Second-line antiretroviral therapy in a workplace and community-based treatment programme in South Africa: determinants of virological outcome

PLoS One. 2012;7(5):e36997. doi: 10.1371/journal.pone.0036997. Epub 2012 May 29.

Abstract

Background: As antiretroviral treatment (ART) programmes in resource-limited settings mature, more patients are experiencing virological failure. Without resistance testing, deciding who should switch to second-line ART can be difficult. The consequences for second-line outcomes are unclear. In a workplace- and community-based multi-site programme, with 6-monthly virological monitoring, we describe outcomes and predictors of viral suppression on second-line, protease inhibitor-based ART.

Methods: We used prospectively collected clinic data from patients commencing first-line ART between 1/1/03 and 31/12/08 to construct a study cohort of patients switched to second-line ART in the presence of a viral load (VL) ≥ 400 copies/ml. Predictors of VL<400 copies/ml within 15 months of switch were assessed using modified Poisson regression to estimate risk ratios.

Results: 205 workplace patients (91.7% male; median age 43 yrs) and 212 community patients (38.7% male; median age 36 yrs) switched regimens. At switch compared to community patients, workplace patients had a longer duration of viraemia, higher VL, lower CD4 count, and higher reported non-adherence on first-line ART. Non-adherence was the reported reason for switching in a higher proportion of workplace patients. Following switch, 48.3% (workplace) and 72.0% (community) achieved VL<400, with non-adherence (17.9% vs. 1.4%) and virological rebound (35.6% vs. 13.2% with available measures) reported more commonly in the workplace programme. In adjusted analysis of the workplace programme, lower switch VL and younger age were associated with VL<400. In the community programme, shorter duration of viraemia, higher CD4 count and transfers into programme on ART were associated with VL<400.

Conclusion: High levels of viral suppression on second-line ART can be, but are not always, achieved in multi-site treatment programmes with both individual- and programme-level factors influencing outcomes. Strategies to support both healthcare workers and patients during this switch period need to be evaluated; sub-optimal adherence, particularly in the workplace programme must be addressed.

Publication types

  • Clinical Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Anti-HIV Agents / pharmacology*
  • Female
  • HIV / drug effects*
  • HIV / physiology
  • Humans
  • Male
  • Middle Aged
  • Patient Compliance / statistics & numerical data
  • Residence Characteristics / statistics & numerical data*
  • South Africa
  • Treatment Outcome
  • Viral Load / drug effects
  • Withholding Treatment / statistics & numerical data
  • Workplace / statistics & numerical data

Substances

  • Anti-HIV Agents