After a detailed interview and physician examination, participants received both a standard cardiac CT scan using a 64-slice multidetector CT scanner and CT angiography. While the cardiac CT scan identifies calcium deposits in coronary arteries, CT angiography can also find non-calcified arterial plaques. The standard scans showed that the HIV-infected participants had levels of coronary calcium that, based on previous studies, would be expected in men who were six years older. The CT angiography revealed coronary atherosclerosis in 59 percent of the HIV-infected patients, compared with only 34 percent of controls. Five of the HIV-positive participants had critical coronary stenosis - 70 percent or greater narrowing of one or more arterial segments - something seen in none of the controls. Those participants were all referred to cardiologists for further evaluation and treatment.

"Our findings highlight the need to address reduction of cardiac risk factors early in the course of HIV disease and for caregivers to consider that even asymptomatic patients with longstanding HIV disease and minimal cardiac risk factors may have significant coronary artery disease," says Lo, who is an instructor in Medicine at Harvard Medical School. "We also found interesting associations between the degree of atherosclerosis and how long participants had been infected with HIV and with several inflammatory and immune factors. Future studies are needed to clarify the role of these nontraditional risk factors and find the best prevention and treatment strategies for these patients."