HDL cholesterol (HDL-C) has for decades been considered “good” cholesterol, conferring beneficial effects by removing other forms of cholesterol from the bloodstream. Emerging evidence, however, suggests that high circulating levels of HDL-C can be harmful.

In the cover story for the October 2022 issue of Hypertension, Gaetano Santulli, M.D., Ph.D., and colleagues published the first study examining the relationship between HDL-C and cardiovascular events in patients with hypertension. High circulating levels of HDL cholesterol were found to significantly increase the risk of cardiovascular events in hypertensive patients. The study involved more than 11,000 people with hypertension, who were followed for more than 25,000 person-years. Participants were divided into three groups: low HDL (HDL less than 40 mg/dL), medium HDL (HDL between 40 and 80 mg/dL), and high HDL (HDL greater than 80 mg/dL). Compared with the medium HDL group, the low HDL group—as expected—was at greater risk for cardiovascular events; and remarkably, the high HDL group also faced a significantly increased risk. The results suggest that algorithms now used to calculate cardiovascular risk should be revised to take high HDL cholesterol levels into consideration.

Dr. Santulli is an associate professor of medicine and of molecular pharmacology at Einstein.