Background: Due to toxicities associated with the NRTI stavudine, many countries now recommend initiating HIV patients on tenofovir as the standard NRTI in first-line therapy. Exploiting national guideline changes in South Africa and Zambia, we assessed the causal impact of a policy to initiate tenofovir on ART outcomes using a regression discontinuity design. Objectives: To establish the causal effect of tenofovir (vs. stavudine) on patient outcomes in South Africa and Zambia’s public sector HIV clinics. Methods: STUDY POPULATION: Prospective cohort study of ART-naïve, non-pregnant, HIV patients >16 years old who initiated first-line ART in South Africa or Zambia (IeDEA-SA cohort). Patients were included if they initiated ART +/-12 months around the national guideline changes: 1 April 2010 in South Africa and 1 July 2007 in Zambia. All patients had the potential for 24-months of follow-up. OUTCOMES: Indicator for death, loss to follow-up (defined as not attending the clinic in at least 6-months), single-drug substitution (changing NRTI within first-line ART), immunological and virologic failure (defined as two consecutive viral loads >400 copies/mL) in the first 24-months on ART.
Conference: IWHOD 2015, Catania, Sicily, 26-28 March 2015