Safer sex intervention for male clients of female sex workers in Tijuana, Mexico

描述(由申请人提供)：旨在降低性传播感染/艾滋病毒风险的干预措施大多未能考虑FSWs的客户，他们可能是通向普通人群的“桥梁”。我们最近对在提华纳寻找暗娼的美国和墨西哥客户进行的调查显示，艾滋病毒感染率高达4.1%，令人震惊。根据对提华纳、墨西哥和美国客户的定性和定量采访，我们开发了一种基于理论的干预(Hombre Seguro)，它使用激励性访谈、积极参与和解决问题来增加客户对性工作者避孕套的使用。我们现在提出一项随机对照试验，以测试蒂华纳这一一小时干预措施的有效性，该干预措施将招募400名艾滋病毒阴性男性(圣地亚哥县200名居民；200名蒂华纳居民)，他们报告在过去4个月内与暗娼发生了无保护措施的性行为。我们基于理论的参与式干预将与时间和信息等值的教学控制条件相比较进行评估。参与者将被招募到提华纳，在那里他们将接受由CAPI管理的基线访谈、性传播感染测试(艾滋病毒、梅毒、淋病、衣原体)和干预咨询，并在基线后4、8和12个月在提华纳或圣地亚哥进行后续访谈。我们的研究目的是：1)评估Hombre Seguro在增加FSWs患者避孕套使用率方面的有效性；2)确定干预措施在美国和墨西哥客户中是否同样有效；3)确定干预措施中基于理论的组成部分(例如，自我效能)在多大程度上代表了主要结果变化的潜在机制(例如，较低的HIV/STI发病率)；以及4)根据背景特征(例如，年龄)、背景因素(例如，性行为前/性行为中的物质使用)、性心理因素(例如，社会-性效能)和心理社会因素(例如，社会网络影响)，探讨干预效果的亚组差异。我们的主要分析方法将利用广义线性混合模型(GLMM)方法来分析重复测量。这项两国研究将通过解决男性服务对象在提华纳和圣地亚哥不断升级的艾滋病毒流行中的作用，对艾滋病毒预防研究做出重大贡献，并可能适用于在性服务工作者及其服务对象中艾滋病毒流行率较高的其他环境。 公共卫生相关性：旨在降低艾滋病毒和性传播感染(STI)风险的行为干预措施大多没有考虑女性性工作者(FSWs)的客户，因为她们可能是连接普通人群的“桥梁”。这项研究建议对墨西哥提华纳的男性客户进行一次简短的、一小时的咨询干预，以降低他们与FSWs发生无保护措施的性行为(即没有避孕套的性行为)的比率以及他们感染艾滋病毒和性传播疾病的比率。考虑到提华纳艾滋病毒感染率不断上升(如早先的研究所述)，以及大量双向越境的人，其中许多人专门从提华纳的暗娼那里购买性行为，因此为这一人群找到有效的干预措施非常重要。

DESCRIPTION (provided by applicant): Interventions designed to reduce STI/HIV risk have mostly failed to consider clients of FSWs, who may act as a 'bridge' to the general population. Our recent survey of U.S and Mexican clients seeking FSWs in Tijuana revealed a startling HIV prevalence rate of 4.1%. Based on qualitative and quantitative interviews with clients from Tijuana Mexico and the U.S. we developed a theory-based intervention (Hombre Seguro) that uses Motivational Interviewing, active participation, and problem solving to increase clients' use of condoms with FSWs. We now propose an RCT to test the efficacy of this one- hour intervention in Tijuana which will enroll 400 HIV-negative men (200 residents of San Diego County; 200 Tijuana residents) who report having unprotected sex with FSWs in the past 4 months. Our theory-based participatory intervention will be evaluated in comparison with a time and information equivalent didactic control condition. Participants will be recruited in Tijuana where they will undergo a baseline CAPI-administered interview, STI testing (HIV, syphilis, gonorrhea, Chlamydia), and intervention counseling with follow-up interviews at 4, 8, and 12 months post-baseline conducted in either Tijuana or San Diego. Our study aims are to: 1) evaluate the efficacy of Hombre Seguro to increase condom use of clients with FSWs; 2) determine if the intervention is as efficacious among U.S. versus Mexican clients; 3) determine the extent to which theoretically-based components of our intervention (e.g., self-efficacy) represent underlying mechanisms of change in primary outcomes (e.g., lower HIV/STI incidence); and 4) explore subgroup differences in efficacy of the intervention based on background characteristics (e.g., age), contextual factors (e.g., substance use before/during sex), psychosexual factors (e.g., social-sexual effectiveness), and psychosocial factors (e.g., social network influence). Our primary analytic approach will utilize a generalized linear mixed models (GLMM) approach to repeated measures analysis. This bi-national study will contribute significantly to HIV prevention research by addressing the role of male clients in the escalating HIV epidemics in Tijuana and San Diego, and could have application to other settings where HIV prevalence is high among FSWs and their clients. PUBLIC HEALTH RELEVANCE: Behavioral interventions designed to reduce risk of HIV and sexually transmitted infections (STIs) have mostly failed to consider clients of female sex workers (FSWs), who may act as a "bridge" to the general population. This study proposes to test a brief, one-hour counseling intervention with male clients in Tijuana, Mexico, to reduce their rates of unprotected sex (i.e., sex without a condom) with FSWs as well as their rates of infection with HIV and STIs. Finding an effective intervention for this population is important given the rising rates of HIV infection in Tijuana (as documented in earlier studies) and the large numbers of people crossing the border in both directions, many of them specifically to purchase sex from FSWs in Tijuana.