Genotype-based feedback on alcohol metabolism and its association with hazardous drinking among municipal employees: a pilot observational study

Background Our previous study showed that feedback on alcohol-metabolizing genotypes, combined with a personalized brief intervention, reduced alcohol consumption among young adults with excessive drinking. However, it remains unclear whether providing genotype-based educational materials without individualized counseling is associated with changes in alcohol-related behaviors in occupational settings. This study examined changes in alcohol-related behaviors following genotype-based educational feedback among Japanese municipal employees. Methods This single-arm observational pilot study enrolled 136 employees aged 20–60 years at baseline, of whom 127 underwent saliva-based genotyping for aldehyde dehydrogenase 2 ( ALDH2) and alcohol dehydrogenase 1B ( ADH1B). Participants with available genotype results received individualized genotype feedback and a standardized educational pamphlet containing genotype-specific information on alcohol sensitivity, associated health risks, and drinking-related guidance. Alcohol-related outcomes were assessed at baseline and approximately 1 month after feedback. The primary outcome was mean alcohol consumption per drinking day. Secondary outcomes included binge episodic drinking frequency, Alcohol Use Disorders Identification Test-Consumption (AUDIT-C) scores, behavioral modification stage, subjective health, and perceived health competence. Paired data from 112 follow-up completers were analyzed. Results Neither alcohol consumption per drinking day nor binge episodic drinking frequency changed significantly after genotype feedback ( p = 0.3586 and p = 0.2491, respectively). The AUDIT-C total score decreased significantly ( p = 0.0276), and the decrease in the AUDIT-C Question 3 score remained significant after Bonferroni correction for the three item-level comparisons (adjusted p = 0.0258). The total Perceived Health Competence Scale score did not change significantly ( p = 0.4900). Among the eight PHCS items, only Question 7 showed a significant change after Bonferroni correction (adjusted p = 0.0210). No significant changes were observed in behavioral modification stage or subjective health. Conclusions Although genotype-based educational feedback alone was not associated with reduced overall alcohol consumption, it was associated with decreases in the AUDIT-C total score and the frequency of consuming six or more drinks on one occasion. These preliminary findings suggest that genotype-based educational feedback may represent a low-intensity approach to addressing selected hazardous drinking behaviors in occupational settings, although controlled studies are needed to confirm its effectiveness.