Abstract and Introduction
Abstract
Background: Studies from the 1990s suggested sex with older partners was associated with HIV infection. We evaluated the hypothesized association between primary HIV infection (PHI) and having older sexual partners among men who have sex with men (MSM).
Methods: MSM with PHI and HIV-uninfected MSM completed audio computer-assisted self-interviews exploring behaviors involving their 3 most recent sexual partners before enrollment (if uninfected) or diagnosis (if PHI).
Results: Of 74 men reporting any lifetime sex with men, 20 had PHI (27%). Demographics (including age) were similar between groups; 39% were non-white and 74% identified as gay. The mean age of sex partners differed significantly: men with PHI had partners on average 6 years older than themselves, whereas uninfected men's partners were 4 months their junior (P < 0.001). After adjusting for race, sex while intoxicated, and having a serodiscordant/serostatus unknown partner, a participant had twice the odds of PHI if his sex partner was 5 years his senior (odds ratio 2.0, 95% confidence interval: 1.2 to 3.3).
Conclusions: Among a sample of young MSM, the odds of HIV infection increased significantly as the age of sexual partners increased. These findings can inform behavioral interventions in communities of at-risk MSM and secondary prevention efforts among those already living with HIV.
Introduction
The number of Americans growing older with HIV is increasing. Before the advent of combination antiretroviral therapy, half of the patients died within 10 years of their HIV diagnosis. With current antiretrovirals (ARVs), the life expectancy of a 25-year-old infected with HIV is at least another 35 years. As the size of the population living with HIV increases and the population ages, the number of opportunities for HIV transmission will increase, because of increasing net exposure through sexual contact.
The factors driving selection of sex partners are complex. In one large qualitative study of men who have sex with men (MSM), roughly half of participants cited age of a potential partner as a specific draw, alongside other physical features. Among many younger MSM, relationships with older men connote stability, emotional maturity, and mentorship. For older men living in an increasingly ageist culture, having a younger partner may provide a sense of power or virility and frame aging in a positive light. MSM seeking long-term partnerships seem to narrow their desired age range, whereas those looking for a partner for casual sex generally have less stringent requirements for partner age.
Near the peak of the domestic HIV epidemic in the 1990s, epidemiologic and modeling studies suggested that selection of older partners in sexual networks was associated with acquiring HIV infection-both among MSM and heterosexuals. This "dissortative" mixing in sexual networks (selecting partners unlike oneself) seemed to fuel HIV transmission. Given increasing trends among young MSM for unprotected anal intercourse with partners of unknown HIV serostatus and frequency of age-mixing with older sex partners among adolescents and young adults, the potential for secondary transmission of HIV from older MSM to younger ones requires reexamination. Among those younger than 25 years old diagnosed with HIV in the state in 2007, 63% were MSM. We performed the present study to determine if having an older sexual partner was a risk factor for acquisition of HIV among MSM in NC.