Heterogeneity in HIV/Sexually Transmitted Infection Prevalence and Prevention Among the Partners of Transgender and Nonbinary People

Background: Transgender and nonbinary (TNB) people are diverse in their sexual orientation and partnerships. We describe the epidemiology of HIV/sexually transmitted infection (STI) prevalence and prevention utilization among the partners of TNB people in Washington State. Methods: We pooled data from five 2017 to 2021 cross-sectional HIV surveillance data sources to generate a large sample of TNB people and cisgender people who had a TNB partner in the past year. We described characteristics of recent partners of trans women, trans men, and nonbinary people and used Poisson regression to assess if having a TNB partner was associated with self-reported HIV/STIs prevalence, testing, and pre-exposure prophylaxis (PrEP) use. Results: Our analysis included 360 transwomen, 316 transmen, 963 nonbinary people, 2896 cis women, and 7540 cis men. Overall, 9% of sexual minority cismen, 13% of sexualminority ciswomen, and 36% of TNB participants reported having any TNB partners. There was significant heterogeneity in HIV/STI prevalence, testing, and PrEP use among the partners of TNB people by study participant gender and the gender of their sex partners. In regression models, having a TNB partner was associated with a higher likelihood of HIV/STI testing and PrEP use but was not associated with higher HIV prevalence. Conclusions: We observed significant heterogeneity in HIV/STI prevalence and preventative behaviors among the partners of TNB people. Given that TNB people are diverse in their sexual partnerships, there is a need to better understand individual-, dyad-, and structural-level factors that facilitate HIV/STI prevention across these diverse partnerships.