Risk factors for HIV infection among men who have sex with men.

OBJECTIVES Risk factors for HIV acquisition were examined in a recent cohort of men who have sex with men (MSM). DESIGN A longitudinal analysis of 4295 HIV-negative MSM enrolled in a randomized behavioral intervention trial conducted in six US cities. METHODS MSM were enrolled and assessed for HIV infection and risk behaviors semi-annually, up to 48 months. RESULTS In multivariate analysis, men reporting four or more male sex partners, unprotected receptive anal intercourse with any HIV serostatus partners and unprotected insertive anal intercourse with HIV-positive partners were at increased risk of HIV infection, as were those reporting amphetamine or heavy alcohol use and alcohol or drug use before sex. Some depression symptoms and occurrence of gonorrhea also were independently associated with HIV infection. The attributable fractions of high number of male partners, use of alcohol or drugs before sex, and unprotected receptive anal intercourse with unknown status partners and the same with presumed negative partners accounted for 32.3, 29.0, 28.4 and 21.6% of infections, respectively. CONCLUSIONS The challenge is to develop strategies to identify men in need. Interventions are needed to help men reduce their number of sexual partners, occurrences of unprotected anal intercourse, alcohol or drug use before sex and address other mental health issues.