HIV-positive (HIV+) individuals experience an increased burden of coronary artery disease (CAD) not adequately accounted for by traditional CAD risk factors. Coronary endothelial function (CEF), a barometer of vascular health, is depressed early in atherosclerosis and predict future events but has not been studied in HIV+ individuals. We tested whether CEF is impaired in HIV+ patients without CAD as compared with an HIV-negative (HIV-) population matched for cardiac risk factors.
In this observational study, CEF was measured noninvasively by quantifying isometric handgrip exercise-induced changes in coronary vasoreactivity with MRI in 18 participants with HIV but no CAD (HIV+CAD-, based on prior imaging), 36 age-matched and cardiac risk factor-matched healthy participants with neither HIV nor CAD (HIV-CAD-), 41 patients with no HIV but with known CAD (HIV-CAD+), and 17 patients with both HIV and CAD (HIV+CAD+).
CEF was significantly depressed in HIV+CAD- patients as compared with that of risk-factor-matched HIV-CAD- patients (P < 0.0001) and was depressed to the level of that in HIV- participants with established CAD. Mean IL-6 levels were higher in HIV+ participants (P < 0.0001) and inversely related to CEF in the HIV+ patients (P = 0.007).
Marked coronary endothelial dysfunction is present in HIV+ patients without significant CAD and is as severe as that in clinical CAD patients. Furthermore, endothelial dysfunction appears inversely related to the degree of inflammation in HIV+ patients as measured by IL-6. CEF testing in HIV+ patients may be useful for assessing cardiovascular risk and testing new CAD treatment strategies, including those targeting inflammation.