Explaining Differences in HIV Prevalence and Incidence in Black and White MSM

描述（由申请人提供）：黑人和白人男同性恋者在艾滋病流行率和发病率方面的明显差异是有案可据的，但数十项研究表明，艾滋病流行率的差异并不是由于黑人男同性恋者中高风险的性行为水平较高、性伴侣数量较多或吸毒较多。因此，迫切需要开展研究，探讨个人层面风险行为以外的因素（如并发性等二元和网络因素，以及社区层面的疾病负担和贫困指标等因素）及其与黑人男同性恋者艾滋病毒风险的关系。我们提出了一项针对340名HIV阴性的黑人男男性行为者和340名白人男男性行为者的前瞻性队列研究，通过基线确定和定期重新确定个人水平，双元水平和网络水平以及社区水平的因素，以更好地描述导致黑人和白人男男性行为者中HIV患病率和发病率差异的可能复杂因素。男男性接触者将采用一种描述良好的场所-时间-空间抽样方法进行招募；我们将在基线时进行访谈和艾滋病毒、性传播感染和药物检测，然后在3、6、12、18和24个月时重复访谈和检测。主要结果将是艾滋病毒、性传播感染和未确诊的艾滋病毒感染的流行率，以及艾滋病毒、艾滋病毒/性传播感染合并结果和无保护肛交的发生率。将在基线和后续访问时收集有关网络和近期合作伙伴特征的信息。分析将检查与流行或事件结果相关的个体、二元和网络以及社区水平的因素。我们的调查问卷将包括基于生态系统模型的理论驱动措施，这将使我们能够将我们的研究结果转化为未来针对黑人和白人男同性恋者的艾滋病毒预防干预措施的发展。

DESCRIPTION (provided by applicant): Stark differences in HIV prevalence and incidence between black and white MSM are well documented, but dozens of studies have shown that the differences in HIV prevalence are not attributable to higher levels of high risk sex, to higher numbers of sexual partners, or to more drug use among black MSM. Therefore, there is an urgent need to conduct studies to examine factors beyond individual-level risk behaviors (e.g., dyadic and network factors such as concurrency, and community-level factors such as neighborhood-level indicators of disease burden and poverty) and their relationship to HIV risk for black MSM. We propose a prospective cohort study of 340 HIV-negative black MSM and 340 white MSM, with baseline ascertainment and periodic re-ascertainment of individual-level, dyadic and network-level, and community-level factors to better describe the likely complex array of factors that give rise to disparities in HIV prevalence and incidence in black and white MSM. MSM will be recruited using a well- described method of venue-time-space sampling; we will administer an interview and HIV, STI, and drug testing at baseline, and then repeat both interview and testing at 3, 6, 12, 18, and 24 months. Primary outcomes will be prevalence of HIV, STI and undiagnosed HIV infection, and incidence of HIV, a combined HIV/STI outcome, and unprotected anal intercourse. Information on network and recent partner characteristics will be collected at baseline and follow-up visits. Analyses will examine individual, dyadic and network, and community level factors associated with prevalent or incident outcomes. Our questionnaire will include theoretically-driven measures based on an ecological systems model, which will allow us to translate findings from our study into the development of future HIV prevention interventions for black and white MSM. PUBLIC HEALTH RELEVANCE: MSM continue to be the most heavily impacted group in the US HIV epidemic, and black MSM are disproportinately impacted by HIV as measured by HIV prevalence and incidence. Although MSM comprise nearly half of new annual HIV case reports in the US, only 10% of currently- available best-evidence HIV prevention interventions have been tested with MSM, and none has been tested with black MSM.