Breast calcification on mammogram ‘especially predictive’ of CVD risk in younger women

Key takeaways:

• Breast arterial calcification seen on routine mammograms may predict CVD risk.
• Women with higher calcification levels are at greater risk.

Breast arterial calcification seen on routine mammograms, especially among younger women, is associated with increased risk for death and adverse cardiovascular outcomes, including heart failure, myocardial infarction and stroke, data show.

“There is a lot of information residing within women's mammograms that is currently sitting around, unused,” Lori B. Daniels, MD, MAS, cardiologist and medical director of the cardiovascular intensive care unit at UC San Diego Health, told Healio. “Since most women over age 40 years get annual mammograms, this is information that is available with no additional cost or radiation. Many women with breast arterial calcification (BAC), and in particular younger women, may not know they are at increased risk for CVD. BAC may help alert women and their doctors to an increased cardiovascular risk, which then could trigger improved heart-healthy lifestyle modifications and a closer look at and attention to heart health. If women learn that they are at increased risk, there is plenty of time — especially for younger women — to make lifestyle and other changes to lower that risk.”

For the single-center, retrospective study, researchers analyzed data from 18,092 women with a mean age of 57 years who received a mammogram between 2007 and 2016 at UC San Diego Health. Researchers quantified BAC using an AI-generated score (cmAngio, CureMetrix) and evaluated associations between BAC and mortality and a composite of acute myocardial infarction, heart failure, stroke and mortality, adjusted for age, race, and CV risk factors including type 2 diabetes, smoking, blood pressure, cholesterol and history of CVD and chronic kidney disease.

The findings were published in JACC: Advances.

Within the cohort, 13% had diabetes, 36% had hypertension, 40% had hyperlipidemia and 5% reported smoking.

During a median follow-up of 4.8 years, 7.8% of women with BAC seen on mammograms and 2.3% of women without BAC died (P < .001). During median follow-up of 4.3 years, adverse CV events occurred in 12.4% and 4.3% of women with and without BAC, respectively (P < .001).

Compared with women with no BAC seen on mammograms, those with BAC had adjusted HRs of 1.49 for mortality (95% CI, 1.33-1.67; P < .001) and 1.56 for the composite outcome (95% CI, 1.41-1.72; P < .001). Results persisted after excluding women prescribed statin therapy and those with baseline atherosclerotic CVD.

Each 10-point increase in the BAC score was independently associated with higher risk for mortality (HR = 1.08; 95% CI, 1.06-1.11; P < .001) and the composite outcome (HR = 1.08; 95% CI, 1.06-1.1; P < .001).

In analyses stratified by age groups, women in the youngest age group of age 40 to 59 years had the highest residual risk associated with BAC on mammogram, with an adjusted HR of 1.51 for mortality (95% CI, 1.22-1.87) and an adjusted HR of 1.52 for the composite outcome (95% CI, 1.25-1.85).

“The higher the calcium, the higher the risk,” Daniels told Healio. “This was true even after accounting for traditional cardiovascular risk factors. BAC was especially predictive of future risk in younger women, which is important because these are women who might not be thinking about heart disease; they might not know they are at risk.”

Daniels said more study is needed on developing evidence-based pathways for the best ways to report BAC and respond to BAC once it is discovered on a mammogram.

“We need to figure out how to incorporate BAC into a woman’s overall cardiovascular risk profile and how to use the added information to make a more personalized and more accurate risk assessment, in accordance with other risk factors that are already established,” Daniels told Healio. “Another important step is to raise awareness within the medical community about BAC. There is a lot of studying that needs to be done, but starting to report BAC might be an important next step.”

For more information:

Lori B. Daniels, MD, MAS, can be reached at lbdaniels@ucsd.edu.