Arterial Calcification Found on Breast Cancer Screening Mammograms and Cardiovascular Mortality in Women: The DOM Project

Breast arterial calcification (BAC) has been associated with diabetes and hypertension. This prompted the authors to study the relation between BAC and cardiovascular mortality in a cohort of 12,239 women aged 50-68 years who participated in a population-based breast cancer screening project (DOM Project) in Utrecht, the Netherlands, during the period 1975-1977. Mortality data from 16-19 years of follow-up were available. The occurrence of outcome events was compared in terms of hazard ratios. Cardiovascular risk factors, including age, diabetes mellitus, hypertension, parity, Quetelet index, and smoking, were studied to identify possible confounders. Arterial calcification was seen in 9% of the women. The hazard ratio for overall mortality was 1.29 (95% confidence interval 1.06-1.58) in women with BAC detected on screening mammograms in comparison with women without BAC after correction for the above-mentioned factors. An excess of all-cause mortality was found in diabetic women with BAC (hazard ratio = 1.74, 95% confidence interval 1.19-2.56), which was also present in subgroups of coronary mortality. These results indicate that BAC is associated with an increased risk of subsequent cardiovascular death in women over age 50 years and in diabetic women in particular.