New data from the CDC suggests young gay and bisexual men are receiving HIV diagnoses at higher rates than their older peers, but it may be due in part to increased testing.
Andrew Mitsch, MPH
New data from the Centers for Disease Control and Prevention (CDC) show that HIV diagnoses are rising faster for young men who have sex with men (MSM) than for their older MSM peers. However, the extent to which the rates are being driven by increased testing or by an increase in transmission is unclear.
The CDC reported that between 2008 and 2016, the annual number of new HIV diagnoses among young MSM (those aged 13-29) increased by 3% per year, while decreasing 4% per year among MSM aged 30 to 49, and remaining virtually unchanged for MSM over the age of 50. Overall, the number of new infections among the youngest cohort of MSM was 4 times higher than among the 50-plus age group.
At the same time, the number of MSM living with HIV from 2008-2015 increased by 11% among the 50-and-older age group, and as of the end of 2015 there were 3 times as many 50-plus MSM living with HIV as there were young men with HIV. The latter figure is evidence of the effect of antiretroviral therapy (ART), which is making it possible for people to live long lives even after an HIV diagnosis.
Andrew Mitsch, MPH, an epidemiologist with the CDC’s Division of HIV/AIDS Prevention, said the age-cohort disparities themselves were not a surprise, but he and his colleagues were struck by the size of the gaps. However, Mitsch told MD Magazine® the increase in diagnoses among young MSM might not be due to risky behavior.
“The increase in annual HIV diagnoses among younger gay and bisexual males might reflect increased HIV testing, in addition to ongoing transmission,” he said. “Our report suggests that the public health community and partners are reaching more members of this vulnerable group with HIV testing. It’s important to note, however, that some younger gay and bisexual males—like American Indian and Asian—are presenting at diagnosis with advanced immunosuppression.”
Mitsch pointed to recent research showing that incidence of undiagnosed HIV among MSM ages 13 and older dropped by 3% per year from 2008 to 2015. Among the youngest cohort in that study—MSM aged 13-24—the drop was 4% per year. Current recommendations call for young men to be tested for HIV annually.
One issue hanging over the discussion is utilization rates of PrEP, the pre-exposure prophylactic. Overall usage remains very low and varies widely by region. A letter published in the New England Journal of Medicine earlier this month highlighted some of those disparities.
“[T]hough the CDC estimates that more than 1.1 million people in the United States would benefit from PrEP, it has been prescribed to less than 150,000 people since it went on the market,” wrote Robert H. Goldstein, MD, PhD, of Massachusetts General Hospital, and colleagues. “Of these prescriptions, nearly 75% went to white gay or bisexual men, predominantly those living in the Northeast or on the West Coast.”
Mitsch agreed that access to PrEP remains an issue, but he said awareness is also a challenge.
“There is still work to do to increase knowledge of PrEP among both health care providers and a broader population of people who would benefit from its use,” he said.
The Morbidity and Mortality Weekly Report, “Age-Associated Trends in Diagnosis and Prevalence of Infection with HIV Among Men Who Have Sex with Men — United States, 2008—2016,” can be accessed on the CDC’s website.