Breast arterial calcifications which were detected during routine annual mammography screening were considered an incidental finding as they were not associated with increased risk of breast cancer. The goal of this research was to find a correlation between the presence of BAC on mammography and cardiovascular disease and their risk factors. Thus, BAC detected during routine mammography could be valuable in identifying asymptomatic women at increased future CVD risk that may be candidates for more aggressive management.
According to Ugur Topal 2007, trying to prove the relationship between BAC and coronary artery disease those were his results: eighty (65%) of 123 patients had CAD. BAC was found in the mammography of 49 (39.8%) patients. The duration and ages of menopause of the patients with BAC were significantly higher than those without BAC (p < 0.001). And there was also significant correlation between the BAC and Gensini scores (p = 0.059). As well there was an increase in the frequency of BAC among patients with more than two vessels with stenosis (p = 0.033) [10], compared with our study, there was a significant correlation between BAC and CAD (p = 0.006), and the mean age of patients with BAC was 63.7 in comparison with the mean age for those with no BAC was 53.9 (p = 0.000).
According to Paul S. Dale 2008, which was also trying to prove the ability of BAC detected on screening mammography to discover women with increased risk of CAD and diabetes showed the following results: of 1000 consecutive women undergoing screening mammography, 181 showed a history of CAD and/or diabetes. Of those women without diabetes or heart disease, 86 of 819 (10.5%) had BAC. One hundred forty women had diabetes, of whom 57 (40.7%) had BAC, and 72 women had CAD, and of whom 36 (50%) had BAC. The association among BAC, CAD, and diabetes was extremely significant (p < .0001, 95% confidence interval [CI]). The odds ratio of having diabetes or CAD with BAC was 4.3 and 3.6 times greater than the odds of having these diseases without BAC. This large prospective study showed a significant association between BAC detected on screening mammography and if there was a personal history of CAD and diabetes, detecting that screening mammography may identify women at increased risk for these diseases [11], compared with our study, the association between BAC and CAD showed an odds ratio of 2.9 and (CI 0.96–9.218) while no association between BAC and risk factors (DM, HTN, dyslipidemia) showing the following p value 0.47.
According to Evelling L. C. Oliveira 2009, a case-control study consisting of 40 women with coronary artery disease in the case group and 40 women without any history of coronary artery disease in the control group both were matched according to age and aiming to prove that BAC detected on mammography as an independent factor indicating coronary artery disease [12].
Forty women with coronary artery disease, who were included in the case group, underwent mammography during the preceding 12 months. Cases which were proven as coronary artery disease cases either confirmed by coronary angiography or had experienced at least one episode of acute myocardial infarction [12].
Vascular calcification in breast tissue was defined as the detection of parallel linear calcified tracks along the course of a vessel that was detected on at least one mammographic viewing plane. The intensity of the calcifications, number of vessels affected and the side affected were all analyzed. The presence and intensity of the calcifications were graded as follows: Absent: No vascular calcifications; slight: Arteries that showed little calcification with distances greater than 10 mm between calcified areas, moderate: Arteries obviously outlined by calcifications over a considerable proportion of their course and severe: Arteries extensively affected, had almost continuous columns of calcification, with at least two branches were visible. All mammograms were interpreted by only one observer. The number of calcified vessels was detected independently of the intensity of calcification. The laterality of the calcification was also detected and graded as unilateral, bilateral [12].
The odds ratio (OR) for coronary artery disease was 3.56, in relation to vascular calcifications in breast tissue seen via mammography, compared with our study, it was 2.97.
In Evelling study [12], the odds ratios for the other risk factors analyzed were 4.20 for diabetes mellitus, 12.33 for arterial hypertension, and 2.53 for a family history of coronary artery disease, in agreement to our study which found no association between BAC and risk factors (DM, HTN, dyslipidemia) in both 1st and 2nd age groups showing the following p values respectively 0.56 and 0.24.
According to Evelling L.C.Oliveira 2009 [12], vascular calcifications detected in breast tissue via mammography were usually bilateral. A statistically significant difference in the intensity of the calcifications between the two groups was noticed. The median number of calcified vessels in the case group was three and none in the control group (p < 0.01).
In their analysis, the presence of vascular calcifications in breast tissue seen via mammography was an independent risk factor for coronary artery disease as they found. Some previous studies had also proven such an association. In previous studies, vascular calcifications seen via mammography were noticed in 16 to 31% of women with coronary artery disease [12].
In a study of 131 women in 2007, Ferreira et al. showed an odds ratio of 2.96 (CI 1.25–7.30) [13], compared with our study, I found an OR 2.97 (CI 0.960–9.218).
One of the interesting findings was that when the vascular calcifications in breast tissue were bilateral, the atherosclerotic process and consequent vascular calcification were almost affecting the entire arterial system [12].
According to Mohammad H. Zgheib 2010, this study showed the following results: Fifty-seven patients (mean age, 72 years 6 9.8 [standard deviation]) had BAC-positive lesions. The 115 patients (mean age, 60.4 years 6 11) without BAC were younger than those with BAC (p < .001) and BAC was significantly associated with some cardiac risk factors. Approximately 61% of patients with BAC had a family history of CHD, compared with only 44% of patients without BAC (p = .034). Presence of BAC was significantly accompanied by history of CHD (odds ratio, 2.66; 95% CI, 1.31, 5.42), CHD-equivalent disease (peripheral vascular disease, transient ischemic attack, stroke, or angina) (odds ratio, 2.25; 95% CI, 1.05, 4.79), and family history of CHD (odds ratio, 2.08; 95% CI, 1.08, 3.98). BAC showed no significant association with smoking, postmenopausal status, or hyper lipidemia and on the other hand, it had an association with hypertension (p = .051) and diabetes (p = .097).
At coronary angiography, some evidence of CHD (grades 1–4) were found in 104 patients and 68 had completely normal findings. The prevalence of BAC in patients with CHD was 36% versus 29% of patients without CHD (p = .40). We found out no correlation between BAC and any degree of CHD or distribution of stenosis. Of the 83 patients with advanced CHD (70% or greater stenosis, grade 4), only 41% patients had BAC versus 59% of patients who had not (p = .14) [14], while according to our study, the 1st group of patients (with higher age) showed that 76.5% of the BAC-positive cases of this group were cardiac patients showing a significant p value 0.022, meaning a correlation between BAC positive and being cardiac in 2nd group patients only. There was no association between BAC and risk factors in 1st and 2nd age groups with insignificant p values = 0.56 and 0.24 respectively.
According to Hekimoğlu et al. 2012, who was aiming to discuss intramammarian arterial calcifications value in the prediction of coronary artery disease, mammography was done on 55 women over 40 years of age who do coronary angiography and did not have a mammography in the past year. Coronary angiography results, intramammarian arterial calcifications, and coronary artery disease risk factors were all evaluated. The percentage of intramammarian arterial calcifications was 41.8%. A significant relationship between coronary artery disease and intramammarian arterial calcifications was proven (OR 10.8, 95% Cl 3.02–38.59). The negative predictive value and positive predictive value of intramammarian arterial calcifications for coronary artery disease were 75% and 78.3% respectively. Also advancing age was detected to be relevant with these calcifications (OR 1.15, 95% Cl 1.05–1.25). The idea that the mammography was in use as a screening tool among women over 40 and could be used also in coronary artery disease risk assessment was supported by the results in the present literature which should be confirmed by further larger group controlled studies [15], compared with our study which showed a correlation between BAC and CAD in the 2nd group only with a significant p value = 0.022 less, there was an increase in the mean age among BAC-positive cases in both age groups but it was more significant in 1st group with a p value < 0.001 while in the 2nd group, the mean age in BAC-positive cases was 68.5 and in BAC-negative cases was 67.3 giving an insignificant p value 0.605. There was no significant association between BAC and risk factors in both age groups with insignificant p values.
According to Maryam Moradi 2014, the results of this study which was done to evaluate the association between BAC and CTCA findings were as follows: the mean age of subjects without BAC (n = 115) was significantly lower than patients with BAC (n = 35) (68.03 ± 6.16 versus 54.36 ± 7.63 years, p < 0.0001). However, women with BAC showed significantly high relative frequency of different grades of coronary artery stenosis (p < 0.0001), which was the same as our study in the 2nd age group [16].
According to Maryam Moradi 2014, although they showed higher prevalence of BAC in patients with more severe coronary artery stenosis, this could be related to the effects of age as a co-variant. This could mean that both BAC and the presence of more significant coronary artery stenosis might be independently correlated with age; and as a result, older women were more susceptible to have both BAC and coronary artery stenosis. In their study, the BAC-positive patients were significantly older than the other group. Further analyses had confirmed the role of age in the correlation of BAC and CTCA findings [16].
To sum up, from the six articles compared with our study, only one showed no correlation between BAC and CAD which was the same results as the 1st age group while the rest showed a significant correlation between BAC and CAD as the results of the 2nd age group. Therefore, detection of arterial calcifications on mammography should be reported and further correlation with age should be done so that in old patients above 60 years, cardiac investigations have to be suggested.