Young black men who have sex with men (MSM) are 16 times more likely to have an HIV infection than their white peers despite more frequent testing for HIV and being less likely to have unsafe sex, reports a new Northwestern Medicine study.
The study was recently published in the Journal of Acquired Immunodeficiency Syndromes.
If these rates persist, one out of every two black MSM will become infected with HIV at some point in their lives, compared to one in five Hispanic MSM and one in 11 white MSM, reports the Centers for Disease Control and Prevention.
"We have known from prior studies that this paradox exists -- black young MSM engage in fewer risk behaviors but have a much higher rate of HIV diagnosis," said senior study author Brian Mustanski, professor of medical social sciences at Northwestern University Feinberg School of Medicine and director of the Northwestern Institute for Sexual and Gender Minority Health and Wellbeing. "Our study illuminates how HIV disparities emerge from complex social and sexual networks and inequalities in access to medical care for those who are HIV positive."
"Their social and sexual networks are more dense and interconnected, which from an infectious disease standpoint makes infections transmitted more efficiently through the group," Mustanski said. "That, coupled with the higher HIV prevalence in the population, means any sexual act has a higher chance of HIV transmission."
The study is the largest and most comprehensive to assess why these disparities exist. It analyzed young black MSM's social networks, such as past sexual partners, as well as measures of stress, past trauma and stigma. The authors used data from RADAR, a project funded by the National Institute on Drug Abuse, that identifies drivers of HIV infections on multiple levels, including sexual partner and relationship characteristics, network dynamics and community-level factors. The study collected data from 1,015 MSM between the ages of 16 and 29 living in the Chicago metropolitan area.
Among the study's key findings about racial disparities in HIV infection:
- Black MSM reported the lowest number of sexual partners overall.
- Black MSM tested for HIV more frequently but were more likely to have a detectable HIV viral load if HIV positive.
- Black MSM were more likely to report not having close relationships with their sexual partners.
- Black MSM were more likely to report hazardous marijuana use, while white MSM were more likely to report high levels of alcohol problems.
- Black MSM experienced greater levels of stigma, victimization, trauma and childhood sexual abuse.
The study's findings suggest current HIV prevention efforts are effective in reducing risky sexual behaviors and promoting awareness about the importance of HIV testing among black MSM.
"Overall, young black MSM do not report higher rates of HIV risk behaviors like condomless sex," said Ethan Morgan, a postdoctoral fellow at Northwestern's Institute of Sexual and Gender Minority Health and Wellbeing and a co-author on the study. "But aspects of their social networks align with increased HIV risk. By learning more about young black MSM's social networks, we can better understand what drives such persistent racial disparities in HIV -- and close that gap."
Other Northwestern authors include Richard D'Aquila, Michelle Birkett, Patrick Janulis and Michael Newcomb.
The study was supported by grant U01DA036939 from the National Institute on Drug Abuse of the National Institutes of Health.
Source: Northwestern Medicine