Antiretroviral Therapy Within 2 Years of HIV Acquisition Is Associated With Fewer Viral Blips: A Retrospective Analysis of More Than 20 Years of Data From the US Military HIV Natural History Study.

Abstract

Background: Viral blips have been associated with larger reservoir size and slower decay. Earlier antiretroviral therapy (ART) initiation may decrease the risk of blips.

Methods: We analyzed participants from the US Military HIV Natural History Study with an estimated human immunodeficiency virus (HIV) seroconversion date, viral suppression ≤400 copies/mL within 1 year after starting ART, and at least 3 HIV RNA measurements after suppression. A blip was defined as HIV RNA 401-1000 copies/mL preceded and followed by HIV RNA ≤400 copies/mL without changing ART. Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for factors potentially associated with the time from viral suppression to first blip.

Results: From 1996 through 2022, among 1413 participants on stable suppressive ART, 88 (6.2%) had at least one blip, including 68 (77.3%) with only a single blip. The overall incidence was 1.2 blips per 100 person-years (95% CI: .9-1.4). In multivariable modeling, ART initiation within 24 months of estimated HIV acquisition was independently associated with decreased hazard of viral blips compared with ART initiation after more than 24 months (0-6 months HR: 0.29 and 95% CI: .18-.48; 6-12 months HR: 0.43 and 95% CI: .31-.59; 12-24 months HR: 0.46 and 95% CI: .35-.60).

Conclusions: Participants who initiated ART within 2 years of HIV acquisition had lower hazard of blips, potentially reflecting smaller reservoir size and suggesting reservoir plasticity that extends beyond the acute phase of HIV.