HIV incidence among men who have sex with men in Beijing: a prospective cohort study.

OBJECTIVES: (1) To assess the HIV incidence rate among men who have sex with men (MSM) in a large cohort study in Beijing, China and (2) to identify sociodemographic and behavioural risk factors of HIV seroconversion among MSM in Beijing, China. DESIGN: A prospective cohort study. SETTING: Baseline and follow-up visits were conducted among MSM in Beijing, China. PARTICIPANTS: A cohort of 797 HIV-seronegative MSM was recruited from August to December 2009, with follow-up occurring after 6 and 12 months. PRIMARY AND SECONDARY OUTCOME MEASURES: At baseline and follow-up visits, participants reported sociodemographic and sexual behaviour information, and were tested for HIV, herpes simplex virus-2 (HSV-2) and syphilis with whole blood specimens. Cox regression analysis was used to identify factors associated with HIV seroconversion. RESULTS: Most study participants (86.8%) were retained by the 12-month follow-up. The HIV, HSV-2 and syphilis incidence rates were 8.09 (95% CI 6.92 to 9.26), 5.92 (95% CI 5.44 to 6.40) and 8.06 (95% CI 7.56 to 8.56) cases per 100 person-years, respectively. HIV seroconversion was significantly associated with being <25 years old, having <12 years of education, having >1 male sex partner in the past 6 months, and being syphilis positive or HSV-2 positive. CONCLUSIONS: The HIV incidence among MSM in Beijing is serious. Interventions and treatment of sexually transmitted diseases (STD) should be combined with HIV control and prevention measures among MSM.

[Study on the incidence of HIV and associated risk factors through a prospective cohort among men who have sex with men in Beijing, China].

OBJECTIVE: To investigate the dynamic change and associated risk factors of HIV sero-conversion rate in Beijing. METHODS: 809 sero-negative men who have sex with men (MSM) were recruited in the cohort from August to December in 2009. HIV sero-antibody, medicinal examination and behavior questionnaire interview were carried out every six months. RESULTS: 962 MSM with overall baseline prevalence of HIV infection as 6.34% (61/962) together with 809 sero-negative MSM, were enrolled in the cohort. Of the 809 sero-negative participants, 95.1% (769/ 809), 85.5% (692/809) and 71.0% (574/809) of them were retained in the 6-month, 12-month and 18-month follow-up visits, with 19, 29 and 17 of them became HIV sero-conversion at 6-month, 12-month, and 18-month follow-up visits and the HIV incidence rates appeared to be 5.47, 12.37 and 6.86 per 100 person-years respectively. The HIV incidence was 7.59 per 100 person-years in the 18 months follow-up visit. Factors including: younger than 25-years old (HR = 2.32, 95%CI: 1.39 - 3.87), having more than 8 MSM partners (HR = 2.50, 95%CI: 1.49 - 4.20), less than 2000¥ every month income (HR = 1.76, 95%CI: 1.05 - 2.95), having more than 4 homosexual partners in the last six months (HR = 3.50, 95%CI: 2.11 - 5.81), showing phimosis and redundant prepuce (HR = 2.47, 95%CI: 1.50 - 4.07) as well as positive syphilis test (HR = 2.62, 95%CI: 1.53 - 4.49) etc., were significantly associated with HIV incidence. CONCLUSION: High HIV incidence was shown among MSM in Beijing and had spread fast in this population, calling for more favorable prevention measures to be taken.