To determine the clinical and immunological outcomes of a cohort of HIV-infected patients receiving antiretroviral therapy. Retrospective study of prospectively collected data from consecutively enrolled adult HIV-infected patients in eight HIV clinics in western Kenya. CD4 cell counts, weight, mortality, loss to follow-up and adherence to antiretroviral therapy were collected for the 2059 HIV-positive non-pregnant adult patients treated with antiretroviral drugs between November 2001 and February 2005. Median duration of follow-up after initiation of antiretroviral therapy was 40 weeks (95% confidence interval, 38-43); 111 patients (5.4%) were documented as deceased and 505 (24.5%) were lost to follow-up. Among 1766 (86%) evaluated for adherence to their antiretroviral regimen, 78% reported perfect adherence at every visit. Although patients with and without perfect adherence gained weight, patients with less than perfect adherence gained 1.04 kg less weight than those reporting perfect adherence (P = 0.059). CD4 cell counts increased by a mean of 109 cells/microl during the first 6 weeks of therapy and increased more slowly thereafter, resulting in overall CD4 cell count increases of 160, 225 and 297 cells/microl at 12, 24, and 36 months respectively. At 1 year, a mean increase of 170 cells/microl was seen among patients reporting perfect adherence compared with 123 cells/microl among those reporting some missed doses (P < 0.001). Antiretroviral treatment of adult Kenyans in this cohort resulted in significant and persistent clinical and immunological benefit. These findings document the viability and effectiveness of large-scale HIV treatment initiatives in resource-limited settings.
