[HIV infection rate, high-risk behavior and pre-exposure prophylaxis/post-exposure prophylaxis in men who have sex with men in Beijing].

Objective: To understand the incidence of HIV infection, high risk behaviors and pre-exposure prophylaxis/post-exposure prophylaxis (PrEP/PEP) utilization in men who have sex with men (MSM) in Beijing. Methods: Sample size was estimated to be 1 227 persons and 207 person year respectively in the survey and the cohort by using Epi Info 7.0 software. Using convenient sampling method, MSM were recruited by using Wechat app. Questionnaire was completed online to collect the information about demographic characteristics, high risk behavior, and utilization of PrEP/PEP of the MSM. MSM collected dry blood spot (DBS) samples by themselves, and mailed the DBS samples to laboratory for HIV nucleic acid testing. Open cohort was established and those with HIV negative nucleic acid testing results were followed up. Non-conditional binary logistic regression method was used to identify the associated factors for high risk anal sex in the last month and having multiple homosexual partners in the last month. Results: A total of 1 147 MSM were recruited, and follow up for 236 person years was conducted in 956 MSM with negative HIV nucleic acid testing results. The detection rate of new HIV infection was 1.3 per 100 person-years (3/236). During the last month, the proportions of consistent condom use in anal sex and oral sex were 50.7% (238/469) and 4.9% (23/469). In the MSM, 5.9% (43/723) had sex with HIV positive partners in the last month. 9.8% (103/1 049) used PrEP, and 8.7% (91/1 049) used PEP. The proportion of consistent condom use in PrEP and PEP were 34.3% (24/70) and 72.2% (39/54) respectively. Logistic regression analysis revealed that compared with those who used no PrEP/PEP, those who used PrEP/PEP were more likely to have unprotected anal sex in the last month (aOR=3.16, 95%CI:1.45-7.18), and more likely to have multiple homosexual partners in the last month (aOR=2.64, 95%CI:1.19-6.30), and compared with those who used no Rush Popper or drugs in the last month, those who used Rush Popper or drugs in the last month were more likely to have unprotected anal sex in the last month (aOR=2.34, 95%CI:1.67-3.30), and more likely to have multiple homosexual partners (aOR=2.42,95%CI:1.76-3.33). Conclusions: It is necessary to strengthen the health education to promote condom use and introduce the harm of drug use in MSM. In PrEP and PEP services, it is still necessary to suggest consistent condom use for MSM.目的： 了解北京市MSM的HIV新发感染率与高危行为及接受暴露前后预防（PrEP/PEP）用药服务情况。 方法： 采用Epi Info7.0软件计算参加横断面调查和队列调查样本量分别为1 227人和207人年。采用方便抽样法通过手机微信公众号招募MSM参加自填式网络问卷调查，收集其社会人口学、高危行为及接受PrEP/PEP用药服务利用情况，MSM自行采集干血斑样本邮寄到指定实验室进行HIV核酸检测。建立HIV核酸阴性受检者开放式队列，随访观察至研究终点。采用非条件logistic回归分析MSM最近1个月无保护肛交行为、最近1个月同性多性伴的影响因素。 结果： 共招募MSM 1 147人，其中HIV核酸阴性者956人观察236人年。HIV新发感染率为1.3/100人年（3/236）。最近1个月肛交和口交每次都使用安全套者分别占50.7%（238/469）和4.9%（23/469）。最近1个月与HIV感染者发生性行为的比例为5.9%（43/723）。分别有9.8%（103/1 049）和8.7%（91/1 049）的研究对象曾接受PrEP/PEP用药服务。PrEP/PEP用药期间发生性行为每次使用安全套的比例分别为34.3%（24/70）和72.2%（39/54）。多因素logistic回归分析结果显示，接受PrEP/PEP用药服务者的最近1个月发生无保护肛交行为和有同性多性伴的可能性均较高（aOR=3.16，95%CI：1.45~7.18；aOR=2.64，95%CI：1.19~6.30）；最近1个月使用毒品或Rush Popper者的最近1个月发生无保护肛交行为和有同性多性伴的可能性均较高（aOR=2.34，95%CI：1.67~3.30；aOR=2.42，95%CI：1.76~3.33）。 结论： 应在MSM中倡导坚持使用安全套及开展常见滥用药物危害的健康教育。在PrEP/PEP用药服务咨询中，需提示MSM坚持使用安全套的重要性。.