Initiating patients on antiretroviral therapy at CD4 cell counts above 200 cells/microl is associated with improved treatment outcomes in South Africa.

OBJECTIVES

To compare treatment outcomes by starting CD4 cell counts using data from the Comprehensive International Program of Research on AIDS-South Africa trial.

DESIGN

An observational cohort study.

METHODS

Patients presenting to primary care clinics with CD4 cell counts below 350 cells/microl were randomized to either doctor or nurse-managed HIV care and followed for at least 2 years after antiretroviral therapy (ART) initiation. Clinical and laboratory outcomes were compared by baseline CD4 cell counts.

RESULTS

Eight hundred and twelve patients were followed for a median of 27.5 months and 36% initiated ART with a CD4 cell count above 200 cells/microl. Although 10% of patients failed virologically, the risk was nearly double among those with a CD4 cell count of 200 cells/microl or less vs. above 200 cells/microl (12.2 vs. 6.8%). Twenty-one deaths occurred, with a five-fold increased risk for the low CD4 cell count group (3.7 vs. 0.7%). After adjustment, those with a CD4 cell count of 200 cells/microl had twice the risk of death/virologic failure [hazard ratio 1.9; 95% confidence interval (CI), 1.1-3.3] and twice the risk of incident tuberculosis (hazard ratio 1.90; 95% CI, 0.89-4.04) as those above 200 cells/microl. Those with either a CD4 cell count of 200 cells/microl or less (hazard ratio 2.1; 95% CI, 1.2-3.8) or a WHO IV condition (hazard ratio 2.9; 95% CI, 0.93-8.8) alone had a two-to-three-fold increased risk of death/virologic failure vs. those with neither, but those with both conditions had a four-fold increased risk (hazard ratio 3.9; 95% CI, 1.9-8.1). We observed some decreased loss to follow-up among those initiating ART at less than 200 cells/microl (hazard ratio 0.79; 95% CI, 0.50-1.25).

CONCLUSION

Patients initiating ART with higher CD4 cell counts had reduced mortality, tuberculosis and less virologic failure than those initiated at lower CD4 cell counts. Our data support increasing CD4 cell count eligibility criteria for ART initiation.