Acute HIV Infection and CD4/CD8 Ratio Normalization After Antiretroviral Therapy Initiation

Area of Science:

• Immunology
• Virology
• Infectious Diseases

Background:

• The CD4/CD8 ratio is a key indicator of immune function in HIV.
• Initiating antiretroviral therapy (ART) during acute HIV infection (AHI) may impact immune recovery differently than during chronic HIV infection (CHI).

Purpose of the Study:

• To estimate the effect of initiating ART during AHI versus CHI on CD4/CD8 ratio normalization.
• To compare the time to CD4/CD8 ratio normalization between patients with AHI and CHI.

Main Methods:

• Prospective cohort study of 1198 patients initiating ART between 2000-2015.
• Kaplan-Meier curves and multivariable Cox proportional hazards models used to compare time to normalization (CD4/CD8 ratio ≥1).
• CD4, CD8, and CD4/CD8 trajectories analyzed over 3 years of ART.

Main Results:

• 70% of AHI patients achieved a normal CD4/CD8 ratio within 2 years, versus 6%-38% of CHI patients.
• Time to normalization was shortest in AHI patients, followed by CHI patients with higher baseline CD4 counts.
• Initiating ART during AHI was associated with a 4.33-fold increased likelihood of normalization compared to CHI (baseline CD4 >350).

Conclusions:

• Initiating ART during acute HIV infection is associated with faster CD4/CD8 ratio normalization.
• Higher baseline CD4 cell counts and CD4/CD8 ratios further shorten the time to normalization in AHI.
• Early ART initiation is crucial for immune recovery in HIV.