Pregnancy and virologic response to antiretroviral therapy in South Africa.

Landon Myer,Daniel Westreich,Stephen R Cole,Charles Van Der Horst,Mhairi Maskew,Shashi Nagar,Ian Sanne

doi:10.1371/journal.pone.0022778

Abstract

BackgroundAlthough 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.Methods and FindingsWe 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.ConclusionsIncident 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.

Highlights

The largest group of individuals living with HIV in Africa are women of child-bearing age [1]
Incident pregnancy after highly active antiretroviral therapy (HAART) initiation was associated with modest increases in both relative and absolute risks of virologic failure, uncontrolled confounding cannot be ruled out
In South Africa, antenatal testing is a key way in which women receive an HIV diagnosis; as such, pregnancy is a common indication for the initiation of highly active antiretroviral therapy (HAART) for the prevention of mother to child transmission [4]

Summary

Introduction

The largest group of individuals living with HIV in Africa are women of child-bearing age [1]. In South Africa, antenatal testing is a key way in which women receive an HIV diagnosis; as such, pregnancy is a common indication for the initiation of highly active antiretroviral therapy (HAART) for the prevention of mother to child transmission [4]. To date there has been very little research examining effects of pregnancy on maternal response to HAART in sub-Saharan Africa [25]. This relative absence of evidence is striking given the unequivocal statement by the WHO that women’s health should be ‘‘the overarching priority in decisions about ARV treatment during pregnancy’’ [26]. 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

Methods

Results

Discussion

Conclusion