Paracardial fat sits in pockets around the heart. These pockets lie between the heart and another type of fat that covers the heart called epicardial fat, the study authors explained.
Epicardial fat provides energy to the heart, but paracardial fat has no known beneficial function, the researchers said.
“We are showing for the first time that paracardial fat is associated with greater risk of calcification [calcium build-up] in postmenopausal women, more than in premenopausal women,” said lead researcher Samar El Khoudary. She’s an assistant professor of epidemiology at the University of Pittsburgh Graduate School of Public Health.
“Premenopausal women also have this type of fat, but it increases significantly as estrogen levels drop during menopause,” she explained.
El Khoudary’s team found that a 60 percent increase in paracardial fat was associated with a 160 percent greater risk of calcium build-up in the heart’s blood vessels in postmenopausal women versus pre- or early menopausal women.
Postmenopausal women are at risk for even more calcification in their coronary artery as their levels of paracardial fat rise, El Khoudary said.
However, while the study found an association between increased paracardial fat and greater calcium build-up in postmenopausal women, it could not prove a cause-and-effect relationship.
For the study, El Khoudary and her colleagues collected data, including CT heart scans and blood samples, on 478 U.S. women who took part in the Study of Women’s Health Across the Nation.
The women were in varying stages of menopause. Their average age was 51. None of the women was on hormone replacement therapy.
In an earlier study, El Khoudary’s team found that an increase in paracardial fat after menopause results from a drop in the hormone estradiol, a form of estrogen. Increased levels of epicardial fat were linked to other risk factors, such as obesity, El Khoudary said.