Risky Sex Practices That May Increase Risk for Getting HCV Among Men Who Have Sex With Men

Craib and colleagues reported a follow-up to their poster at last year's Retrovirus Conference, on evidence supporting sexual transmission & modes of transmission among men who have sex with men. This study aimed to determine HCV prevalence & identify risk factors for HCV in a group of sexually active MSM in Bristish Vancouver, Canada. Stored blood samples (obtained during '82-'98) from 662 individuals were tested for HCV antibody and demographics, sexual practices, substance abuse, etc were obtained by self-administered questionnaires completed during '82-'98. Case-control comparisons were made and multivariate regression analysis was used to identify risk factors for being HCV+.

5.9% (39/662) were HCV+. HCV positivity was significantly higher among HIV+ men than HIV- men (8.8% 31/352 vs 2.6% 8/310).

HCV+ men were more likely to:

• Have more sexual partners in previous year (>20 partners: 74% vs 48%, p=0.002) & in their lifetime (>100 partners: 82% vs 64%, p=0.024)
• HCV+ men were more likely to report insertive fisting (49% vs 27%, p=0.003)
• HCV+ men were more likely to report receptive anal intercourse (62% vs 45%, p=0.043), and oral-anal contact (90% vs 73%, p=0.019)
• HCV+ men were more likely to report using injection drugs during their lifetime (51% vs 3%, p<0.001), and use of the following substances during the last year: MDA (64% vs 37%, p<0.001), LSD (49% vs 26%, p=0.002), amphetamine (28% vs 14%, p=0.013), cocaine (46% vs 30%, p=0.029), and tobacco (67% vs 48%, p=0.027)

19 (49%) of the 39 HCV+ individuals reported never using IV drugs. In comparing these 19 individuals with the 589 HCV- non-IV drug users, oral-anal contact (95% vs 72%, p=0.029) and insertive fisting (51% vs 26%, p=0.012) were significant risk factors for being HCV+.

Multivariate analysis showed IVDU (P<0.001), HIV positivity (p=0.042), and number of male sex partners in the previous years to be independent risk factors for being HCV+, and these were statistically significantly.

Craib concluded IVDU was not surprisingly a significant risk factor for HCV infection. But, 49% of the HCV+ men did not report using IV drugs and among them specific sex practices (that might facilitate blood exchange) were identified as risk factors for getting HCV.