High-risk sexual behaviour increases among London gay men between 1998 and 2001: what is the role of HIV optimism?

Abstract
To examine whether HIV optimism (i.e. optimism in the light of new HIV drug therapies) can account for the recent increase in high-risk sexual behaviour among London gay men. Gay men (n = 2938) using London gyms were surveyed annually between 1998 and 2001. Information was collected on HIV status, unprotected anal intercourse (UAI) in the previous 3 months, and agreement with two statements concerning the severity of and susceptibility to HIV infection. Those who agreed were classified as 'optimistic'. Between 1998 and 2001, the percentage of men reporting high-risk UAI (i.e. UAI with a casual partner of unknown or discordant HIV status) increased: HIV-positive men 15.3-38.8%; HIV-negative men 6.8-12.1%; never-tested men 2.1-7.7%; (P < 0.01). Overall, less than a third were optimistic. In cross-sectional analysis, optimistic HIV-positive and -negative men were more likely to report high-risk UAI than other men (P < 0.05). However, the increase in high-risk UAI between 1998 and 2001 was seen in those who were optimistic and those who were not (P < 0.05). In multivariate analysis, the modelled increase in high-risk UAI over time remained significant after controlling for HIV optimism (P < 0.01), with no significant interaction between optimism and time. Among London gay men, no difference was detected between those who were optimistic and those who were not in the rate of increase in high-risk sexual behaviour between 1998 and 2001. Our findings suggest that HIV optimism is unlikely to explain the recent increase in high-risk sexual behaviour in these men.