The influence of low-level viremia on CD4+ cell count in human immunodeficiency virus-infected patients

Following initiation of combined antiretroviral therapy, the majority of human immunodeficiency virus-infected patients experience immune reconstitution indicated by virologic suppression and an increase in peripheral CD4+ T-cell counts. Some patients may suffer from low-level viremia, which was reported to be significantly associated with acquired immunodeficiency syndrome cases, virologic failure, and death. We aimed to further investigate the influence of low-level viremia on CD4+ T-cell count.

In our study, we included human immunodeficiency virus-seropositive patients on combined antiretroviral therapy, for at least 6 months, who received at least one assessment of human immunodeficiency virus plasma viral load and CD4+ cell count every 6 months, from January 2009 to January 2019. The copy-year viremia was determined by calculating the area under the curve of the plasma human immunodeficiency virus viral load.

When comparing patients with a mean CD4+ cell count <200 cells/μL, there was no significant difference between patients with a mean viral load <1000 copies/mL and patients with a mean viral load ≥1000 copies/mL (p = 0.219). Among those with a mean viral load <1000 copies/mL, a higher proportion of patients had a mean CD4+ cell count ≥500 cells/µL (p < 0.001). The mean CD4+ cell count of patients with copy-years viremia (log10) <4 (577.7, interquartile range 429.2-736.7) was significantly higher than that of patients with copy-years viremia (log10) ≥4 (443.3, interquartile range 319.0-558.4) (p < 0.001). In multivariate logistic regression analysis, we observed that malignancy without history, lower copy-years viremia, and high nadir CD4+ cell count were independent predictors of mean CD4+ cell count ≥500 cells/µL.

Human immunodeficiency virus-infected patients with a history of malignancy, high copy-year viremia, and lower nadir CD4+ cell counts should be monitored carefully in clinical settings.