The study

While a couple of studies have reported that circumcision is protective of gay men who are exclusive tops, more studies have not. Most studies have taken place in the US, where nearly 80% of men are circumcised; in a country like the UK, where only a minority of men are circumcised, this could conceivably make it easier – or more difficult – to isolate any protective role circumcision might have in gay men.

The study is one of a series of findings drawn from the Men and Sexual Health (MESH) Project, which interviewed gay men about their personal characteristics, HIV status and sexual risk behaviour.

It also asked about ‘HIV treatment optimism’. It did this by asking whether or not respondents agreed with two statements: “I am less worried about HIV now that treatments have improved” and “I believe that drug therapies make people with HIV less infectious”.

Interestingly, in early 2008, only 22% agreed with the first statement and only 18% with the second.

Although the primary focus of the MESH Project was to find out more about black and other ethnic-minority gay men in the UK – and aidsmap.com has previously reported on its findings on African gay and bisexual men and on sexual risk behaviour in gay men from different ethnic minorities – it also gathered enough data on circumcision status to conduct the present analysis. Non-UK-born men were specifically excluded to avoid confounders between circumcision and other culturally influenced behavioural and biological factors.

MESH ran on the UK’s largest gay dating site Gaydar and was also conducted offline in STI clinics, bars and clubs in 15 UK cities between October 2007 and February 2008.

Results

Over 17,000 men responded to the survey, of whom over 13,000 reported their HIV status. Nearly 12,000 of these were white UK nationals and of them 4898 (41.5%) said they had had unprotected anal intercourse in the previous three months and indicated what sexual role they took.

Of these 4898 who had unprotected sex, 1521 (31%) reported that they mainly (960, 20%) or exclusively (561, 11%) took the insertive role, and the present paper looks exclusively at HIV prevalence among these 1521 men.

Of these men, one in six (16.7%) were circumcised. Interestingly, there were demographic differences between circumcised and uncircumcised men. The former were on average older (41 versus 36); because of this, were more likely to be retired; and were more likely to have had tertiary education. This reflects a continuing decline in circumcision in the UK over time (only 9% of UK boys are now circumcised as babies).

Of the 1521 men, 1097 had taken an HIV test (72%) and circumcised men were more likely to have done so (78%). Ninety-seven men (8.8%) reported that they had HIV and there was no difference in HIV prevalence between circumcised (8.6%) and uncircumcised (8.9%) men.

Being exclusively as opposed to mainly top was highly protective against HIV, as other studies have found: 5% of exclusively insertive men were HIV positive as opposed to 11% mainly insertive men – a 58% reduction in HIV risk. A previous study has shown that being an exclusive top confers an 89% reduced rate of HIV versus all other sex roles.

Even in exclusively insertive men, though, there was no difference in HIV status between circumcised (5.3%) and uncircumcised (4.9%) men (odds ratio 1.08). Controlling for place of residence, unprotected sex, recreational drug use and beliefs about HIV treatment and infectiousness turned an 8% greater likelihood of infection in circumcised men into a 16% reduced likelihood, but this was still nowhere near statistical significance.

In these categories, we are comparing small figures (22 uncircumcised and 6 circumcised exclusive tops with HIV) and so have a wide 95% confidence interval of 0.25 to 2.81 in the multivariate analysis, so circumcision could conceivably still offer some degree of protection that could be detected in a larger study; all we can say from this one is that there is no statistical association between circumcision and HIV infection, even in exclusive tops, and no difference between men who were mainly and men who were exclusively top. There is certainly nothing approaching the 60 to 70% reductions in HIV risk seen in randomised controlled trials of heterosexual men in Africa.

This study also looked at syphilis prevalence (1.7%) and similarly found no protective role of circumcision.

Implications

Why is circumcision not protective in gay men who are exclusively insertive? The theory that respondents might be not accurately reporting their chosen sex role because of stigma against being receptive does not appear to hold up because the reported proportion of exclusive tops in this study is almost identical to that reported from a number of other gay men’s behavioural studies.

The explanation is therefore likely to be physiological, which could have important implications for why HIV is more easily transmitted during anal than vaginal sex; reasons could include the greater likelihood of trauma, the presence of an alkaline rather than acid environment in the rectum, and that the greater likelihood of transmission into or from the fragile rectal mucosa overwhelms any protective effect of circumcision. This does not explain, however, why taking an exclusively insertive role is very protective whereas circumcision is not.

The main conclusion to be drawn is that a study with a reasonably large sample has confirmed that circumcision is unlikely to protect gay men from HIV and therefore would not be an effective HIV prevention strategy for gay men in general, regardless of their preferred sex role.

Reference

Doerner R et al. Circumcision and HIV infection among men who have sex with men in Britain: the insertive sex role. Archives of Sexual Behavior, early online edition, DOI 10.1007/s10508-012-0061-1, 2013.

This article was first published by NAM/Aidsmap.com and is republished with permission.