Pregnancy and virologic response to antiretroviral therapy in South Africa.

Although women of reproductive age are the largest group of HIV-infected individuals in sub-Saharan Africa, little is known about the impact of pregnancy on response to highly active antiretroviral therapy (HAART) in that setting. We examined the effect of incident pregnancy after HAART initiation on virologic response to HAART. We evaluated a prospective clinical cohort of adult women who initiated HAART in Johannesburg, South Africa between 1 April 2004 and 30 September 2009, and followed up until an event, death, transfer, drop-out, or administrative end of follow-up on 31 March 2010. Women over age 45 and women who were pregnant at HAART initiation were excluded from the study; final sample size for analysis was 5,494 women. Main exposure was incident pregnancy, experienced by 541 women; main outcome was virologic failure, defined as a failure to suppress virus to ≤400 copies/ml by six months or virologic rebound >400 copies/ml thereafter. We calculated adjusted hazard ratios using marginal structural Cox proportional hazards models and weighted lifetable analysis to calculate adjusted five-year risk differences. The weighted hazard ratio for the effect of pregnancy on time to virologic failure was 1.34 (95% confidence limit [CL] 1.02, 1.78). Sensitivity analyses generally confirmed these main results. Incident pregnancy after HAART initiation was associated with modest increases in both relative and absolute risks of virologic failure, although uncontrolled confounding cannot be ruled out. Nonetheless, these results reinforce that family planning is an essential part of care for HIV-positive women in sub-Saharan Africa. More work is needed to confirm these findings and to explore specific etiologic pathways by which such effects may operate.

尽管育龄女性是撒哈拉以南非洲感染艾滋病毒人数最多的群体，但在该地区，怀孕对高效抗逆转录病毒疗法（HAART）治疗反应的影响却鲜为人知。我们研究了开始HAART治疗后意外怀孕对HAART病毒学应答的影响。 我们评估了一个前瞻性临床队列，队列中的成年女性于2004年4月1日至2009年9月30日在南非约翰内斯堡开始接受HAART治疗，并随访至2010年3月31日出现事件、死亡、转院、失访或行政随访结束。45岁以上的女性以及在开始HAART治疗时已怀孕的女性被排除在研究之外；用于分析的最终样本量为5494名女性。主要暴露因素是意外怀孕，有541名女性经历了意外怀孕；主要结局是病毒学失败，定义为在6个月时未能将病毒抑制到≤400拷贝/毫升，或此后病毒学反弹＞400拷贝/毫升。我们使用边际结构Cox比例风险模型计算调整后的风险比，并通过加权寿命表分析计算调整后的5年风险差异。怀孕对病毒学失败时间影响的加权风险比为1.34（95%置信区间[CL]为1.02 - 1.78）。敏感性分析基本证实了这些主要结果。 开始HAART治疗后的意外怀孕与病毒学失败的相对风险和绝对风险的适度增加有关，尽管不能排除未控制的混杂因素。尽管如此，这些结果强调了计划生育是撒哈拉以南非洲艾滋病毒阳性女性护理的重要组成部分。需要更多的工作来证实这些发现，并探索这种影响可能起作用的具体病因途径。