University of California, Los Angeles, Los Angeles, USA.
BMC Infect Dis. 2014 Jun 11;14:322. doi: 10.1186/1471-2334-14-322.
Previous cohort studies have demonstrated the beneficial effects of antiretroviral therapy (ART) on viral load suppression. We aimed to examine the factors associated with virologic suppression for HIV-infected patients on ART receiving care at the Evandro Chagas Clinical Research Institute, Oswaldo Cruz Foundation in Rio de Janeiro, Brazil.
HIV-1 RNA levels and CD4+ T-cell counts at the date closest to midyear (1 July) were evaluated for 1,678 ART-naïve patients ≥ 18 years of age initiating ART between 1997 and 2010. The odds ratios (OR) and 95% confidence intervals (CI) for having an undetectable viral load (≤ 400 copies/mL) were estimated using generalized estimating equations regression models adjusted for clinical and demographic factors. Time-updated covariates included age, years since HIV diagnosis, hepatitis C diagnosis and ART interruptions.
Between 1997 and 2011, the proportion of patients with an undetectable viral load increased from 6% to 78% and the median [interquartile range] CD4+ T-cell count increased from 207 [162, 343] to 554 [382, 743] cells/μL. Pre-treatment median CD4+ T-cell count significantly increased over the observation period from 114 [37, 161] to 237 [76, 333] cells/μL (p < .001). The per-year adjusted OR (aOR) for having undetectable viral load was 1.18 (95% CI = 1.16-1.21). ART interruptions >1 month per calendar significantly decreased the odds [aOR = 0.32 (95% CI = 0.27-0.38)] of having an undetectable viral load. Patients initiating on a protease inhibitor (PI)-based first-line regimen were less likely to have undetectable viral load [aOR = 0.72 (95% CI = 0.63-0.83)] compared to those initiating on a non-nucleoside reverse transcriptase inhibitor (NNRTI)-based regimen.
Our results demonstrate significant improvements in virologic outcomes from 1997 to 2011, which persisted after adjusting for other factors. This may in part be due to improvements in care and new treatment options. NNRTI- versus PI-based first-line regimens were found to be associated with increased odds of having an undetectable viral load, consistent with previous studies. Treatment interruptions were found to be the most important determinant of not having an undetectable viral load. Studies are needed to characterize the reasons for treatment interruptions and to develop subsequent strategies for improving adherence to ART.
先前的队列研究表明，抗逆转录病毒疗法（ART）可有效抑制病毒载量。本研究旨在探讨在巴西里约热内卢 Oswaldo Cruz 基金会 Evandro Chagas 临床研究所接受治疗的接受 ART 的 HIV 感染者病毒学抑制相关因素。
对 1997 年至 2010 年间首次接受 ART 的 18 岁及以上的 1678 名 ART 初治患者，评估其在接近年中（7 月 1 日）时的 HIV-1 RNA 水平和 CD4+T 细胞计数。使用广义估计方程回归模型，根据临床和人口统计学因素调整，估计具有不可检测病毒载量（≤400 拷贝/ml）的比值比（OR）和 95%置信区间（CI）。时间更新的协变量包括年龄、HIV 诊断后时间、丙型肝炎诊断和 ART 中断。
1997 年至 2011 年间，不可检测病毒载量的患者比例从 6%增加到 78%，中位[四分位间距]CD4+T 细胞计数从 207[162,343]增加到 554[382,743]个/μL。治疗前中位 CD4+T 细胞计数在观察期间显著增加，从 114[37,161]增加到 237[76,333]个/μL（p<0.001）。每年调整后的 OR（aOR）为 1.18（95%CI=1.16-1.21）。每日历月中断>1 个月的 ART 显著降低了具有不可检测病毒载量的几率[aOR=0.32（95%CI=0.27-0.38）]。与起始基于非核苷逆转录酶抑制剂（NNRTI）的一线方案相比，起始基于蛋白酶抑制剂（PI）的一线方案的患者更不可能具有不可检测的病毒载量[aOR=0.72（95%CI=0.63-0.83）]。
我们的结果表明，1997 年至 2011 年间病毒学结果有显著改善，调整其他因素后仍持续存在。这在一定程度上可能是由于护理和新治疗方案的改进。与基于 NNRTI 的一线方案相比，基于 PI 的一线方案与具有不可检测病毒载量的几率增加有关，这与之前的研究一致。治疗中断被发现是未达到不可检测病毒载量的最重要决定因素。需要研究来描述治疗中断的原因，并制定提高对 ART 依从性的后续策略。
