Breast arterial calcification strong predictor of coronary artery calcification

Mammography could play a significant role in preventing heart disease in women

In a study to ascertain whether breast arterial calcification (BAC) detected with digital mammography correlates to chest CT findings of coronary artery calcification (CAC), researchers have discovered a striking relationship between the two factors. In 76% of the study cohort, women who had a BAC score of 0 also had a CAC score of 0. As the BAC score increases, there is a concomitant increase in the CAC score.

The findings indicate that the presence of BAC could play a significant role in identifying women who may benefit from coronary artery disease prevention without additional cost, time, and radiation exposure.

"The opportunity to diagnose cardiovascular risk on mammography heralds a paradigm shift in imaging," said corresponding author Laurie Margolies, Icahn School of Medicine at Mount Sinai. "Providing this knowledge to patients and ordering physicians increases the opportunity for patients to take advantage of cardiovascular risk-reduction strategies while screening for breast cancer."

The study was presented at the ARRS 2015 Annual Meeting in Toronto.

Scientific Session 13 - Breast Imaging

Abstracts 1083-4959

1226. Digital Breast Arterial Calcium Score is Predictive of Coronary Calcium Score

Margolies L*, Salvatore M, Hecht H, Yip R, Yankelevitz D, Henschke C. Icahn School of Medicine at Mount Sinai, New York, NY

Objective: The purpose of our study was to determine if breast arterial calcification on digital mammography, number of involved vessels, length of involvement, and calcification density predicts the presence of coronary artery calcium, which is known to correlate with cardiovascular disease and death. Both breast cancer and cardiovascular disease affect many women and cardiovascular disease is the leading cause of death of American women, yet breast cancer is the more feared disease. The age range of those screened for breast cancer is the same as those who would most benefit from preventive cardiology. Therefore, an opportunity for concurrent cardiovascular disease risk assessment may exist without additional cost, patient time, or radiation. If breast arterial calcification (BAC) is a surrogate for coronary calcium score or if it could augment documented risk factors, mammography could play a role in coronary artery disease prevention.

Materials and Methods: Our study, which was HIPAA-compliant and approved by our institutional review board, consisted of 371 women who had a digital mammogram and unenhanced CT scan performed within 1 year of each other. Calcified vessels were identified on the mammogram, and, if present, were evaluated as to the number of vessels involved and the length of involvement: less than 1/3, between 1/3 and 2/3, and greater than 2/3. Density of involvement was characterized as mild (one vessel wall, no increase in density of the vessel, or both), moderate (increased density of the vessel manifested as clouding), or severe (the lumen obscured by calcium). The ordinal score for coronary artery calcification (CAC), previously established, was obtained from the CT scan. Logistic regression analysis was used.

Results: When the ordinal CAC score was 0, the ordinal BAC score was 0 in 143 (76%) of 187 women. When the ordinal CAC score was 4-12, then the ordinal BAC score is 4-12 in 42 (55%) of 77 women. The presence of any BAC confers a statistically significant risk of CAC. BAC has a 2.8 odds ratio of CAC = 4. The length of BAC correlates with increased risk of CAC (p < 0.0001), as did the number of vessels involved (p < 0.0001). The density of involvement, however, was the most significant predictor of coronary calcification; if there is severe BAC density, 23/26 had CAC with 18/26 (69%) having CAC = 4.

Conclusion: The presence of BAC is a strong predictor of the presence of CAC. Our study is the first to our knowledge to correlate calcification on digital mammography with the extent of coronary artery calcifications on chest CT. It documents that finding breast arterial calcifications on mammography significantly increases the likelihood of CACs and that as the ordinal BAC score increases, there is a concomitant increase in the ordinal CAC score. These results argue for the inclusion of BAC in mammography reports and education of primary care physicians about this important additional risk predictor for coronary artery disease so that primary cardiovascular disease prevention strategies can be implemented as clinically warranted.