A new UT Southwestern-led study entitled “HDL Cholesterol Efflux Capacity and Incident Cardiovascular Events” reports to have found a new biomarker – cholesterol efflux capacity – for the risk of cardiovascular disease. The study was published in the November issue of the The New England Journal of Medicine.
High-density lipoprotein (HDL) measurement is currently performed in blood tests and is an indicator of the risk to develop atherosclerosis, cardiovascular disease, and strokes. This is achieved because HDL, commonly known as “good-cholesterol,” transports fat molecules out of artery walls and deliver it to liver for excretion. However, blood tests solely measure HDL levels in the blood and not its functional capacity. This is measured by the cholesterol efflux capacity.
In this study, a team of researchers led by Dr. Anand Rohatgi, Assistant Professor of Internal Medicine at UT Southwestern, developed a method to measure cholesterol efflux capacity and determined if this new factor had a higher predictive value than the current HDL levels. They measured HDL cholesterol level, HDL particle concentration, and cholesterol efflux capacity in 2,924 adults, with no history of cardiovascular disease, previously enrolled in the Dallas Heart Study. They found that cholesterol efflux capacity had a greater predictive value then the standard HDL levels. Specifically, the authors discovered that increased cholesterol efflux capacity was associated with decreased risks for cardiovascular diseases, namely heart attacks and strokes.
Dr. Anand Rohatgi, study author commented, “So now we’re looking under the hood, so to speak, and we’re realizing that the whole story of what HDL does is not being told by HDL cholesterol levels alone. HDL is very dynamic. It has many functions that are not fully captured by the measurement of static cholesterol levels. The hypothesis has changed from an HDL-cholesterol hypothesis to an HDL-function hypothesis to better capture cardiovascular risk and provide a better target for therapy to reduce that risk. We drew on the strengths of the Dallas Heart Study to investigate thoroughly the relationship between HDL function and cardiovascular disease. What we found was a strong, graded, protective relationship between cholesterol efflux and incidence of cardiovascular events among people who were free from heart disease at baseline testing.”