Differences in how spouses influence each other's alcohol use in same- and different-sex marriages: A daily diary study.

Rationale: Different-sex spouses influence each other's alcohol consumption, with women having more influence on their spouses than men. Because women drink less than men, this long-term influence partly explains why married men and women consume less alcohol than their unmarried peers. However, much less is known about possible gender differences in the ways spouses influence each other's alcohol use on a day-to-day basis in same-compared to different-sex marriages. Because sexual minority people are at higher risk for alcohol use disorders compared to their heterosexual counterparts, such knowledge could shed light on ways to reduce this risk and alcohol use disparities between sexual minority and heterosexual people.

Method: We use 10 days of diary data collected in 2014-2015 in the United States from 157 female same-sex, 106 male same-sex, and 115 different-sex married couples in midlife (ages 35-65) to examine how one spouse's drinking influences how much the other spouse drinks on the following day.

Results: Men reported higher levels of daily drinking than women; after including covariates, men in different-sex marriages reported drinking at the highest levels. Results from actor-partner interdependence models show that men in same- and different-sex marriages drink more, and women in different-sex marriages drink less when their spouse drinks more the previous day. Female same-sex spouses did not change their drinking behaviors in response to their spouse's drinking.

Conclusions: Overall higher rates of drinking among men in same-sex marriages suggest an accumulation effect of drinking that may contribute to sexual minority health disparities. Women and men in different-sex marriages may be engaging in social control or navigating masculinity norms. Women in same-sex marriages may not feel the need to adjust to low levels of drinking by their spouses. Findings suggest that spousal influence over alcohol consumption unfolds differently in same-sex compared to different-sex marriages.