Association between relationship characteristics and willingness to use PrEP among same-sex male couples: a cross-sectional actor-partner analysis in Guangzhou, China.

The association between relationship characteristics and pre-exposure prophylaxis (PrEP) acceptability among same-sex male couples has been limitedly examined. Dyadic survey data of 139 concordant HIV-negative same-sex male couples in Guangzhou, China were collected. The willingness to use PrEP was measured assuming that the participant's partner was HIV-positive. The actor-partner interdependence model was used to examine how one's relationship characteristics affected the PrEP willingness of the subject and his partner. Most participants (79.5%) were willing to use PrEP. The two individuals of the couple were distinguished by sex role in relationship, namely one usually playing the insertive role and the other usually playing the receptive role in anal intercourse. The former was labeled as "top" and the latter labeled as "bottom". The PrEP willingness of the top partner increased when he would think his partner is having sex with other people if the partner requests condom use in relationship (AOR: 5.74, 95% CI: 1.10-29.87), and decreased when his partner would get violent upon condom use requests in relationship (AOR: 0.19, 95% CI: 0.04-0.88). The PrEP willingness of the bottom partner increased when he trusted his partner (AOR: 1.13, 95% CI: 1.02-1.25) and when he or his partner disclosed the relationship to parents (AOR: 10.57, 95% CI: 1.91-58.61). Considering the sex role and relationship characteristics in couple-based interventions are important to optimize PrEP uptake among HIV-discordant same-sex male couples.