Significant amounts of atherosclerotic plaque have been found in the coronary arteries of people with HIV, even in those considered by traditional measures to be at low-to-moderate risk of future heart disease.
This is according to a study published in JAMA Network Open, which found that the higher-than-expected levels of plaque could not be attributed simply to traditional cardiovascular disease risk factors like smoking, hypertension, and lipids in the blood, but were independently related to increased arterial inflammation and immune system activation.
For this study, data from the global REPRIEVE (Randomized Trial to Prevent Vascular Events in HIV) study was used, with the Massachusetts General Hospital (MGH) playing a key coordinating role. REPRIEVE is the largest study of cardiovascular disease among people living with HIV, having enrolled 7,700 participants at more than 100 sites in 12 countries, in collaboration with the AIDS Clinical Trials Group. The newly published results are from a subset of the overall trial, consisting of 755 individuals between the ages of 40 and 75 enrolled in 31 sites across the US.
The MGH-led study found that 49% of participants had plaque in their coronary arteries. While significant narrowing of the arteries was rare, nearly a quarter had plaque which the researchers considered “vulnerable,” that is, at risk for potential future cardiovascular problems.
“The prevalence of plaque found in people with HIV was striking, though the number of lesions was limited in most people and only a portion could be explained by traditional risk factors,” said co-author Michael Lu, MD, MPH. “We learned that the plaque burden was also associated with higher levels of arterial inflammation and immune system activation independent of traditional risk scores.”
Enabling researchers to assess these nontraditional cardiovascular risk factors were two biomarkers which they hypothesized could reflect premature cardiovascular disease among people with HIV. They are interleukin 6 (IL-6), associated with immune system activation, and LpPLA2, associated with arterial inflammation.
The two biomarkers will be evaluated in the next phase of REPRIEVE for their ability to predict major events, such as heart attacks and strokes. That ongoing research will also investigate the potential of statin therapy to reduce lipid levels – its primary therapeutic target – as well as plaque and markers of inflammation.