Lower HIV Risk Among Circumcised Men Who Have Sex With Men in China: Interaction With Anal Sex Role in a Cross-Sectional Study.

BACKGROUND

Voluntary medical male circumcision reduces the risk of HIV heterosexual transmission in men, but its effect on male-to-male sexual transmission is uncertain.

METHODS

Circumcision status of men who have sex with men (MSM) in China was evaluated by genital examination and self-report; anal sexual role was assessed by questionnaire interview. Serostatus for HIV and syphilis was confirmed.

RESULTS

Among 1155 participants (242 were seropositive and 913 with unknown HIV status at enrollment), the circumcision rate by self-report (10.4%) was higher than confirmed by genital examination (8.2%). Male circumcision (by examination) was associated with 47% lower odds of being HIV seropositive [adjusted odds ratio (aOR): 0.53; 95% confidence interval (CI): 0.27 to 1.02] after adjusting for demographic covariates, number of lifetime male sexual partners, and anal sex role. Among MSM who predominantly practiced insertive anal sex, circumcised men had 62% lower odds of HIV infection than those who were uncircumcised (aOR: 0.38; 95% CI: 0.09 to 1.64). Among those whose anal sex position was predominantly receptive or versatile, circumcised men have 46% lower odds of HIV infection than did men who were not circumcised (aOR: 0.54; 95% CI: 0.25 to 1.14). Compared to uncircumcised men reporting versatile or predominantly receptive anal sex positioning, those who were circumcised and reported practicing insertive sex had an 85% lower risk (aOR: 0.15; 95% CI: 0.04 to 0.65). Circumcision was not associated clearly with lower syphilis risk (aOR: 0.91; 95% CI: 0.51 to 1.61).

CONCLUSIONS

Circumcised MSM were less likely to have acquired HIV, most pronounced among men predominantly practicing insertive anal intercourse. A clinical trial is needed.