Inflammation appears to be the reason patients living with HIV have higher heart disease risk.
HIV's evolution from a certain death sentence to a treatable chronic condition doesn’t mean those who have the disease escape all risk.
It turns out that patients with HIV have nearly twice the risk of a heart attack, and the proportion of deaths attributable to heart disease has tripled in the past 15 years. The risks persist even when the virus can no longer be detected in the blood, due to treatment from antiretroviral drugs, according to a new study from Northwestern University.
"The actual risk of heart attack for people with HIV was roughly 50% higher than predicted by the risk calculator many physicians use for the general population,” said lead author Matthew Feinstein, MD, in a statement. The study was published in JAMA Cardiology.
Risk calculators help physicians predict which patients are likely to have a heart attack or stroke, so that those patients can be prescribed medications like statins to reduce their risk of an event.
The study involved 20,000 patients with HIV who were receiving care at 1 of 5 large participating sites around the country. (Overall, about 1.2 million people in the United States have HIV.) The researchers compared heart attack rates in this group with those predicted in the general population.
What drives the added risk? The HIV infection itself, not the treatment, apparently. Chronic inflammation, which is also caused by diabetes and by smoking, is a known risk factor for heart disease. The infection still causes inflammation even in those whose blood test shows no detectable levels of the virus. This causes plaque buildup in patients at a faster rate than the general population. Before antiretroviral drugs allowed patients to live for decades with HIV, this effect was less apparent.
“It’s the inflammatory state that seems to drive this accelerated aging and these higher risks for heart disease, which are becoming more common in HIV patients as they live longer,” Feinstein said.
Risk calculators based on scores from the general population can be useful with the HIV population, the researchers found.
"Regardless of age, sex or race, the risks are higher in people with HIV," Feinstein said. Among those with HIV, the study found the existing predictor tool was least accurate in African American men and women and most effective for Caucasian men. Northwestern has a clinical trial underway to study how well common heart medications like statins perform in preventing heart attacks and strokes among those with HIV.