Changes in cardiovascular disease risk factors with immediate versus deferred antiretroviral therapy initiation among HIV-positive participants in the START (Strategic Timing of Antiretroviral Treatment) trial. Journal of the American Heart Association
The START trial is a randomized controlled study of immediate initiation of antiretroviral therapy (ART) (“immediate” group) versus deferral of ART initiation until CD4+ cell counts decline to 3 or clinical symptoms develop (“deferred” group) among participants naive to ART with CD4+ cell counts >500 cells/mm3 at entry.
Baker et al. on behalf of the START trial study-group characterized the influence of immediate versus deferred ART on cardiovascular disease (CVD) risk factor changes and incidence of CVD-related comorbidities.
The characteristics among 4’685 HIV-positive START trial participants included a median age of 36 years, a CD4 cell count of 651 cells/mm3, an HIV viral load of 12’759 copies/mL, and a current smoking status of 32%. Mean follow-up was 3.0 years. The immediate and deferred ART groups spent 94% and 28% of follow-up time taking ART, respectively. Compared with patients in the deferral group, patients in the immediate ART group had increased total cholesterol and low-density lipoprotein cholesterol and higher use of lipid-lowering therapy (1.2%). Concurrent increases in high-density lipoprotein cholesterol with immediate ART resulted in a 0.1 lower total cholesterol to high-density lipoprotein cholesterol ratio. Immediate ART resulted in 2.3% less blood pressure-lowering therapy use but there were no differences in new-onset hypertension or diabetes mellitus.
In conclusion, these data suggest that immediate ART initiation has both positive and negative influences on CVD risk factors. Changes in CVD or coronary heart disease prediction scores with immediate versus deferred ART were minimal or nonsignificant. The opposing effects of immediate ART initiation suggest that, in the short term, the net effect of early ART on traditional cardiovascular disease risk factors may be clinically insignificant. Ultimately, long-term follow-up in the START trial is needed to determine the net effect of ART treatment initiation for CVD event risk among HIV-positive individuals with preserved immunity.