Author: Mark Mascolini
07 November 2009
Risk of becoming infected with HIV was almost 90% lower in circumcised Australian men who have sex with men (MSM) who practice insertive rather than receptive anal sex. That finding comes from a prospective cohort study, not from a randomized trial, so factors not considered in the analysis may also influence HIV risk.
The Health in Men (HIM) cohort recruited 1426 HIV-negative men in Sydney, Australia from 2001 through 2004 and studied them through mid-2007. Men had an HIV test every year and gave detailed information on sexual risk behavior every 6 months.
Over the course of the study, 53 men became infected with HIV for an incidence of 0.78 per 100 person-years. Statistical analysis that factored in behavioral risk factors determined that circumcision did not significantly lower the overall risk of HIV infection (hazard ratio [HR] 0.78, 95% confidence interval [CI] 0.42 to 1.45, P = 0.424).
One third of study participants reported a preference for insertive (rather than receptive) anal intercourse. In that group, statistical analysis that factored in age and unprotected anal intercourse determined that circumcision lowered the risk of HIV infection nearly 90% (HR 0.11, 95% CI 0.03 to 0.80, P = 0.041).
The researchers conclude that “circumcision may have a role as an HIV prevention intervention in this subset of homosexual men.”
Three randomized trials in sub-Saharan Africa found that circumcision lowers the risk of HIV acquisition 50% or more in heterosexual men.
Source: David J. Templeton, Fengyi Jin, Limin Mao, Garrett P. Prestage, Basil Donovan, John Imrie, Susan Kippax, John M. Kaldor, Andrew E. Grulich. Circumcision and risk of HIV infection in Australian homosexual men. AIDS. 2009;23:2347-2351.
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