The association between poor antiretroviral adherence and unsafe sex: differences by gender and sexual orientation and implications for scale-up of treatment as prevention.

Non-adherence to safer sex and non-adherence to ART can each have adverse health consequences for HIV-infected individuals and their sex partners, but little is known about the association of these behaviors with each other. This "dual risk" has potential negative public health consequences since non-adherence can lead to the development of resistant virus that can then be transmitted to sex partners. Among participants in the Multi-site Adherence Collaboration in HIV we examined, at study baseline, the association between the frequency of unprotected sex (assessed by self-report) and ART adherence (assessed by Medication Event Monitoring System, Aardex) among the sexually active participants in the five studies (N = 459) that collected sexual risk behavior. The bivariate association between sexual risk behaviors and ART adherence was assessed by Pearson correlations; subsequently regression analyses were used to evaluate the role of demographic characteristics, depression and substance use in explaining the "dual risk" outcome (sexual risk and non-adherence). Among participants who had been sexually active, more unprotected anal/vaginal sex was weakly associated with poorer ART adherence (r = -0.12, p = 0.01 for the overall sample). Further analysis showed this association was driven by the heterosexual men in the sample (r = -0.29, p < 0.001), and was significant only for this group, and not for gay/bisexual men or for women (heterosexual and homosexual). Neither substance use nor depression accounted for the association between sexual risk and ART adherence. HIV-infected heterosexual men who are having difficulty adhering to ART are also more likely to engage in risky sexual behaviors and therefore may benefit from counseling about these risk behaviors. We must identify procedures to screen for these risk behaviors and develop interventions, appropriately tailored to specific populations and identified risk factors, that can be integrated into routine clinical care for people living with HIV. This will become increasingly important in the context of wider access to treatment globally, including new recommendations for ART initiation earlier in a patients' disease course (e.g., "Test and Treat" paradigms).