Abstract 10273: Markedly Increased Carotid Intima-Media Thickness in the Absence of Coronary Calcium Among HIV-Infected Individuals
Background: HIV-infected subjects have increased risk for atherosclerosis. Both carotid artery intima-media thickness (IMT) assessed by ultrasound and coronary artery calcium (CAC) detected by computerized tomography predict cardiovascular risk in the general population while their usefulness among subjects with HIV is less well defined. Accordingly, we evaluated and compared these two approaches in HIV-infected individuals.
Methods: We measured CAC and IMT in 253 HIV-infected and 58 uninfected adults. The distribution of IMT was compared among individuals with and without detectable CAC. The association between HIV-related factors, traditional risk factors and CAC and IMT was evaluated.
Results: The median age was 49 years for HIV-infected and 48 years for controls. The majority were men, and a similar proportion of HIV-infected individuals and controls smoked cigarettes and had hypertension. The median duration of HIV infection was 15 years, and 68% were currently being treated with antiretroviral therapy. Among the HIV patients, 37% had detectable CAC versus 28% of controls (p=0.19); 16% of the HIV-infected had CAC > 100 vs. 5% of controls (p=0.03). Among individuals with both detectable and undetectable CAC, HIV-infected individuals had a markedly higher mean IMT compared to controls even after adjustment for traditional risk factors. Among individuals with undetectable CAC, 34% of HIV patients compared to 0% of controls had a mean IMT ≥ 1mm (p<0.0001). Among HIV-infected individuals, older age, hypertension, duration of antiretroviral therapy, and lower nadir CD4 cell count were associated with higher IMT (p<0.05 for all). In contrast, only older age was associated with detectable CAC (OR 1.13, 95% CI 1.09–1.12, p<0.0001).
Conclusions: HIV-infected individuals and controls had a similar prevalence of CAC, although absolute CAC scores were slightly higher in HIV-infected individuals. In contrast, carotid IMT detected marked subclinical atherosclerosis among HIV-infected individuals, even in the absence of any CAC. While IMT was associated with both traditional and HIV-related factors, CAC was strongly associated with older age only. Thus with HIV, carotid IMT is a more sensitive indicator of subclinical atherosclerosis than CAC.
- © 2010 by American Heart Association, Inc.