Condomless anal intercourse among males and females at high risk for heterosexual HIV infection

Background: Understanding and addressing heterosexual HIV transmission requires attention to the range and context of heterosexual sexual behaviors. We sought to determine population-based prevalence of condomless anal intercourse (CAI) among individuals at increased heterosexual HIV risk in Baltimore and to identify demographic, behavioral, and health-related correlates. Methods: Data were from a cross-sectional study of 185 males and 198 females at increased heterosexual risk for HIV recruited using respondent-driven sampling as part of Centers for Disease Control and Prevention's National HIV Behavioral Surveillance Project in Baltimore, August-December 2010. Bivariate and multivariate logistic regression examined factors associated with heterosexual CAI. Results: The sample was majority African American, with a mean age of 38 years among men and 34 years among women. Forty-two percent of men (95% confidence interval, 30.9%-52.0%) and 38% of women (95% confidence interval, 29.4%-47.2%) reported any CAI in the past year, with variance by partner type and sex. Among men, CAI was significantly associated with homelessness, casual and exchange partners, same-sex partner in past year, and substance use. Among women, CAI was significantly associated with lower education, casual and exchange partners, same-sex partner in past year, multiple partners, and substance use. In adjusted sex-specific models, males and females with increasing numbers of partners were more likely to engage in CAI. Conclusions: It is important to recognize the efficiency of transmission of HIV and other sexually transmitted infections through CAI. There is a need to broaden heterosexual sexual health promotion and HIV/sexually transmitted infection prevention to adequately and appropriately address risks and prevention strategies for anal intercourse.