[Analysis on the relationship between condom social norms and unprotected anal intercourse among men who have sex with men in Beijing].

ABSTRACT

OBJECTIVE: To understand the prevalence of and factors associated with unprotected anal intercourse (UAI) among men who have sex with men (MSM) in Beijing. METHODS: Five hundred MSM were recruited for a survey using Respondent Driven Sampling (RDS) method, from September to October in 2009. A computer-assisted, interviewer-administered questionnaire was used to gather information including demographics, sexual behaviors and condom use social norms (a scaled number). Variables were evaluated by using RDSAT and SAS software. RESULTS: Mean age of the participants was 30.6 years, with 96.0% of them as Han ethnicity and 68.5% having had at least high school or higher education level. 72.8% of them were unmarried, with 61.7% of them identified themselves as homosexual, 61.2% had > 1 male partners in the past six months, and the prevalence of UAI was 42.0%. Significant bivariate predictors of UAI would include condom use social norms score, role for anal sex with male sex partner, number of male sexual partners in the past 6 months and amount of alcohol consumed. In multivariable analysis, UAI was associated with a higher condom use social norms score (AOR = 1.2, 95%CI 1.1 - 1.3), receptive anal intercourse (AOR = 2.0, 95%CI 1.3 - 3.2) and drinking alcohol more than 3 times per month in the past 12 months (AOR = 1.6, 95%CI 1.1 - 2.5). CONCLUSION: The prevalence of UAI was high in the MSM community in Beijing, suggesting that efforts should be targeting on how to make the condom use a social norm and being promoted.