Preclinical atherosclerosis due to HIV infection: carotid intima-medial thickness measurements from the FRAM study

Abstract
Background: Cardiovascular disease (CVD) is an increasing cause of morbidity and mortality in HIV-infected patients. However, it is controversial whether HIV infection contributes to accelerated atherosclerosis independent of traditional CVD risk factors. Methods: Cross-sectional study of HIV-infected participants and controls without pre-existing CVD from the study of Fat Redistribution and Metabolic Change in HIV Infection (FRAM) and the Multi-Ethnic Study of Atherosclerosis (MESA). Preclinical atherosclerosis was assessed by carotid intima-medial thickness (cIMT) measurements in the internal/bulb and common regions in HIV-infected participants and controls after adjusting for traditional CVD risk factors. Results: For internal carotid, mean IMT was 1.17 ± 0.50 mm for HIV-infected participants and 1.06 ± 0.58 mm for controls (P < 0.0001). After multivariable adjustment for demographic characteristics, the mean difference of HIV-infected participants vs. controls was 0.188 mm [95% confidence interval (CI) 0.113–0.263, P < 0.0001]. Further adjustment for traditional CVD risk factors modestly attenuated the HIV association (0.148 mm, 95% CI 0.072–0.224, P = 0.0001). For the common carotid, HIV infection was independently associated with greater IMT (0.033 mm, 95% CI 0.010–0.056, P = 0.005). The association of HIV infection with IMT was similar to that of smoking, which was also associated with greater IMT (internal 0.173 mm, common 0.020 mm). Conclusion: Even after adjustment for traditional CVD risk factors, HIV infection was accompanied by more extensive atherosclerosis measured by IMT. The stronger association of HIV infection with IMT in the internal/bulb region compared with the common carotid may explain previous discrepancies in the literature. The association of HIV infection with IMT was similar to that of traditional CVD risk factors, such as smoking.