Effectiveness of HIV Risk Reduction Interventions among Men who have Sex with Men in China: A Systematic Review and Meta-Analysis

Objective
To evaluate the effect of risk reduction interventions on HIV knowledge, attitudes and behaviors among men who have sex with men (MSM) in China.
Methods
We performed a systematic review and meta-analysis of HIV risk reduction intervention studies among Chinese MSM. The summary difference of standardized mean differences (SMD) between both study arms or between pre- and post-intervention assessments were defined as the effect size (ES); ES was calculated using standard meta-analysis in random effects models.
Results
Thirty-four eligible studies were included in the analysis, including two randomized clinical trials (RCT), six quasi-experimental studies, six pre-and-post intervention studies, and twenty serial cross-sectional intervention studies. These studies showed an increase in consistent condom use with any male sexual partners (mean ES, 0.46; 95% confidence interval [CI], 0.35–0.56), with regular sexual partners (mean ES, 0.41; 95% CI, 0.18–0.63), and casual sexual partners (mean ES, 0.52; 95% CI, 0.24–0.79). The analysis of ten studies that measured the impact on uptake of HIV testing also showed a positive result (mean ES, 0.55; 95% CI, 0.38–0.71). The risk reduction interventions also improved HIV/AIDS-related knowledge (mean ES, 0.77; 95% CI, 0.60–0.94) and attitudes (mean ES, 1.35; 95% CI, 0.91–1.79), but did not reduce prevalence of HIV (mean ES, 0.23; 95% CI, 0.02–0.45) and syphilis infections (mean ES, −0.01; 95% CI, −0.19–0.17). There was significant heterogeneity among these studies.
Conclusions
On aggregate, HIV risk reduction interventions were effective in reducing risky behaviors and improving knowledge and attitudes among Chinese MSM, but were not associated with a change in the prevalence of HIV and syphilis. Future studies should use incidence as definitive study outcome.

研究目标
评估人类免疫缺陷病毒（Human Immunodeficiency Virus, HIV）风险降低干预措施对中国男男性行为者（men who have sex with men, MSM）相关知识、态度及行为的影响。

研究方法
本研究针对中国男男性行为者的HIV风险降低干预研究开展系统综述与元分析（meta-analysis）。以两组研究臂间或干预前与干预后评估间的标准化均差（standardized mean differences, SMD）汇总差值作为效应量（effect size, ES）；效应量通过随机效应模型（random effects models）下的标准元分析方法计算得到。

研究结果
本分析共纳入34项符合纳入标准的研究，其中包括2项随机对照试验（randomized clinical trials, RCT）、6项类实验研究、6项干预前后研究以及20项系列横断面干预研究。研究结果显示，与任意男性性伴侣发生性行为时坚持使用安全套的比例均有所提升（平均效应量：0.46；95%置信区间（confidence interval, CI）：0.35~0.56），其中与固定性伴侣时的平均效应量为0.41（95% CI：0.18~0.63），与临时性伴侣时的平均效应量为0.52（95% CI：0.24~0.79）。针对10项评估HIV检测接受度影响的研究进行的分析同样呈现正向结果（平均效应量：0.55；95% CI：0.38~0.71）。风险降低干预措施还可改善受试者的HIV/艾滋病（Acquired Immune Deficiency Syndrome, AIDS）相关知识水平与认知态度（知识层面平均效应量：0.77，95% CI：0.60~0.94；态度层面平均效应量：1.35，95% CI：0.91~1.79），但未能降低HIV与梅毒（syphilis）的感染患病率（HIV感染平均效应量：0.23，95% CI：0.02~0.45；梅毒感染平均效应量：-0.01，95% CI：-0.19~0.17）。此外，纳入的各项研究间存在显著异质性。

研究结论
总体而言，针对中国男男性行为者的HIV风险降低干预措施可有效减少危险性行为，并提升其相关知识水平与认知态度，但未对HIV与梅毒的感染患病率产生显著影响。未来研究应将感染发病率作为研究的明确结局指标。