Association between HIV low-level viremia and CD4+ cell count changes among people living with HIV during antiretroviral therapy in Dehong, Southwest China in 2008-2021: a longitudinal study

Abstract Background The impact of human immunodeficiency virus (HIV) low-level viremia (LLV) on CD4 + T lymphocyte (CD4) cell count during antiretroviral therapy (ART) remains unknown in China. We aimed to investigate the association between LLV and changes in CD4 cell count among adults on ART in Southwest China. Methods A longitudinal cohort study on people living with HIV (PLWH) were conducted in Dehong Prefecture, Southwest China, with viral load (VL) and CD4 cell count measured yearly. The proportion of LLV with VL of 50–999 copies/ml was described. The incidences of CD4 cell count ≥ 500 cells/µl was calculated by follow-up years. The CD4 cell count and LLV trajectories were classified with group-based trajectory model (GBTM). Associations between LLV and CD4 cell count < 500 cells/µl were analyzed using a generalized estimating equation (GEE) with follow-up LLV as a time-updated variable. Results We followed the longitudinal cohort of 7,485 PLWH (median observation time, 8.5 years) from 2008 to 2021 in Dehong. The median age at ART baseline was 36 years and male participants accounted for 60.5%. The median CD4 cell count at baseline was 268 cells/µl. Seven hundred and thirty patients (9.8%) experience continuous LLV trajectories and only 2,125 patients (28.4%) reached CD4 cell count > 500 cells/µl level using GBTM. The risk of CD4 cell count < 500 cells/µl were high for participants with LLV 50–199 copies/ml (adjusted odds ratio [aOR] 1.1, 95% confidence interval [CI] 1.0-1.3) and LLV 200–999 copies/ml (aOR 1.3, 95% CI 1.1–1.5), compared with participants with VL < 50 copies/ml. Conclusion LLV during ART follow-ups is associated with an increased risk of poor CD4 recovery among HIV patients. LLV monitoring and intervention should be strengthened.