HIV disease progression in a patient cohort treated via a clinical research network in a resource limited setting

To examine HIV disease progression in a cohort of adult patients treated with antiretroviral therapy (ART) via a clinical research network in Thailand.

A cohort of 417 patients enrolled in a series of randomized ART trials, between 1996 and December 2002.

Progression to combined endpoint of AIDS defining illness or death according to baseline characteristics, ART used, immunological and virological responses to initial 6 months of ART.

During 1677 person years of follow-up, 29 of 417 patients progressed; tuberculosis was the most common event defining progression (14 of 29 events). The rates of progression to combined endpoint or death alone were 1.7 [95% confidence interval (CI), 1.1-2.4] and 0.7 (95% CI, 0.3-1.3) per 10 person years respectively. Compared to patients with baseline CD4 cell counts > or =350 x 10/l, the adjusted hazard ratio (HR) for progression was 3.67 (95% CI, 1.31-10.27) for patients with <200 x 10 cells/l. Responses to 6 months of therapy were the strongest predictors of disease progression; compared to patients with undetectable viral load at 6 months, HR for progression was 4.95 (95% CI, 2.14-11.46) for viral load >4 log10. Compared to patients with a 6-month CD4 cell count > or =350 x 10/l, HR for progression was 5.22 (95% CI, 1.90-14.37) for patients with <200 x 10 cells/l.

HIV-infected patients in Thailand who had access to ART, appropriate care, CD4 cell and viral load monitoring facilities via a clinical research network had progression rates comparable to those in developed countries. In this setting, ART initiation could generally be delayed until the CD4 cell count approaches 200 x 10/l.