CD4 + T-cell recovery after initiation of antiretroviral therapy in a resource-limited setting: A prospective cohort analysis

Abstract

Background

CD4⁺ T-cell count recovery after antiretroviral therapy (ART) initiation is associated with improved health outcomes. It is unknown how the CD4⁺ T-cell counts of African HIV patients recover following ART initiation.

Methods

We examined CD4⁺ T-cell count recovery in a large cohort of HIV-positive patients initiating ART in Uganda between 2004 and 2011. We categorized patients according to their CD4⁺ T-cell count at ART initiation. All patients received CD4⁺ T-cell count evaluations on a biannual basis. We used quantile regression to model the recovery of CD4⁺ T-cells during ART.

Results

A total of 5,271 patients aged ≥14 years at baseline were included. The median number of CD4⁺ T-cell count measurements was 6 (IQR 4–8), and vital status at censoring was known in 97.2% of individuals. Most CD4⁺ T-cell count recovery occurred within the first 12 months, with marginal increases beyond 18 months and stabilization after 5 years. The strongest predictor of CD4⁺ T-cell count recovery was baseline CD4⁺ T-cell count. After 5 years on treatment, the median CD4⁺ T-cell count was 334 cells/mm³ for patients initiating ART with <100 cells/mm³. Only those initiating ART with >200 cells/mm³ reached a 5-year median >500 cells/mm³. Adolescents had the most robust CD4⁺ T-cell count recovery with a median increase after 12 months that was 109 cells/mm³ greater than those initiating ART at age ≥50 years.

Conclusions

In individuals from a resource-limited setting, baseline CD4⁺ T-cell count was highly predictive of the maximum CD4⁺ T-cell count level achieved while on ART.

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