MSM Found to Underestimate Risk of HIV Infection, Hindering Uptake of PrEP

Although researchers continue to make great strides in the fight against HIV, there are still many obstacles to overcome in terms of prevention. One such obstacle is accurate HIV risk perception among men who have sex with men (MSM), a population that accounts for 70% of new HIV infections in the United States.

In an oral abstract session at the 25th Conference for Retroviruses and Opportunistic Infections (CROI) held in Boston, Massachusetts, Jill Blumenthal, MD, associate clinical professor at the University of California, San Diego School of Medicine, discussed how inaccurate HIV risk perception by MSM remains an obstacle to prevention, despite greater access to pre-exposure prophylaxis (PrEP).

To address this issue, Dr. Blumenthal and her team studied whether or not providing information on their risk of contracting HIV to MSM would increase their uptake of PrEP. The team tested this hypothesis in a randomized controlled trial dubbed, PrEP Accessibility Research and Evaluation 2, or PrEPARE2, which enrolled 171 MSM participants, all recruited from HIV testing sites.

For the study, participants were given a baseline survey which collected information such as demographics, risk behaviors, and the participant’s perception of their risk of contracting HIV. The results of the survey generated 2 risk scores: a self-perceived risk (SPR) score, which was based on 3 risk perception questions, and an HIV risk score (CalcR) which would calculate an individual’s estimated 1-year risk of becoming infected with HIV compared with the average risk among MSM. The CalcR score was “based on reported condomless anal sex acts, sexually transmitted infections (STIs), and needle-sharing events,” according to the study abstract. Participants were categorized as either low, medium, high, or very high risk for HIV, based on these scores.

Participants were then randomly assigned to 1 of 2 study arms: 86 were assigned to the intervention arm, where they were provided with their CalcR risk score; 85 were assigned to the control arm, where they received standard counseling on reducing their risk of HIV infection only.

Of the 171 participants, 81% stated that they had heard of PrEP and more than half (57%) professed feeling like they would be good candidates for PrEP. As a whole, participants reported a median of 5 sexual partners within the past 6 months.

After 8 weeks, the investigators contacted participants in each group to see if they had started PrEP or if they felt they were good candidates for the medication. The results revealed that a total of 14 participants had begun PrEP, out of a total of 135 participants who were contacted (59 from the control arm and 76 from the intervention arm).

Why didn’t more participants initiate PrEP?

The investigators found that 36% of the participants had low risk perception; 18% did not want to take pills; and 13% said that they were waiting for a PrEP visit. Additionally, further analysis revealed that participants’ SPR score did not line up with the CalcR score; more than one-third of the study participants underestimated their risk of HIV infection.

“In this cohort of at-risk MSM, providing an objective HIV risk score alone did not increase PrEP uptake, perhaps due to discordance between self-perceived and actual HIV risk,” the study authors wrote. “Further, many participants did not think their risk was high enough to use PrEP.”

Based on the results of this study, Dr. Blumenthal and her team concluded that the time to correct misperceptions about the actual risk of HIV infection should come when patients are being tested for HIV. Furthermore, PrEP should be initiated that same day in those patients who are at risk in order to improve uptake of the medication.