Does Circumcision Lower the Risk of HIV Transmission for Gay and Bisexual Men?

Two recent studies produced contradictory answers to the question of whether circumcision might help prevent HIV transmission among men who have sex with men (MSM), as has been shown for heterosexual men in high prevalence countries. Conflicting data fuel the ongoing debate about whether public health officials should recommend routine circumcision for infants or at-risk adults.

Large randomized trials in African countries with a high HIV prevalence rate have shown that adult male circumcision significantly reduced the risk of acquiring HIV, and possibly other sexually transmitted infections (STIs).

As previously reported, trials in which young heterosexual men interested in circumcision were randomly assigned to receive the procedure either immediately or after a waiting period demonstrated that circumcision reduced men's odds of HIV infection by about 60%.

Studies comparing HIV infection rates between circumcised and uncircumcised men in industrialized countries with low population prevalence, however, have generally not shown that circumcision offers protection.

Furthermore, since controlled trials have looked at heterosexual men engaging in vaginal intercourse, it is unclear whether circumcision would offer a similar benefit for MSM engaging in anal sex. Two recent studies that addressed this issue produced conflicting findings.

Soweto Men's Study

Investigators with the Soweto Men’s Study compared HIV rates among 378 men who have sex with men; 88% also reported sex with women. About one-third were circumcised.

The study setting was a South African township with a population prevalence of 13%, similar to the cohorts in the aforementioned controlled circumcision trials. This study, however, was not randomized, instead comparing infection rates in men who happened to be, or not be, circumcised.

Among men who reported engaging exclusively in insertive anal intercourse with male partners, uncircumcised men had about a 4.5 times higher risk of HIV infection compared with circumcised men.




"Circumcision may be effective at reducing HIV transmission between men in high prevalence settings such as Soweto where MSM practice a high degree of sexual role segregation," the researchers concluded.

U.S. Study

The second study, presented at the National HIV Prevention Conference in Atlanta in August, looked at gay and bisexual men in the U.S., which has a low overall HIV prevalence and lower rates of STIs compared with developing countries in Africa.

Peter Kilmarx, director of the Centers for Disease Control and Prevention (CDC) Division of HIV/AIDS Prevention, and colleagues evaluated data from nearly 4900 men who reported anal sex with an HIV positive partner. They found that the overall odds of becoming infected were about 3.5%, but the risk did not differ significantly according to circumcision status.

Policy Implications

The World Health Organization and UNAIDS recommend circumcision as part of a comprehensive prevention program in developing countries with a high HIV prevalence. But is routine circumcision warranted in the U.S.?

Today, about 60% of American boys undergo circumcision as infants. This figure was about 85% in the mid-1960s, but the procedure fell out of favor for a variety of cultural and economic reasons (i.e., some insurers will not cover a procedure considered medically unnecessary). The American Academy of Pediatrics currently does not recommend infant circumcision, but is in the process of revising its policy.

The CDC is currently considering whether to recommend routine infant circumcision, and perhaps adult circumcision for at-risk men. Officials are working on a policy proposal, which is expected by the end of the year. There will then be a public comment period before the policy is finalized.  

"We have a significant HIV epidemic in this country, and we really need to look carefully at any potential intervention that could be another tool in the toolbox we use to address the epidemic," said Kilmarx.

The CDC's endorsement may influence availability and funding for the procedure, but no one has suggested making circumcision mandatory (contrary to recent claims by conservative talk radio host Rush Limbaugh).

The discussion is sure to be heated, as circumcision carries myriad cultural, political, and religious implications, beyond its purported medical benefits. Indeed, "no-circ" advocates, talk show pundits, and newspaper editors have already begun to weigh in on the issue pro and con.

"There is no evidence that circumcision protects against male-to-male transmission of the virus, or from men to women," stated a recent Boston Globe editorial. "Still, a technique that reduces the prevalence of the disease will ultimately benefit all groups...No one should be forced to circumcise a son. But where the health benefits are clear, the CDC should be equally clear in its recommendations."

"This shouldn't even be controversial. Nearly 80 percent of adult American men are already circumcised, and they seem to be getting through life just fine," quipped the San Francisco Chronicle. "Studies have shown that circumcision can reduce HIV infection rates for heterosexual men by half. Observational studies have also shown that circumcised men have lower rates of other sexually transmitted diseases (like herpes and syphilis), cancer of the penis and urinary tract infections. What's the problem, again?"

Opponents, however, argue that it's wrong to non-consensually remove a perfectly healthy and functional body part from an infant for the sake of a small future reduction in risk that could easily be achieved by using condoms.

9/04/09

Reference

T Lane, HF Raymond, S Dladla, and others. Lower risk of HIV infection among circumcised MSM: results from the Soweto Men's Study. 5th International AIDS Society Conference on HIV Pathogenesis, Treatment and Prevention (IAS 2009). July 19-22, 2009. Cape Town, South Africa. Abstract MOPDC105.

Other sources

M Stobbe. Circumcision doesn't protect gays from AIDS virus. Associated Press. August 25, 2009.

Circumcision: A cut against HIV (Editorial). Boston Globe. August 26, 2009.

CDC should recommend routine circumcision (Editorial). San Francisco Chronicle. August 31, 2009.