotype-specific interventions for college students' alcohol consumption in response to positive drinking experiences.