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

OBJECTIVE: 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.
METHODS: 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'.
RESULTS: 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.
CONCLUSION: 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.