BACKGROUND: Alcohol use disorder (AUD) among older adults, particularly with respect to gender differences in treatment outcomes, remains underexplored. Our objective was to explore gender differences in AUD treatment outcomes among older adults, focusing on continuous measures (e.g., drinks per day) and binary measures (e.g., abstinence) across a 1-year period.

METHODS: We analyzed data from a multinational randomized controlled trial involving 693 older adults (60+) diagnosed with DSM-5 AUD. Participants received motivational enhancement therapy and the community reinforcement approach, across sites in Denmark, Germany, and the United States. Participants were assessed at baseline and after 4, 12, 26, and 52 weeks. Multilevel mixed-effects linear and logistic regressions were used, adjusted for sociodemographic and baseline drinking characteristics.

RESULTS: Both men and women showed significant improvements across all outcomes. At baseline, females reported 0.75 fewer drinks/day, 1.33 fewer drinks/drinking day, and 50% lower odds of low blood alcohol content (BAC) compared to males (OR = 0.50; p < 0.05). Gender-time interactions showed smaller reductions in females' drinks per day and drinks per drinking day (p < 0.05), resulting in similar drinking levels at follow-ups. No gender differences were found at any time points for percent days abstinent and percent heavy drinking days (p ≥ 0.05). A significant gender-time interaction was found for percent days abstinent (p = 0.04), but no consistent direction was observed across time points. For abstinence and no heavy drinking, no gender differences were found (p ≥ 0.05). No interactions between gender and time were found for any binary outcome (p ≥ 0.05).

CONCLUSIONS: Among older adults with DSM-5 AUD diagnosis, treatment led to substantial and sustained improvements across genders. While women showed less favorable drinking reductions, adjusted estimates were broadly comparable. Given women's increased physiological vulnerability to alcohol, this may not imply equivalent clinical risk. Still, findings support the potential for meaningful treatment benefits regardless of gender.