Carotid intima-media thickness among human immunodeficiency virus-infected patients without coronary calcium

Subjects infected with human immunodeficiency virus (HIV) have increased risk for atherosclerosis. Carotid artery intima-media thickness (IMT) assessed using ultrasound and coronary artery calcium (CAC) detected using computed tomography predict cardiovascular risk in the general population; however, their usefulness and comparability in patients with HIV are less well defined. The purpose of this study was to compare IMT and CAC in the detection of atherosclerosis in subjects with HIV. CAC and IMT were measured in 253 HIV-infected and 58 uninfected adults. Associations among HIV-related factors, traditional risk factors, and CAC and IMT were evaluated. The distribution of IMT among subjects with and without CAC was compared. Among the patients with HIV, 37% had detectable CAC compared to 28% of controls (p = 0.19); 16% of the patients with HIV had CAC >100 compared to 5% of controls (p = 0.03). With either detectable or undetectable CAC, HIV-infected subjects had higher IMT compared to controls (1.02 ± 0.34 vs 0.78 ± 0.12 mm, p <0.0001), even after adjustment for traditional risk factors. Among those with undetectable CAC, 34% of patients with HIV had markedly increased IMT (<1 mm) compared to no controls (p <0.0001). HIV-related factors were associated with IMT but not with CAC. In conclusion, patients with HIV and controls had similar rates of detectable CAC, while absolute CAC scores were modestly higher in the HIV group. Conversely, carotid IMT detected advanced subclinical atherosclerosis in patients with HIV even in the absence of CAC. Thus, with HIV, IMT is associated with disease-related factors and may be a more sensitive indicator of subclinical atherosclerosis than CAC.