Does most early mortality in patients on ART occur in care or lost to follow-up? Evidence from the Themba Lethu Clinic, South Africa

Abstract

Objective: In resource-limited settings, early mortality on antiretroviral therapy (ART) is about 10% yet it is unclear how much of that mortality occurs in care or among patients lost to follow-up. Methods: We assessed mortality rates among non-pregnant ART-naïve adults initiating first-line ART between April 2004–May 2012 in South Africa, stratified by person-years (py) in care and lost. Deaths were ascertained from the National Population Register and multiple definitions of loss were analysed. Results: 12,222 patients initiated ART; 38.1% were male, median age was 37.2 years (IQR: 31.8-43.8), and median CD4 count was 98 cells/mm³ (IQR: 37-177). Patients were followed for 43,378 py (median 3.2 py, IQR 1.4–5.5) during which time 14.6% (1,784/12,222) died. With loss defined as ≥3 months late for a scheduled visit, nearly 76% (1,350/1,784) of deaths occurred in care. However, in adjusted analyses, individuals lost had twice the mortality of those in care (HR: 2.05; 1.81–2.31). As the definition of loss was varied from ≥1 day late to ≥6 months late we found a shrinking minority of overall deaths could be attributed to loss from ART care (population attributable risk decreased from 43% to 10%). Mortality in patients lost (range: 79-128 deaths/1,000 py) remained much higher than in patients in care (range: 24-37 deaths/1,000 py) across all definitions of loss. Conclusion: Our findings suggest that while mortality rates in patients lost are much higher than in care, most ART-related mortality occurs on treatment.

Conference: International AIDS conference 2014, Melbourne, Australia