Subclinical cardiovascular disease in patients starting contemporary protease inhibitors

The aim of the study was to assess changes in and factors associated with anatomical [carotid artery intima-media thickness (CIMT)] and functional (arterial stiffness) markers of subclinical cardiovascular disease progression in antiretroviral-naïve patients starting triple combination antiretroviral therapy containing contemporary protease inhibitors.

This was a planned substudy of the ATADAR (Metabolic Effects of Atazanavir/Ritonavir Versus Darunavir/Ritonavir in Combination With Tenofovir/Emtricitabine in naïve HIV-1 Infected Patients) clinical trial (ClinicalTrials.gov identifier NCT01274780). ATADAR is a multicentre, randomized, open-label clinical trial comparing the effects of ritonavir-boosted atazanavir and darunavir, both with tenofovir/emtricitabine, in antiretroviral-naïve HIV-infected patients. Common CIMT and aortic augmentation index (AIx@75) were measured at baseline and after 12 months of follow-up. Antiretroviral treatment, traditional cardiovascular risk factors and HIV-related factors were assessed as potential predictors of CIMT and Aix@75 changes using linear regression analysis.

Thirty-three patients were included in this pilot study. While CIMT significantly increased in the pooled population [median (interquartile range (IQR)) 68 (-13, 128) μm; P = 0.0511], AIx@75 did not [median (IQR) 1 (-6, 5)%; P = 0.8964]. Patients on darunavir showed a trend to faster CIMT progression than those on atazanavir [median change (IQR) 117 (-2, 143) vs. -6 (-58, 89) μm, respectively; P = 0.0917]. However, after adjustment in the multivariate analysis, a higher baseline Framingham score was the only factor associated with CIMT progression (coefficient 16.02; 95% confidence interval -1.04, 33.08; P = 0.064). AIx@75 change was not associated with any baseline factor.

CIMT was a more sensitive marker of subclinical vascular disease progression than arterial stiffness in antiretroviral-naïve patients starting antiretroviral therapy with contemporary protease inhibitors. Classical risk factors but not antiretroviral therapy were associated with faster CIMT progression.