Nosyk Bohdan, Min Jeong E, Colley Guillaume, Lima Viviane D, Yip Benita, Milloy M-J S, Wood Evan, Montaner Julio S G
aBC Centre for Excellence in HIV/AIDS, St Paul's Hospital, Vancouver bFaculty of Health Sciences, Simon Fraser University, Burnaby cDivision of AIDS, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada.
AIDS. 2015 May 15;29(8):965-73. doi: 10.1097/QAD.0000000000000642.
People who inject drugs (PWID) account for roughly 13% of the prevalent HIV/AIDS population outside of sub-Saharan Africa, and access to opioid substitution treatment (OST) is limited in many settings globally. OST likely facilitates access to HAART, yet sparse evidence is available to support this hypothesis. Our objective was to determine the causal impact of OST exposure on HAART adherence among HIV-positive PWID in a Canadian setting.
We executed a retrospective cohort study using linked population-level data for British Columbia, Canada (January 1996-March 2010). We considered HIV-positive PWID after meeting HAART initiation criteria. A marginal structural model was estimated on a monthly timescale using inverse probability of treatment weights. The primary outcome was 95% HAART adherence, according to pharmacy refill compliance. Exposure to OST was defined as 95% of OST receipt, and we controlled for a range of fixed and time-varying covariates.
Our study included 1852 (63.3%) HIV-positive PWID with a median follow-up of 5.5 years; 34% were female and 39% had previously accessed OST. The baseline covariate-adjusted odds of HAART adherence following OST exposure was 1.96 (95% confidence interval: 1.72-2.24), although the adjusted odds estimated within the marginal structural model was 1.68 (1.48-1.92). Findings were robust to sensitivity analyses on model specification.
In a setting characterized by universal healthcare and widespread access to both office-based OST and HAART, OST substantially increased the odds of HAART adherence. This underlines the need to address barriers to OST globally to reduce the disease burden of both opioid dependence and HIV/AIDS.
在撒哈拉以南非洲以外地区，注射吸毒者（PWID）约占艾滋病病毒/艾滋病流行人群的13%，而且在全球许多地区，获得阿片类药物替代治疗（OST）的机会有限。OST可能有助于获得高效抗逆转录病毒治疗（HAART），但支持这一假设的证据很少。我们的目标是确定在加拿大环境中，接受OST对HIV阳性PWID的HAART依从性的因果影响。
我们利用加拿大不列颠哥伦比亚省（1996年1月至2010年3月）的关联人群水平数据进行了一项回顾性队列研究。我们考虑了符合HAART启动标准后的HIV阳性PWID。使用治疗权重的逆概率在每月时间尺度上估计边际结构模型。主要结局是根据药房配药依从性得出的95%的HAART依从性。OST暴露定义为95%的OST接受情况，我们控制了一系列固定和随时间变化的协变量。
我们的研究纳入了1852名（63.3%）HIV阳性PWID，中位随访时间为5.5年；34%为女性，39%曾接受过OST。接受OST暴露后，经基线协变量调整的HAART依从性优势比为1.96（95%置信区间：1.72 - 2.24），尽管在边际结构模型中估计的调整后优势比为1.68（1.48 - 1.92）。研究结果对模型规范的敏感性分析具有稳健性。
在一个具有全民医疗保健以及广泛获得基于诊所的OST和HAART机会的环境中，OST显著增加了HAART依从性的几率。这凸显了在全球范围内解决OST障碍以减轻阿片类药物依赖和艾滋病病毒/艾滋病疾病负担的必要性。
