Risk Compensation after Biomedical Interventions to Prevent HIV Among Peruvian MSM

摘要 在秘鲁，艾滋病毒对男男性行为者和变性妇女的影响尤为严重， 他们的患病率估计是普通人群的20倍以上。治疗作为预防 （TasP）是一种预防艾滋病毒的生物医学方法，使用早期开始抗逆转录病毒治疗（ART），以减少 体液中的艾滋病毒水平，从而降低艾滋病毒传播的可能性。暴露前预防 （PrEP）是一种预防方法，涉及向HIV阴性者提供抗逆转录病毒药物，以预防 艾滋病毒的获得。虽然这些方法已被证明是非常有效的预防艾滋病毒的男男性行为者 和TGW，它们不能防止其他性传播感染（STIs），人们担心， 这些艾滋病毒预防策略将导致风险补偿-由于以下因素的变化而导致的行为变化： 个人风险的认知水平。在预防艾滋病毒方面，风险补偿可采取以下形式： 减少使用避孕套或其他可能增加性传播感染风险的性行为改变。的首要目标 这项建议是为了衡量秘鲁男男性行为者和女同性恋者的性行为和性传播感染率的变化， 我们正在使用TasP和PrEP。为此，我们计划首先开发一个描述总体趋势的上下文框架 在过去两年中，秘鲁男男性行为者和女同性恋者的性传播感染率和性行为模式 在秘鲁的这一亚群中进行了一系列横断面调查， 1996年和2011年。然后，我们将测试ART的使用是否与性行为或STI的变化有关 使用线性回归和双样本z-检验， 描述性行为随时间变化的总体模式以及ART性行为差异的测试 status.最后，我们将测试PrEP的启动是否与STI发病率或性行为的变化相关。 使用PrEP的MSM和TGW队列中的行为，使用纵向数据和混合效应回归 描述性传播感染发病率和性行为随时间变化的幅度和方向的模型， 识别行为和性传播感染风险的即时和延迟变化。这项研究将提供有价值的 关于性行为是否因使用抗逆转录病毒疗法预防艾滋病毒而改变的信息，以及 当这些变化发生时。这些信息可用于制定新的战略， 与这些新的艾滋病毒预防方法相关的性传播感染风险的潜在增加，并确定这些方法何时 战略将得到最好的应用。

ABSTRACT In Peru, HIV disproportionately affects men who have sex with men (MSM) and transgender women (TGW), who have an estimated prevalence more than 20 times that of the general population. Treatment as prevention (TasP) is a biomedical method of preventing HIV using early initiation of antiretroviral therapy (ART) to reduce the level of HIV in bodily fluids, thus reducing the likelihood of HIV transmission. Pre-exposure prophylaxis (PrEP) is a prevention method that involves giving antiretroviral medication to HIV-negative people to prevent acquisition of HIV. While these methods have been shown to be highly effective in preventing HIV among MSM and TGW, they do not protect against other sexually transmitted infections (STIs), and there are concerns that these HIV prevention strategies will lead to risk compensation – changes in behavior resulting from changes in perceived level of personal risk. In the context of HIV prevention, risk compensation could take the form of decreases in condom use or other changes in sexual behavior that may increase STI risk. The primary goal of this proposal is to measure changes in sexual behavior and STI rates among Peruvian MSM and TGW who are using TasP and PrEP. To do this, we plan to first develop a contextual framework describing overall trends of STI prevalence and patterns of sexual behavior among Peruvian MSM and TGW during the past two decades, using data from a series of cross-sectional surveys conducted in this subpopulation in Peru between 1996 and 2011. Then we will test whether ART use is associated with changes in sexual behavior or STI incidence in a cohort of MSM and TGW participating in a TasP trial, using linear regression and two-sample z- tests to describe overall patterns in sexual behavior over time, and differences in sexual behavior by ART status. Finally, we will test whether initiation of PrEP is associated with changes in STI incidence or sexual behavior in a cohort of MSM and TGW utilizing PrEP, using longitudinal data and mixed effects regression models to describe changes in magnitude and direction of STI incidence and sexual behavior over time, identifying both immediate and delayed changes in behavior and STI risk. This study will provide valuable information on whether sexual behavior changes as a result of using antiretroviral therapy to prevent HIV, and when these changes are taking place. This information can be used to develop new strategies to address potential increases in STI risk associated with these new HIV prevention methods, and to identify when these strategies would be best applied.