U.S. black gay, bisexual men have much higher HIV infection rates

By Holly Korschun | Woodruff Health Sciences Center | July 24, 2012

Speaking on this study is Paula Frew, PhD, Emory assistant professor of Medicine and study co-Investigator.

Tags »

Study results released today at the XIX International Conference on AIDS by the HIV Prevention Trials Network (HPTN) show greatly elevated rates of new HIV infections occurring among black gay and bisexual men in the U.S. (also known as men who have sex with men, or MSM), particularly young black MSM. The study, called HPTN 061 or the "Brothers" study, found that the overall rate of new HIV infections among black MSM in the six cities participating in this study was 2.3 percent per year, a rate that is nearly 50 percent higher than in white MSM in the U.S. Separate estimates of HIV incidence among black MSM by city are not yet available from the Brothers study.

Even more concerning, HPTN 061 found that young black MSM—those 30 years of age and younger—acquired HIV infection at a rate of 5.9 percent per year, three times the rate among U.S. white MSM. The overall infection rate among black MSM in this U.S. study is comparable to the rate seen in the general populations of countries in sub-Saharan Africa hardest hit by the HIV epidemic.

HPTN 061 enrolled a total of 1,553 MSM in six U.S. cities; Atlanta, Boston, New York, Los Angeles, San Francisco, and Washington, D.C. and was conducted between 2009-2011. It is the first study to determine the rate of new HIV infection among such a large prospective cohort of U.S. black MSM (referred to as HIV incidence). 

The Principal investigator at Emory for HPTN 061 is Carlos del Rio, Hubert professor and chair of the Hubert Department of Global Health at Emory's Rollins School of Public Health and professor of medicine. The Emory University site recruited 292 black men for the study or 19 percent of the total study sample, making it the No. 1 enrolling site in the country. 

"We are so grateful for the involvement of our community partners, AID Atlanta, National AIDS Education and Services for Minorities (NAESM), SomeoneCares, and Stand, Inc., for the support and guidance they offered us in preparation for the study as well as with recruitment and retention of participants," says del Rio.

"Based on these findings, tailored HIV prevention interventions for black MSM should be implemented in the US. The recent approval by the FDA of tenofovir/emtricitabine (commonly known as Truvada) for pre-exposure prophylaxis offers another tool that should help in HIV prevention, but the study showed that social determinants of disease such as poverty, homophobia and racism also play a role in the high rates of HIV among black MSM."

Additional early analyses show association between HIV infection and poverty

The HIV incidence results from HPTN 061, presented today at the XIX International AIDS Conference in Washington, D.C., are among the first findings to come out of the study. Other early analyses show that HIV infection in this study population was associated with very high rates of untreated sexually transmitted infections and with poverty. Of the self-reported HIV-negative or unknown HIV status study participants who agreed to be tested at time of enrollment, 12 percent were HIV-positive. This finding suggests low rates of HIV testing or delays in testing among black MSM.

All HIV-infected study participants were referred for HIV care and treatment services. During the study, all participants were offered the chance to work with "peer health navigators" to provide support and to assist them with access to needed services. In addition, they were provided with condoms, testing and referral treatment of sexually transmitted infections, risk reduction counseling and other standard HIV prevention services.

Paula Frew, PhD, Emory assistant professor of Medicine and study co-Investigator says, "The commitment, professionalism and responsiveness of our partners enabled us to enroll the highest number of participants compared to other cities. For this we are enormously grateful."

The success of HPTN 061 in recruiting and retaining black MSM in a year-long study, including 97 percent uptake of HIV testing, answered a primary objective of the study, and paves the way for the conduct of future HIV prevention research.

"As a member of the community, I believe that this study affirmed what we already knew was going on anecdotally and offers scientific justification for intensified resources and interventions to impact the epidemic among black MSM," says Craig Washington, AIDS advocate at AID Atlanta. "This study provides much-needed evidence on Atlanta and the nation's urgent need to bring this epidemic under control, through housing, jobs, and targeted behavioral and biomedical interventions that black MSM find relevant and important in their daily lives."

Further analysis of data from the study is ongoing to assess how HIV risk among black MSM might be affected by childhood experiences, social and sexual networks, discrimination, homophobia, incarceration and barriers to health care. These findings will help inform future research and prevention efforts.

The study is funded by the National Institute of Allergy and Infectious Diseases (NIAID), the National Institute on Drug Abuse (NIDA) and the National Institute of Mental Health (NIMH).

InvolveMENt Study: Black and White MSM Have Equal Behaviors But Unequal Risks for HIV Infection

In another Emory University study that included both black and white MSM living in Atlanta, an even higher rate of HIV infection was observed: an HIV interim incidence of 6.4 percent among Atlanta black MSM was reported today.  Findings from this study, which is ongoing, also shed light on a possibly important reason for the higher observed HIV incidence in black MSM: in the InvolveMENt study, researchers found that even with comparable sexual risk behaviors, HIV-negative black MSM were more than twice as likely to encounter a partner who might transmit HIV to them.

Researchers devised a measure of how many black and white men in the study were both HIV-infected and had enough virus in their system to pass it on to others. Using this measure and reported sexual behavior patterns, they developed a computer model to analyze results in 709 men recruited to the study thus far.

The study is being presented today along with the HPTN 061 study at the International AIDS Conference by researchers at Emory's Rollins School of Public Health. First and presenting author is Eli S. Rosenberg, associate director of research projects in epidemiology, and the study was led by Patrick S. Sullivan, associate professor of epidemiology.

"Differences in individual risk behavior don't explain the large disparities in HIV prevalence and incidence between black and white MSM," says Rosenberg. "Because black men's risk seems to be driven by the higher transmission potential of their partners, behavior change strategies won't be enough to reduce infection rates. Our results suggest the need of a broader approach that includes increasing HIV testing, linkage to health care and antiretroviral treatment of all HIV-positive MSM to reduce the risk of HIV transmission from sex partners."

The InvolveMENt study is funded by the National Institute of Mental Health (NIMH) of the National Institutes of Health.