Anti-Retroviral Treatment Outcomes among Older Adults in Zomba District, Malawi

Background: There are approximately 3 million people aged 50 and older in sub-Saharan Africa who are HIV-positive. Despite this, little is known about the characteristics of older adults who are on treatment and their treatment outcomes. Methods: A retrospective cohort analysis was performed using routinely collected data with Malawi Ministry of Health monitoring tools from facilities providing antiretroviral therapy services in Zomba district. Patients aged 25 years and older initiated on treatment from July 2005 to June 2010 were included. Differences in survival, by age group, were determined using Kaplan-Meier survival plots and Cox proportional hazards regression models. Results: There were 10,888 patients aged 25 and older. Patients aged 50 and older (N = 1419) were more likely to be male (P < 0.0001) and located in rural areas (P = 0.003) than those aged 25-49. Crude survival estimates among those aged 50-59 were not statistically different from those aged 25-49 (P = 0.925). However, survival among those aged 60 and older (N = 345) was worse (P = 0.019) than among those 25-59. In the proportional hazards model, after controlling for sex and stage at initiation, survival in those aged 50-59 did not differ significantly from those aged 25-49 (hazard ratio 1.00 (95% CI: 0.79 to 1.27; P = 0.998) but the hazard ratio was 1.46 (95% CI: 1.03 to 2.06; P = 0.032) for those aged 60 and older compared to those aged 25-49. Conclusions: Treatment outcomes of those aged 50-59 are similar to those aged 25-49. A better understanding of how older adults present for and respond to treatment is critical to improving HIV services.