WASHINGTON – The rate of new HIV infections among black men who have sex with men was 2.8% per year, nearly 50% higher than the rate seen in white men who have sex with men in the United States, a longitudinal cohort study conducted in six U.S. cities has found.

"Culturally tailored interventions that encourage repeated HIV/[sexually transmitted infection] testing [and] engagement with treatment/prevention, and that address social factors such as poverty, are urgently needed" for black men who have sex with men (MSM), said Beryl Koblin, Ph.D., an epidemiologist at the school of public health at Columbia University, New York.

The findings come from a study conducted within the HIV Prevention Trials Network (HPTN). The study, HPTN 061, is the largest cohort of prospectively followed black MSM in the United States. Funded by the National Institutes of Health, HPTN 061 is designed to determine the feasibility and acceptability of a multicomponent intervention for black MSM, including peer health programs. These incidence data are among the early findings from the study, Dr. Koblin said.

The study was conducted in Atlanta, Boston, Los Angeles, New York, San Francisco, and Washington between July 2009 and October 2010. Black MSM were recruited from the community or referred by sexual partners. Eligibility criteria were men who identified as men or were male at birth; were identified as black, African American, Caribbean, African, or multiethnic black; were at least 18 years old; and had had at least one episode of unprotected anal intercourse with a man in the past 6 months.

The men completed questionnaires regarding their social and sexual networks and were tested for gonorrhea, chlamydia, and syphilis. They received risk-reduction counseling and offers of services from a peer community navigator to link to clinical and social services. Those who tested positive for any infection were guided to medical care services. Participants were offered incentives to refer up to five black sexual partners for participation in the study.

A total of 1,553 black MSM enrolled, of whom 1,379 (89%) reported no prior HIV diagnosis. Of the 96% who agreed to HIV testing, 12% (165) were newly diagnosed as HIV positive, including 3 men with acute HIV infection. Among the 1,168 men who were uninfected at baseline, a little over a third were aged 30 years or younger; fewer than half had a college education or more. Fewer than a third worked full or part time, and two-thirds had an annual income of less than $20,000. About 14% had a sexually transmitted infection (STI) at the time of enrollment, Dr. Koblin said at a press briefing.

After 1 year of follow-up, among the 1,009 who had at least one follow-up test at 6 months or 1 year, the overall incidence of new HIV infection was 2.8%. Men aged 18-30 years and younger had a significantly higher HIV incidence than did those who were older (5.9% vs. 1.0%).

Among men aged 30 and younger, the incidence of new HIV infections among black MSM was three times the rate seen in white MSM of the same age, Dr. Koblin said.

Men who reported having unprotected anal intercourse had an annual HIV incidence rate of 5%, and the annual incidence rate among those with an STI at baseline was 6%. For those who reported having male partners only, the annual incidence rate was 4%. For men identifying as exclusively gay/homosexual, the incidence was 5%, compared with just 1.5% for those who identified as bisexual.

Compared with the 1,168 HIV-negative men, the 174 who reported a prior HIV diagnosis and the 165 who were newly diagnosed were more likely to be unemployed (82% for both HIV-positive groups vs. 65% for those who were HIV negative), to have household incomes less than $50,000 per year (94% vs. 87%), to have a homosexual or gay identity (69% of those previously diagnosed and 58% of the newly diagnosed vs. 47% of those who were HIV negative), and to have had unprotected receptive anal intercourse (55%, 57%, and 43%, respectively.

The HIV-negative men were more likely to have had a female partner in the past 6 months (49% vs. 25% of those previously diagnosed and 35% of the newly diagnosed). Other STIs were twice as common among both HIV-positive groups (25% and 27%, respectively), compared with 13% among the HIV-negative subjects.

"These data are important in terms of identifying [at risk] subpopulations," she said, adding that particular focus should be paid to young men, those reporting receptive anal sex at baseline, those reporting exclusively male partners and who are gay identified, and those who had an STI diagnosed at baseline.

Dr. Koblin stated that she had no financial disclosures.

HIV Incidence Higher in Young Black MSM Community