Modification of antiretroviral therapy in HIV-infected patients at the Kenyatta National Hospital Comprehensive Care Clinic between years 2005-2011

Abstract

Background: The initial ART regimen is widely considered to be the most important regimen in HIV treatment because it is associated with the greatest probability of achieving sustained ! virologic response. Modification from the initial ART regimen results in a lower probability of virologic suppression and frequent modifications may exhaust future options for effective treatment. Objective: To determine the proportion of, reasons for, duration of initial ART modification among HIV patients at Kenyatta National Hospital (KNH) HIV I AIDS Outpatient Clinic. Design: A retrospective cross-sectional clinical record review. Methods: All patients who commenced ART from January 2005 to June 2011 and had at least 1 follow-up visit were evaluated. We recorded baseline and follow-up data, including drug prescriptions and reasons for changing to alternative first-line regimens (drug substitution for any reason but failure) or second-line regimens (switch for failure). Results: Out of 4820 patients 1775 patients modified their initial ART at a rate of 36.8% (95% confidence interval [CI] 35.4-38.2%). The median CD4+ count at initiating ART was 149cells/ml (IQR 55-248). The most common first-line regimens were stavudine (d4t) and zidovudine (AZT) based at 63% and 13.3% respectively. The commonest reasons for modifying ART were toxicity accounting for 66.5%, treatment failure 12.9%, and co-morbid conditions 9.4%. The most frequent toxic effects were lipodystrophy (41.3%). peripheral neuropathy (10.6%) and anemia (5.9%). The median time to modifying therapy was 28 months (IQR 15-41). Immunological outcome of modification pre and post-modification was 335cells/ml (IQR 8-497) to 399cells/ml (IQR 257-611) with p=O.OO1. In the multivariate analysis WHO clinical stage III (odds ratio [OR], 2.9 [95%CI 1.7-2.8]; p=0.001), and IV (5.5 [2.8-11.0]; p=0.001), CD4+ count ::; 200cells/ml (2.4 [1.5-4.0]; p=0.001) were associated with likelihood of modifying ART. Conclusion: There was a high rate of ART modification in this study. Drug toxicity was the most frequent reason for treatment modification; however it did not affect treatment success. The median duration to modification of first-line ART was 28 months. Low CD4+ count, increasing WHO stage and longerduration of ART was associated with likelihood of ART modification,