Male circumcision and risk of HIV acquisition among MSM

Abstract

Objectives: To assess the association between male circumcision, insertive anal sex practices, and HIV acquisition in a cohort of MSM.

Methods: Data were from 1824 HSV-2-seropositive, HIV-seronegative MSM, 1362 (75%) from Peru and 462 (25%) from the US, who participated in a randomized placebo-controlled trial of HSV-2 suppression for HIV prevention (HPTN 039). Circumcision status was determined by examination at enrollment. HIV testing was done every 3 months for up to 18 months. Partner-specific sexual behavior for up to the last three partners during the previous 3 months was analyzed.

Results: There was no significant association between male circumcision and HIV acquisition in univariate analysis [relative risk (RR) = 0.84, 95% confidence interval (CI) 0.50-1.42]. In a prespecified multivariate analysis that assumed a linear relationship between the proportion of insertive acts and effect of circumcision on HIV acquisition, the interaction between circumcision and proportion of insertive acts was not significant (P = 0.11). In an exploratory analysis that categorized behavior with recent partners by proportion of insertive acts (<60 or ≥60% insertive acts), circumcision was associated with a nonstatistically significant 69% reduction in the risk of HIV acquisition (RR = 0.31, 95% CI 0.06-1.51) among men who reported at least 60% of insertive acts with recent male partners.

Conclusion: Circumcision does not have a significant protective effect against HIV acquisition among MSM from Peru and US, although there may be reduced risk for men who are primarily insertive with their male partners. This association needs to be investigated across diverse cohorts of MSM.

Figures

Fig. 1. Multivariate relative risk of HIV acquisition for circumcised versus uncircumcised men under two modeled conditions

1) The solid line depicts the predicted relative risk in a model in which the proportion of sex acts that were insertive was considered as a continuous variable (i.e., assuming a linear relationship for the proportion of acts insertive). 2) The individual point estimates (with 95% confidence interval whiskers) are from a multivariate model in which the proportion of acts that were insertive was considered as five categories: 1–20%, 21–40%, 41–60%, 61–80% and 81–100%. For both models, the proportion of sex acts that were insertive was considered as a time-dependent measure. Both multivariate models were adjusted for age, education, genital ulcer disease during follow-up, alcohol or drug use with sex, giving or receiving drugs money and/or gifts for sex, total number of sex acts, total number of described partners and having sex with a known HIV positive individual and were stratified by study site.