Purpose: National studies examining alcohol and other drug use by sexual orientation have been primarily cross-sectional. Understanding changes in sexual orientation over time may further elucidate the mechanisms behind sexual orientation differences in alcohol and other drug use. This national longitudinal study examines changes in sexual orientation across four waves (2013-2019), and the associations with symptomatic alcohol and other drug use.

Methods: Data from Waves 1 through 5 of the Population Assessment of Tobacco and Health (PATH) study were used to examine associations of sexual identity change/stability and sexual identity-attraction discordance/concordance from baseline to follow-up with symptomatic substance use at follow-up. We examined four outcomes: any symptomatic substance use, symptomatic alcohol use, symptomatic other drug use, and symptomatic alcohol + other drug use. Mixed effects logistic regression models were used and all analyses were weighted and stratified by sex.

Results: In models adjusting for potential confounders, greater likelihood of symptomatic alcohol and other drug use outcomes was found among males and females experiencing a change from a heterosexual to sexual minority identity and among females with new or consistent sexual identity-attraction discordance.

Conclusion: These findings highlight important sex differences and suggest that the period of transitioning to a sexual minority identity is a particularly vulnerable period for symptomatic alcohol and other drug use. For females, incongruent sexual identity and attraction is also a risk factor. Interventions that assist individuals during this transitional period and during a time when identity and attraction are incongruent, may reduce symptomatic substance use during this period.