Mammograms performed to check the health of the breasts could also give clues to the health of the heart, researchers say.
That's because the amount of calcium in the arteries of the breast, which can be seen on a digital mammogram, seems to reflect the amount of calcium in the coronary arteries, which supply blood to the heart.
Although women are commonly screened for breast cancer with mammography, there is no routine screening test for heart disease. Calcium in the coronary arteries is known to be an early sign of heart disease. Finding a link between calcium in the breast arteries and calcium in the coronary arteries is a reason to "pay attention," study coauthor Dr. Jagat Narula from the Icahn School of Medicine at Mount Sinai in New York City told Reuters Health by email.
Narula and colleagues will report their findings April 3 at the American College of Cardiology annual scientific session in Chicago as well as in JACC: Cardiovascular Imaging.
For the study, the Mount Sinai team analyzed heart disease risk factors, such as high cholesterol, high blood pressure, high blood sugar and smoking, in 292 women who underwent both digital mammography and a chest computed tomography (CT) scan.
They found that 42.5 percent of the women had calcium in their breast arteries, as shown by digital mammography. Those women were significantly older and had more high blood pressure and chronic kidney disease compared with women who didn't have breast arterial calcium.
Coronary artery calcium, as shown in the CT scans, was noted in 47.5 percent of the women, who were also significantly older and had more high blood pressure, chronic kidney disease and diabetes compared with the women who didn't have coronary artery calcium.
Subsequent analyses revealed that the presence of breast arterial calcium was about 70 percent accurate overall in predicting the presence of calcium in the coronary arteries. Further, it did at least as well, and in some cases better, than standard risk predictors at identifying women at high risk of heart disease.
Senior author Dr. Laura Margolies told Reuters Health by email that after digital mammography, "Women should ask their radiologists if there was any calcification in their breast arteries. This information can then be given to their primary care doctors to be used in conjunction with standard risk factors to determine if further evaluation (or treatment) would be of benefit."
She also noted that seeing images of calcification in the arteries in the breast could be "the strongest motivator for a woman to take action to reduce the chances of developing clinically significant cardiovascular disease."
Dr. Margolies pointed out that there is always the possibility of so-called false positives.
"Not all breast arterial calcification is indicative of significant cardiovascular disease. And people who are already being treated for cardiovascular disease might not derive any further benefit from knowing that the arteries in the breast are calcified, too."
Commenting by email, Dr. Joan Brem, Director of the Breast Imaging and Interventional Center at George Washington University in Washington, D.C., said, "This study demonstrates that accurate cardiovascular risk can be determined by evaluating the extent of calcification in blood vessels seen on digital mammograms, without the use of any additional radiation or risk. These exciting findings will allow women to be screened for the two most frequent life-threatening diseases at once - breast cancer and cardiovascular disease - (and allow) for determination of cardiovascular risk in a large population of women who might otherwise not get this potentially life-saving information."