A new study led by Samar R. El Khoudary, PhD, MPH, and colleagues at the University of Pittsburgh Graduate School of Public Health examined 1,138 women over the age of 45 years who were initially included in the Multi-Ethnic Study of Atherosclerosis cohort, which included a large, diverse population. Women who experienced unknown or early menopause, defined as an onset not surgically induced, at age 45 years or younger, were excluded.

Dr. El Khoudary’s team determined that, after adjusting for potential confounding effects, the total number and size of the high-density lipoprotein particles (HDL-P), not the cholesterol-carrying capacity of the HDL-C, is what matters. The researchers identified carotid intima-media thickness (cIMT) and carotid plaque accumulation as targets to evaluate potential associations with different HDL factors. It was determined that the higher the overall HDL-P, the lower the cIMT (P = .001), and that larger HDL-P was associated with an increased cIMT close to menopause but a decreased cIMT with advancing age.

Higher HDL-C, on the other hand, was associated with higher plaque accumulation (P = .04), representing the greatest proatherogenic risk for women aged greater than 10 years postmenopause with a later age of onset. Proatherogenic risk increases the risk of hospitalization, associated morbidity, and mortality due to the complications of established coronary artery disease.

In a recent interview with NBC News, Dr. El Khoudary described the key takeaways of the study. “The most important message here is that measuring the total cholesterol might not be enough in postmenopausal women, and high total HDL cholesterol in postmenopausal women could mask a significant heart disease risk that we still need to understand,” said El Khoudary. “When a woman was close to menopause, the larger particles were associated with a greater risk of atherosclerosis,” she added.

Women who had more of the smaller HDL particles had a lower risk of developing early signs of heart disease, as measured by a thickening of the artery walls. “Our findings imply the measure of total cholesterol may not be enough. We need to look more carefully at these particles,” she said.

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