Changing patterns of sexual risk behavior among London gay men: 1998-2008

To examine changes in the sexual behavior of London gay men between 1998 and 2008.

Gay men using London gyms were surveyed annually between 1998 and 2005, and again in 2008 (n=6064; range, 482-834 per year). Information was collected on human immunodeficiency virus (HIV) status of the respondent, unprotected anal intercourse (UAI) in the previous 3 months, type (main or casual) and HIV status of partner for UAI. Nonconcordant UAI (ncUAI) was defined as UAI with a partner of unknown or discordant HIV status. Concordant UAI (cUAI) was defined as UAI with a partner of the same HIV status ("serosorting").

Between 1998 and 2008, the percentage of men reporting UAI increased from 24.3% to 36.6% (P=0.07). This overall increase concealed important differences between nonconcordant and concordant UAI. While the percentage of men engaging in cUAI increased steadily between 1998 and 2008 (9.8%, 20.8%; P=0.01), the percentage reporting ncUAI increased between 1998 and 2001 (14.5%, 23.7%; P<0.001), decreased between 2001 and 2005 (23.7%, 15.6%; P<0.001), and then leveled off between 2005 and 2008 (15.6%, 15.7%; P=0.2). However, the percentage of men reporting ncUAI with a main partner increased between 2005 and 2008 for HIV-positive men (2.5%, 8.1%; P<0.05) and HIV negative men (2.1%, 5.5%; P=0.06). While the percentage of HIV negative men who reported cUAI with a main partner (i.e., serosorting) increased between 1998 and 2008 (12.4%, 21.1%; P<0.05), less than half established seroconcordance by testing together.

The patterns of sexual behavior among London's gay men between 1998 and 2008 were dynamic and complex. Our data suggest that HIV risk with a main partner and HIV testing among couples should be given greater priority by health promotion programmes.