Percentage of gay men in London reporting high risk sex increased significantly between 1998 and 2003

This article is more than 19 years old. Click here for more recent articles on this topic

The percentage of gay and bisexual men in London reporting unprotected anal sex with a casual partner increased significantly between 1998 and 2003, according to a study published in the December 2004 edition of Sexually Transmitted Infections. Although the investigators note that this increase in high risk sexual behaviour has coincided with the introduction of HAART, they do not believe that the availability of effective anti-HIV treatment can explain changes in behaviour at a population level and call, as a priority, for further research to understand the sexual behaviour of gay and bisexual men in the UK’s capital.

Since 1998 gay and bisexual men attending gyms in central London have been asked to complete a questionnaire enquiring about their HIV status, their sexual risk behaviour, and the HIV status of their partners. The confidential questionnaire also included items on demographics, steroid use, and use of the internet to seek sex.

Men completing the questionnaire were asked to say if they had had unprotected anal sex in the previous three months, and if so, if it was with a main or casual partner, and what their partner’s HIV status was. Unprotected anal sex was then classified by the investigators as being concordant (between men of the same HIV status), or non-concordant (with a man of a different or unknown status).


statistical significance

Statistical tests are used to judge whether the results of a study could be due to chance and would not be confirmed if the study was repeated. If result is probably not due to chance, the results are ‘statistically significant’. 

risky behaviour

In HIV, refers to any behaviour or action that increases an individual’s probability of acquiring or transmitting HIV, such as having unprotected sex, having multiple partners or sharing drug injection equipment.

A total of 4264 men were included in the investigator analysis. A total of 654 men (15%) said they were HIV-positive, 2652 (62%) said they were HIV-negative and 958 men (23%) reported never having had an HIV test.

Between 1998 and 2003, there was a significant increase in the percentage of men reporting both non-concordant unprotected anal sex (15% to 22%, p

Only a very small minority of men reported having unprotected anal sex with a man whose HIV status they knew to be different from their own. The investigators highlight 2002 as an example. Of the 181 men who reported non-concordant unprotected sex, 167 said that it was with men whose HIV status they did not know, and only 14 men (1.7%) said it was with a man whose HIV status was known to be different from their own.

The increase of non-concordant anal sex was only seen with casual partners (7% to 16%, p

After controlling for HIV optimism, steroid use and relationship status, the increase in non-concordant unprotected sex with a casual partner between 1998 and 2003 remained statistically significant for HIV-positive, HIV-negative and untested men (p

HIV-positive men were more likely in all years to report non-concordant unprotected anal sex with a casual partner than with a primary partner (p

Investigators also looked at data concerning unprotected anal sex between casual partners of the same HIV status. The percentage of HIV-positive men reporting unprotected anal sex with other HIV-positive men during casual encounters increased significantly between 1998 (7%) and 2003 (10%, p

The percentage of HIV-negative men reporting concordant unprotected sex with a main partner alone increased significantly between 1998 and 2003 (12% to 16%, p

“The increase in high risk sexual behaviour among London homosexual men between 1998 and 2003 was seen only with casual partners and not with main partners”, write the investigators, “STI/HIV prevention interventions among these men should therefore target high risk practices with casual partners since these appear to account entirely for the recent increase in high risk sexual behaviour”, they add.

Similar increases in non-concordant unprotected anal sex have also been noted, the investigators comment, amongst London gay men surveyed in bars and clubs, and amongst gay men attending sexual health services.

The investigators offer various explanations for the increase in high-risk sexual activity amongst London’s gay men since 1998. They note that although the increase in unprotected anal sex with casual partners of unknown or different HIV status coincided with the introduction and widespread use of HAART “it is unlikely that optimism in the light of new treatments can explain the increase at a population level.”

Other factors could be the increased opportunities for sex afforded by bars offering backrooms, saunas and the internet. In addition, it is possible that gay men have become “habituated to the risk of HIV now that more than two decades have passed since the AIDS was first reported.” Another possibility offered by the investigators is the increased pressure placed on HIV prevention services by the shift of emphasis onto providing treatment. The investigators conclude that “priority should be given to research which helps us to better understand the factors that underlie high risk sexual behaviour among homosexual and bisexual men living in London.”


Elford J et al. Trends in sexual behaviour among London homosexual men 1998 – 2003: implications for HIV prevention and sexual health promotion. Sex Transm Infect 80: 451 - 454, 2004.