Women’s bodies are different from men’s in ways that medicine is still learning. Meanwhile, their risk of serious cardiovascular events can be underestimated if their distinct risk profiles are blurred with men’s.

The latest example of important sex differences centers on the plaque burden in coronary arteries — a measure of fat and cholesterol deposits that also accounts for blood vessel size.

Women tend to have lower volumes of plaque than men, but their total plaque burden is higher because the fatty deposits take up a larger fraction of their smaller coronary arteries. Their risk for a heart attack or hospitalization for chest pain emerged when their plaque burden was lower than men’s, and their risk climbed more steeply, too, a new study published Monday in Circulation: Cardiovascular Imaging concluded.

“What stood out was that although women had lower overall plaque volumes, their risk appeared to emerge at lower plaque burden levels,” lead author Jan Brendel, a postdoctoral research fellow at the Cardiovascular Imaging Research Center at Massachusetts General Hospital and Harvard Medical School, told STAT via email. “At the same time, we also observed substantial overlap between women and men, especially at higher plaque levels. So rather than a dramatic difference, the results suggest nuanced variation in how coronary plaque relates to risk.”