Immune recovery among HIV-infected patients in northwestern Tanzania after 2 years of anti-retroviral therapy use: a retrospective cohort study

Abstract

Background: The use of antiretroviral therapy (ART) for the treatment of human immunodeficiency virus (HIV) is associated with significant and sustained decrease in the viral RNA levels that allows the immune system to recover. The extent of this immune recovery depends on the baseline CD4 count. Evidence on the extent of immune recovery in patients with advanced HIV from resource limited settings is scarce. The objective of this study was to determine immune recovery in a cohort of HIV infected outpatients after using ART for a period of 2 years.

Methods: This retrospective cohort study was conducted in an outpatient HIV clinic at Bugando Medical Centre in northwestern Tanzania. CD4+ T-cell counts for HIV-positive adults at the time of enrolment were measured and retrospectively followed up during ART eligibility screening process prior to initiation of antiretroviral (ARV) drugs. We then compared the CD4+ T-cell counts at baseline and that during the enrolment.

Results: A total of 238 patients files were screened for enrolment. Of the 238 patients, 171 (71.8%) fulfilled the criteria and were enrolled for the study. The lack of participation was due to death 17 (7.1%), lost to follow-up 32 (13.4%) and refusal 18 (9.5%). Of the 171 patients, the median CD4 count at the time of ART initiation was 153 cells/µl [Interquartile range (IQR): 78 – 199], 164 (95.9%) had increased their CD4 cells count, with 74.3% having an increase of more than 150 cells/µl. Only 8 (4.7%) patients had a decline of CD4 cell count. The median CD4 cells count after a 2-year follow up was significantly higher (396 [IQR: 295 – 567]) than at baseline (153 [IQR: 78 – 199]) cells/ul; p-value <0.0001).

Conclusion: The CD4 cells count increased significantly after a follow up period of 2 years after ART use in this cohort. Early diagnosis and ART initiation could therefore improve outcomes in HIV-infected patients in resource limited settings.