Unique HIV Risk Factors and Prevention Needs for Transgender Women and Cisgender Men Who Have Sex with Men in Bangkok, Thailand

Abstract

Background: Transgender women (TGW) and cisgender men who have sex with men (cis-MSM) are often grouped together as key populations. We evaluated behavioral and other characteristics that may distinguish TGW from cis-MSM in Bangkok, Thailand.

Methods: We enrolled into an 18-month cohort cis-MSM and TGW 18-35 years of age without HIV, who reported anal intercourse plus condomless anal intercourse, multiple partners, transactional sex, and/or sexually transmitted infection. Robust multivariable Poisson regression was used to estimate adjusted prevalence ratios (aPRs) and confidence intervals (95% CIs) for associations with being a TGW. Among TGW, logistic regression with generalized estimating equations was used to estimate adjusted odds ratios (aORs) and 95% CIs for associations with taking hormones and having undergone gender affirmation surgery (GAS).

Results: From 2017 to 2019, 660 cis-MSM and 348 TGW were enrolled. Compared to cis-MSM, TGW were more likely to be attracted to mostly/only men (aPR: 3.79, 95% CI: 1.57-9.13), have a higher monthly income (aPR: 1.25, 95% CI: 1.04-1.50), have lived in their current residence for <1 year (aPR: 1.21, 95% CI: 1.01-1.46), have engaged in sex work (aPR: 1.48, 95% CI: 1.23-1.77), and be less likely to have ever undergone HIV testing (aPR: 0.83, 95% CI: 0.70-0.98). Among TGW, 149 (42.8%) were taking hormones and 33 (9.5%) had undergone GAS. GAS was more common among TGW who ever used methamphetamines (aOR: 1.55, 95% CI: 1.00-2.41) and those >23 years (18-20-year olds aOR: 0.17, 95% CI: 0.05-0.55; 21-23-year olds aOR: 0.36, 95% CI: 0.20-0.65).

Conclusions: TGW and cis-MSM are unique populations; tailored, gender-affirming, differentiated models of HIV prevention and care are necessary to address vulnerabilities specific to each key population.

Keywords: HIV; Thailand; sexual and gender minorities; transgender persons.

FIG. 1.

Sexual behaviors of cisgender MSM and TGW enrolled in an HIV incidence study at two clinics in Bangkok, Thailand. (A) Comparison between TGW and cisgender MSM. (B) Among TGW, sexual behavior by hormone use. (C) Among TGW, sexual behavior by gender affirmation surgery status. Only statistically significant comparisons (p<0.05) are shown. GAS, gender affirmation surgery; MSM, men who have sex with men; TGW, transgender women.

FIG. 2.

Condom use during anal sex by cisgender MSM and TGW enrolled in an HIV incidence study at two clinics in Bangkok, Thailand. (A) Comparison between TGW and cisgender MSM. (B) Among TGW, condom use by hormone use. (C) Among TGW, condom use by gender affirmation surgery status. Only statistically significant comparisons (p<0.05) are shown.