Inhibiting activity of a transfer protein to raise high-density lipoprotein (HDL) cholesterol levels is not as effective a heart disease therapy as it is believed to be, according to a new study.
Scientists at the Jean Mayer USDA Human Nutrition Research Center on Aging (USDA HNRCA) at Tufts University and Boston University School of Medicine found a link between low plasma cholesterol ester transfer protein (CETP) activity and increased risk of heart disease in the Framingham Heart Study population.
CETP is a protein that shuttles cholesterol throughout the body, thus controlling the levels of HDL, low-density lipoprotein (LDL), and very-low-density lipoprotein (VLDL) in the blood.
"Our findings differ from studies suggesting that inhibiting CETP activity would bring a cardiovascular benefit by raising HDL, the so-called good cholesterol credited with lowering the risk of heart disease. In a clinical trial testing that hypothesis, heart disease unexpectedly advanced in a surprising number of participants," said senior author Dr Jose Ordovas.
Based on those results, the researchers examined CETP activity in 1,978 Caucasian men and women with a mean age of 51 years and no history of heart disease.
They analysed 15 to 18 years of study visits looking for first cardiac events including heart failure, heart attack, angina, stroke and peripheral vascular disease.
"By the end of the follow-up period, 320 men and women had experienced their first cardiac event. Participants with low CETP activity were 18% more likely to develop cardiovascular disease than people with CETP activity above the median," said Ordovas.
A more in-depth investigation of models eliminated the possibility that age, sex and common risk factors such as smoking, weight, diabetes, and cholesterol levels interfered with the findings.
The results are published in the latest issue of Circulation.