Objective: to determine adherence of an indigent African HIV-infected cohort initiating antiretroviral therapy (ART); to identify predictors of incomplete adherence (< 95%) and virologic failure (> 400 HIV RNA copies/ml).
Design: Prospective monitoring of adherence in a poor HIV-positive cohort, attending a public sector hospital and receiving ART through phase III studies.
Methods: Adherence to ART was determined over 48 weeks by counting tablet-returns. Logistic regression models including age, WHO HIV stage, home language, socio-economic status, complexity and type of regimen were fitted to determine predictors of incomplete adherence and virologic failure at 48 weeks.
Results: 289 patients were recruited between January 1996 and May 2001. Median (mean) adherence of the cohort was 93.5% (87.2%). Three times daily dosing [risk ratio (RR), 3.07; 95% confidence interval (CI), 1.40–6.74], speaking English (RR, 0.41; 95% CI, 0.21–0.80) and age (RR, 0.97; 95% CI, 0.94–0.99) were independent predictors of incomplete adherence. Socio-economic status, sex and HIV stage did not predict adherence. Independent predictors of virologic failure included baseline viral load (RR, 2.57; 95% CI, 1.57–4.22) and three times daily dosing (RR, 2.64; 95% CI, 1.23–5.66), incomplete adherence (RR, 1.92; 95% CI, 1.10–3.57), age (RR, 0.96; 95% CI, 0.92–0.99) and dual nucleoside therapy (RR, 2.69; 95% CI, 1.17–6.15).
Conclusion: The proportion of individuals achieving viral suppression matched results from the developing world. Speaking the same language as site staff and simplified dosing frequency were beneficial. Socio-economic status had no impact on adherence and should not be used as a limitation to ART access.
From the Diana, Princess of Wales HIV Research Unit, Somerset Hospital, University of Cape Town, South Africa, and the aEpidemiology and Prevention Interventions Centre, Division of Infectious Diseases and the Positive Health Program, UCSF, San Francisco, California, USA.
Correspondence to C. Orrell, Diana, Princess of Wales HIV Research Unit, PO Box 50309, V & A Waterfront, Cape Town, South Africa, 8005.
Note: Presented in part at the International AIDS Society Conference, Buenos Aires, July 2001 [abstract 696] and at the XIV International Conference on AIDS, Barcelona, July 2002 [abstract WePeB5816].
Received: 16 August 2003; revised: 20 December 2003; accepted: 22 January 2003.