Demographic and clinical factors correlated with clinical outcomes among people with HIV treated by antiretroviral therapy: a retrospective cohort study

Abstract

Background: As is known, CD4 cell count is a significant parameter predicting HIV progression, opportunistic infections and death in HIV-infected individuals, as well was an important indicator for initiating antiretroviral therapy (ART). In China's National Free Antiretroviral Treatment Program, people with HIV (PWH) on ART can receive a CD4 count test at least once every six months. Importantly, the baseline CD4 count (before ART initiation) is significantly correlated with ART and even prognosis, but the influence of the peak CD4 cell count on ART and/or clinical outcomes is still unknown.

Methods: A retrospective study was conducted among 7965 PWH who received ART from October 2003 to September 2022 at Yunnan Infectious Disease Hospital. Clinical features and laboratory data were collected and analyzed by Chi-square test, univariate and multivariate Cox regression analysis. After elimination of confounding variables, multivariate Cox regression analysis was performed to identify survival-related factors.

Results: Of a total of 7965 PWH in the ART treatment cohort who met the inclusion and exclusion criteria, 7939 were finally included in the subsequent analyses. First, it was found that the proportion of clinical variables, including sex, age distribution, interval from diagnosis to ART initiation, marital status, and others, was significantly different between the living and dead groups (P < 0.05). Impressively, significantly more PWH had the higher level of baseline, peak and recent CD4 cell counts in the living group compared to those in the dead group. Due to multicollinearity effect, after excluding confounders, the following factors were found to be significantly associated with mortality by multivariate Cox regression analysis: (1) male sex (hazard ratio (HR) = 1.268 [1.032, 1.559]; P = 0.024); (2) time from HIV confirmation to ART initiation ≥ 6 months (HR = 1.962 [1.631, 2.360]; P < 0.001); (3) peak CD4 cell count: Peak CD4 < 100cells/µL group (HR = 16.093 [12.041, 21.508]; P < 0.001), 100cells/µL ≤ x < 200cells/µL group (HR = 7.904 [6.148, 10.160]; P < 0.001), 200cells/µL ≤ x < 350cells/µL group (HR = 3.166 [2.519, 3.980]; P < 0.001), 350cells/µL ≤ x < 500cells/µL group (HR = 1.668 [1.291, 2.155]; P < 0.001).

Conclusion: Interestingly, patients in male, time from HIV confirmation to ART initiation ≥ 6 months, or peak CD4 count < 500 cells/µl had inferior clinical outcomes, in other word, a lower peak CD4 cell count significantly increased the risk of death, and peak CD4 cell was independent in predicting the overall survival of PWH. It is important to promote "early diagnosis and treatment of HIV" and regularly monitor CD4 levels in HIV/AIDS to evaluate the efficacy of ART and immune reconstitution, and optimize the ART regimen in time to further reduce the mortality of PWH.

Keywords: AIDS; Antiretroviral therapy; HIV; Hazard ratio; Peak CD4.