Farmington, CT - A new study has shown that breast arterial calcifications (BACs) seen on mammograms could one day be used to indicate a woman's risk of coronary artery disease [1]. Dr Michelle A Rotter (University of Connecticut School of Medicine, Farmington) and colleagues report their findings in the March/April 2008 issue of Menopause.

They discovered a significant association between BACs and most of the major CAD risk factors in their study in almost 2000 women, and they also found a higher occurrence of cardiovascular morbidity among women who were BAC positive. However, second author Dr Peter Schnatz (Hartford Hospital, CT) told heartwire that, at the moment, the discovery of BACs on mammogram "is not enough to warrant a workup. It may be a flag to think about CAD if it hasn't been considered and to encourage people to have appropriate testing of blood pressure, cholesterol, and to rule out diabetes, etc."

But the study is ongoing, the researchers explain, so they hope to be able to provide additional longitudinal data that will help evaluate the role of BACs as a predictor of CAD. "The goal of the follow-up study is to determine the percentage of women with BACs without CAD during the initial survey who later develop CAD and/or atherosclerotic cardiovascular disease."

Rotter et al explain that breast arterial calcifications are common but often unreported findings on screening mammograms, with previous studies reporting the prevalence of BACs on mammograms to be up to 17.5%. The largest study to date on this subject, reported in 2004, was based on a cohort of almost 13 000 women but found BACs to be present in just 3% of women, they note. However, this was based on mammograms obtained approximately 30 years earlier, and contemporary mammograms employ much more advanced high-resolution radiography, they note.

They studied 1919 women presenting for breast cancer screening mammography who completed questionnaires and gave their consent for their mammograms to be analyzed independently for the presence of BACs by certified radiologists. The latter were blinded to the results of the questionnaire, which assessed major risk factors for CAD.

Of the 1919 women, 268 were BAC positive, giving a BAC prevalence of 14%. Five cardiovascular risk factors—age, hypertension, hypercholesterolemia, diabetes mellitus (DM), and menopause—were significantly more prevalent in the BAC-positive population (p<0.001). The BAC-positive group also had a significantly higher (p<0.001) occurrence of atherosclerotic cardiovascular disease events—angina, previous MI, previous abnormal angiography, previous stroke, and previous coronary artery bypass graft.

BACs were strongly associated with atherosclerotic cardiovascular disease events (odds ratio 2.29 as compared with other CAD risk factors, including hypertension, smoking, DM, age, and family history of atherosclerotic cardiovascular disease).

Rotter et al say some have suggested that this is an age-related phenomenon, as the presence of BACs clearly increases with age. To address this, they compared the incidence of BACs, by age groups, of those with and without atherosclerotic cardiovascular disease.

In this analysis, in all three age groups (younger than 55 years, 55-64 years, and 65 years and older), the prevalence of BACs was statistically higher in atherosclerotic CVD-positive women. In addition, there was no significant effect by age—as a continuous variable—on the prevalence of BACs with atherosclerotic cardiovascular disease or CAD risk factors, they note.

"These data collectively suggest that BACs may not merely be an age-related phenomenon. Given the significant difference even in younger women, BACs may have utility as a cardiovascular disease risk indicator, including in younger women who may yet not have manifested CAD," the researchers say.

They reiterate, however, that "it has yet to be determined whether screening for BACs is an effective tool in screening for CAD," stressing that their follow-up study may help shed more light on this issue.