Gay and bisexual men enrolled in the Multicenter AIDS Cohort Study (MACS) who reported sexual abuse and social shaming in childhood experience psychosocial health problems later in life known to substantially increase the risk of HIV infection, according to data reported Wednesday, July 21, at the XVIII International AIDS Conference in Vienna.

The elaborate study, presented in Vienna by Sin How Lim, PhD, of the University of Pittsburgh and her colleagues, included 1,086 HIV-positive and -negative gay and bisexual men enrolled in the MACS, which was started in 1983 and remains the longest-running National Institutes of Health–funded investigation of HIV/AIDS.

The aim of the study was to explore “syndemic” outcomes in the MACS patients, a relatively new epidemiological term referring to the concentration of two or more health conditions that interact synergistically to contribute to excess disease in a population. The term was actually coined back in 1992, when a medical anthropologist named Merrill Singer, PhD, attempted to describe the inextricable and mutually reinforcing connections between health problems—such as substance abuse and domestic violence—and HIV among urban women in the United States.

In the MACS study, Lim's team found that almost 10 percent of the volunteers reported that they had been victims of childhood sexual abuse and nearly 30 percent had experienced gay-related victimization between the ages of 12 and 14, including verbal insults, bullying, threats of physical violence and physical assaults.

MACS volunteers who experienced childhood sexual abuse and a sense of “masculinity failure” were more likely to engage in substance use, experience depression and sexual compulsivity and to be involved in intimate partner violence—all known to be independent risk factors for unprotected anal sex and, ultimately, HIV infection. This finding, Lim reported, confirmed the occurence of syndemic outcomes in this particular population of men. 

“Our study shows that the early socialization experiences of gay men can be deeply stigmatizing and increase their risks for these syndemic conditions in adulthood,” Lim said. “Given the long-lasting impacts, effective interventions should address multiple interrelated social issues early on rather than focusing on each problem in isolation.”