It is unclear how adherence to highly active antiretroviral therapy (HAART) may best be monitored in large HIV programs in sub-Saharan Africa where it is being scaled up. We aimed to evaluate the association between HAART adherence, as estimated by pharmacy claims, and survival in HIV-1-infected South African adults enrolled in a private-sector AIDS management program. Of the 6288 patients who began HAART between January 1999 and August 2004, 3805 (61%) were female and 6094 (97%) were black African. HAART adherence was ≥80% for 3298 patients (52%) and 100% for 1916 patients (30%). Women were significantly more likely to have adherence ≥80% than men (54% vs 49%, P < 0.001). The median (interquartile range) follow-up time was 1.8 (1.37-2.5) years. As of 1 September 2004, 222 patients had died-a crude mortality rate of 3.5%. In a multivariate Cox regression model, adherence <80% was associated with lower survival (relative hazard 3.23; 95% confidence interval: 2.37-4.39). When medication adherence was divided into 5 strata with a width of 20% each, each stratum had lower survival rates than the adjacent, higher-adherence stratum. Among other variables tested, only baseline CD4+ T-cell count was significantly associated with decreased survival in multivariate analysis (relative hazard 5.13; 95% confidence interval: 3.42-7.72, for CD4+ T-cell count ≤50 cells/μL vs >200 cells/μL). Pharmacy-based records may be a simple and effective population-level tool for monitoring adherence as HAART programs in Africa are scaled up.
From the Departments of *International Health and ‡Epidemiology, Johns Hopkins University, Bloomberg School of Public Health; §Department of Medicine, Division of Infectious Diseases, Johns Hopkins University, School of Medicine, Baltimore, MD; †Aid for AIDS Disease Management Programme (Pty) Ltd, Cape Town, South Africa; and the ∥Department of Medicine, Division of Clinical Pharmacology, University of Cape Town, Cape Town, South Africa.
Received for publication December 18, 2005; accepted April 17, 2006.
Drs J. Nachega, R.E. Chaisson, and G. Maartens acknowledge research support from the US National Institutes of Health, AI 5535901 and AI 016137. Dr J. Nachega is recipient of an NIH Mentored-Patient Oriented Research Career Award K23 AI068582-01. The funders had no input on the results or presentation of the results reported in the present article.
Presented as an oral presentation at the 12th Conference on Retroviruses and Opportunistic Infections, February 22 to 25, 2005, Boston, MA (WedsOrAb#25).
Reprints: Jean B. Nachega, MD, MPH, Department of International Health, Johns Hopkins University, Bloomberg School of Public Health, 615 N. Wolfe St, Suite W5031, Baltimore, MD 21205. E-mail: email@example.com.