Correlates of unprotected vaginal or anal intercourse with women among substance-using men who have sex with men.

The role men who have sex with men and women (MSMW) play in heterosexual HIV transmission is not well understood. We analyzed baseline data from Project MIX, a behavioral intervention study of substance-using men who have sex with men (MSM), and identified correlates of unprotected vaginal intercourse, anal intercourse, or both with women (UVAI). Approximately 10 % (n = 194) of the men reported vaginal sex, anal sex, or both with a woman; of these substance-using MSMW, 66 % (129) reported UVAI. Among substance-using MSMW, multivariate analyses found unemployment relative to full/part-time employment (OR = 2.28; 95 % CI 1.01, 5.17), having a primary female partner relative to no primary female partner (OR = 3.44; CI 1.4, 8.46), and higher levels of treatment optimism (OR = 1.73; 95 % CI 1.18, 2.54) increased odds of UVAI. Strong feelings of connection to a same-race gay community (OR = 0.71; 95 % CI 0.56, 0.91) and Viagra use (OR = 0.31; 95 % CI 0.10, 0.95) decreased odds of UVAI. This work suggests that although the proportion of substance-using MSM who also have sex with women is low, these men engage in unprotected sex with women, particularly with primary female partners. This work highlights the need for further research with the substance using MSMW population to inform HIV prevention interventions specifically for MSMW.