Impaired CD4 + T-cell and CD4 + /CD8 + ratio recovery among people with HIV on antiretroviral therapy.

OBJECTIVE

Antiretroviral therapy (ART) decreases HIV viral replication leading to CD4 + recovery, decreased CD8 + expansion and CD4 + /CD8 + ratio recovery. We investigated factors associated with impaired recovery of CD4 + and CD4 + /CD8 + ratios among people with HIV (PWH) maintaining HIV viral suppression.

DESIGN/

METHODS

PWH at least 18  years old accessing the Southern Alberta Clinic between 01 January 1998 and 01 June 2022 entered the study at time of HIV viral suppression (<200 copies/ml). Continuous time-to-event Cox proportional hazard models estimated crude and adjusted hazards ratios (aHR) and 95% confidence intervals (CIs) for factors associated with recovery of CD4 + count (≥500 cells/μl) and CD4 + /CD8 + ratio (≥1) at 10 years.

RESULTS

Over 10 years, 83% of PWH reached a CD4 + count of at least 500 cells/μl but only 54% reached a CD4 + /CD8 + ratio of ≥1. CD4 + recovery was less common among people diagnosed with HIV older than 50 years vs. younger than 30 years [aHR: 0.59 (0.46-0.77)]. Females were more likely to recover both CD4 + [aHR: 1.42 (1.18-1.71)] and CD4 + /CD8 + ratios [aHR: 1.56 (1.25-1.95)] compared with males. Both higher baseline CD4 + cell counts and CD4 + /CD8 + ratios were associated with greater immune recovery. ART regimen at study entry impacted CD4 + but not CD4 + /CD8 + ratio recovery. Cytomegalovirus (CMV) coinfection was associated with reduced CD4 + /CD8 + ratio recovery [aHR: 0.47 (0.37-0.62)].

CONCLUSION

While most PWH with ongoing viral suppression will recover their CD4 + cell counts, recovery of CD4 + /CD8 + ratio recovery is less common, indicating ongoing immune dysfunction. Several demographic and clinical factors are associated with impaired immune recovery. Further characterization and understanding of the long-term impact of impaired immune recovery is needed.