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Sexual risk trajectories among MSM in the United States: implications for pre-exposure prophylaxis delivery
Heather A Pines1, Pamina M Gorbach, Robert E Weiss
1Departments of *Epidemiology; †Biostatistics, Fielding School of Public Health, University of California, Los Angeles, CA; Departments of ‡Family Medicine; §Psychiatry and Biobehavioral Sciences, University of California, Los Angeles, CA; ‖Center for Clinical AIDS Research & Education, David Geffen School of Medicine, University of California, Los Angeles, CA; ¶David Ostrow & Associates, LLC Chicago, IL; #The Chicago MACS, Northwestern University, Evanston, IL; **Department of Behavioral and Community Health Sciences, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, PA; and ††Department of Medicine, Georgetown University Medical Center, Washington, DC.
Background:
Despite evidence supporting pre-exposure prophylaxis (PrEP) efficacy, there are concerns regarding the feasibility of widespread PrEP implementation among men who have sex with men (MSM). To inform the development of targeted PrEP delivery guidelines, sexual risk trajectories among HIV-negative MSM were characterized.
Methods:
At semiannual visits from 2003 to 2011, HIV-negative MSM (N = 419) participating in the Multicenter AIDS Cohort Study provided data on sexual risk behaviors (SRBs) since their last visit. Based on their reported behaviors, participants were assigned a SRB score at each visit as follows: 0 = no insertive or receptive anal intercourse, 1 = no unprotected insertive or receptive anal intercourse, 2 = only unprotected insertive anal intercourse, 3 = unprotected receptive anal intercourse with 1 HIV-negative partner, 4 = condom serosorting, 5 = condom seropositioning, and 6 = no seroadaptive behaviors. Group-based trajectory modeling was used to examine SRB scores (<4 vs. ≥4) and identify groups with distinct sexual risk trajectories.
Results:
Three sexual risk trajectory groups were identified: low-risk (n = 264; 63.0%), moderate-risk (n = 96; 22.9%; mean duration of consecutive high-risk intervals ∼1 year), and high-risk (n = 59; 14.1%; mean duration of consecutive high-risk intervals ∼2 years). Compared to low-risk group membership, high-risk group membership was associated with younger age (in years) [adjusted odds ratio (AOR) = 0.92, 95% confidence interval (CI): 0.88 to 0.96], being White (AOR = 3.67, 95% CI: 1.48 to 9.11), earning an income ≥$20,000 (AOR = 4.98, 95% CI: 2.13 to 11.64), distress/depression symptoms (Center for Epidemiologic Studies Depression Scale ≥ 16) (AOR = 2.36, 95% CI: 1.14 to 4.92), and substance use (AOR = 2.00, 95% CI: 1.01 to 3.97).
Conclusions:
Screening for the sociodemographic and behavioral factors described above may facilitate targeted PrEP delivery during high-risk periods among MSM.
Insights
This study identified distinct sexual risk trajectories in men who have sex with men (MSM). Targeted screening for younger age, White race, higher income, depression, and substance use can improve pre-exposure prophylaxis (PrEP) delivery.
Area of Science:
- Public Health
- Epidemiology
- Behavioral Science
Background:
- Pre-exposure prophylaxis (PrEP) is effective but implementation faces challenges.
- Understanding sexual risk behaviors is crucial for targeted HIV prevention strategies.
Purpose of the Study:
- To characterize sexual risk trajectories among HIV-negative men who have sex with men (MSM).
- To inform the development of guidelines for targeted pre-exposure prophylaxis (PrEP) delivery.
Main Methods:
- Group-based trajectory modeling analyzed sexual risk behaviors (SRBs) in 419 HIV-negative MSM from 2003-2011.
- Participants were categorized into low-risk, moderate-risk, and high-risk sexual behavior groups.
Main Results:
- Three risk groups were identified: low-risk (63.0%), moderate-risk (22.9%), and high-risk (14.1%).
- High-risk group membership was associated with younger age, White race, income ≥$20,000, depression symptoms, and substance use.
Conclusions:
- Identifying specific sociodemographic and behavioral factors aids in targeted pre-exposure prophylaxis (PrEP) delivery.
- Screening for these factors can help identify MSM during periods of elevated HIV risk.
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