TUESDAY, Oct. 7, 2008 (HealthDay News) -- A new analysis of existing research finds little evidence that circumcision protects gay men from infection with the AIDS virus, but the issue is still far from settled.
For one thing, studies conducted prior to the age of powerful AIDS drugs showed that circumcision did have a preventive effect. For another, no one has launched the most definitive type of research into the effects of circumcision on AIDS rates among gay men.
"There remains an open question as to whether circumcision will actually be a public health tool in the fight against AIDS for men who have sex with men," said Dr. Sten Vermund, director of the Vanderbilt Institute for Global Health.
It's already clear that circumcision lowers rates of AIDS infection by 50 percent to 60 percent among heterosexual men. Circumcision appears to provide protection, because it rids a man of cells inside the foreskin that seem to be especially susceptible to AIDS infection, explained study author Gregorio A. Millett, a senior behavioral scientist with the Centers for Disease Control and Prevention.
But the effects of circumcision on gay men have remained a topic of intense debate. "People are interested in finding out what other things can we add to the HIV arsenal," Millett said. "As for now, we're not sure [circumcision] is something we can add to the arsenal."
In the new study, Millett and colleagues conducted a meta-analysis of 15 studies that looked at a total of more 53,000 men, 52 percent of whom were circumcised. The findings are in the Oct. 8 issue of the Journal of the American Medical Association.
The more recent studies that the researchers analyzed failed to find a statistically significant protective effect from circumcision.
However, circumcised men had a 53 percent lower risk of becoming infected with HIV prior to 1996, the era that preceded the use of powerful AIDS drugs, Millett said. The meaning of that number isn't clear; it's possible that many of the men who avoided HIV infection in the older studies engaged in less risky sex, he added.
Vermund said the question of whether circumcision protects gay men from HIV won't be answered until a clinical trial is conducted. Such a study may require some participants to undergo circumcision to understand how it affects their risk of HIV.
Vermund, co-author of a commentary accompanying the new study, added: "It would be nice if the global community would say, 'Look, we continue to have a horrific problem in men who have sex with men around the world. We need to know whether circumcision is a tool that could reduce the incidents, and we're not going to know that unless we do the clinical trials.'"
Such a study would be difficult to launch in the United States, he said, but it might be possible in South America, where gay men are less likely to be circumcised.
Learn more about HIV and circumcision from the Centers for Disease Control and Prevention.