Study Finds Even Low Plaque Levels Raise Heart Attack Risk in Women

Women may face a higher risk of heart attack even at lower levels of artery plaque compared to men, according to a new study led by researchers from Harvard Medical School. The findings, published in Circulation: Cardiovascular Imaging, suggest that current definitions of high cardiovascular risk may underestimate danger in women.

It is well known that women typically have less artery-clogging plaque than men. However, the researchers wanted to understand how differences in plaque volume affect the likelihood of major adverse cardiovascular events, such as a heart attack or stroke. The study analyzed data from 4,267 outpatients with chest pain and no prior history of coronary artery disease, including 2,199 women.

Using advanced imaging, the team measured total plaque volume and plaque burden—the proportion of plaque relative to the size of the coronary artery. They found that plaque was less common in women than in men (55% versus 75%), and women had lower total plaque volume. Despite this, women experienced similar rates of major adverse cardiovascular events compared to men (2.3% versus 3.4%).

Importantly, the risk threshold differed by sex. In women, cardiovascular risk became elevated at a total plaque burden of 20%, compared to 28% in men. Moreover, risk increased more sharply in women at lower plaque levels, whereas in men it rose more gradually and required greater plaque accumulation.

Researchers suggest that because women generally have smaller coronary arteries, even modest plaque buildup may have a greater impact. The findings highlight the need for sex-specific interpretation of coronary imaging and more tailored strategies to assess and manage heart disease risk in women.

REFERENCE: Brendel, Jan M., Mayrhofer, Thomas, et al.; Risk in Women Emerges at Lower Coronary Plaque Burden Than in Men: PROMISE Trial; Circulation: Cardiovascular Imaging; doi: 10.1161/CIRCIMAGING.125.019011; https://doi.org/10.1161/CIRCIMAGING.125.019011