Incident HIV Infection Among Young Men Associated With Female Sexual Partner Types Identified Through Latent Class Analysis, Rakai, Uganda.

Background: Sexual partner characteristics are important determinants of HIV acquisition, but little is known about partner types of young men in sub-Saharan Africa.

Methods: Sexually active men aged 15-24 years from 5 rounds (2005-2013) of the Rakai Community Cohort Study in Uganda reported characteristics of up to 4 past-year female partners. Partner types were identified using latent class analysis. HIV incidence rates (IRs) were calculated by partner-type combinations, and individual-level risk adjusted IR ratios (aIRRs) relative to the lowest incidence type were estimated using the Poisson regression with generalized estimating equations.

Results: Young men (N = 1771) reported 4539 past-year female sexual partners. Three partner types were identified: type A: noncohabiting, student, medium duration partnerships; type B: cohabiting, nonstudent, longer duration partnerships; and type C: noncohabiting, nonstudent shorter duration partnerships. Type C partners engaged in the most HIV-related risk behaviors. Many men (29%) had more than 1 partner type/round. IR overall was 9.8/1000 person-years [95% confidence interval (CI): 4.7 to 20.6]. IR was 4.0 (95% CI: 1.2 to 12.7) for men with type A partners alone (41% of men). Relative to them, IR for those with type B partners alone (25%) was not significantly different. Men with type C partners alone (5%) had higher risk (aIRR = 3.2; 95% CI: 1.0 to 9.9), as did men with >1 partner type, including men with both type A and type B partners (12%; aIRR = 6.3; 95% CI: 2.5 to 15.9) and men with type C and other partner types (17%; aIRR = 4.3; 95% CI: 1.7 to 10.8).

Conclusions: Partner-type combination was strongly associated with HIV incidence; type C partners and having more than 1 partner type were the riskiest patterns.