Epidemiology of Breast Arterial Calcification

描述（由申请人提供）：研究假设是乳房X线照片上看到的乳腺动脉钙化（BAC）可以识别冠状动脉疾病（CAD）风险增加的女性。现在，将近70%的40岁以上的妇女每年例行进行乳房X光检查。每年进行的近4000万次检查可用于评估BAC，而无需任何额外费用或改变当前的乳房X线摄影技术。在无症状女性中，识别出BAC有可能大幅降低心脏病发作和CAD猝死的发生率。在BAC可用于临床之前，需要使用最先进的乳房X线摄影技术来充分确定年龄特异性BAC患病率。然后需要将BAC与熟知的CAD风险因素和冠状动脉粥样硬化指标进行比较。虽然这可以在前瞻性研究中完成，但我们可以使用冠状动脉钙化流行病学（ECAC）研究中已经获得的数据来实现相同的目标。使用这个预先存在的数据库满足这个NHLBI R21赠款的要求之一。冠状动脉钙化（CAC）是在电子束计算机断层扫描（EBCT）检查中无创检测的。CAC量与动脉粥样硬化斑块面积有良好的相关性。这项基于人群的研究有助于建立CAC的存在和数量分布以及CAC的预测因子。该数据库包括CAD风险因素的临床和实验室评估、EBCT结果和体格检查结果。最终将包括不良临床事件的信息。在该研究的12年历史中，有612名女性参与者接受了一次或多次乳房X光检查。许多妇女做了10次或更多的乳房X光检查。该提案是评估所有这些乳腺X光检查的BAC，并将结果与数据库中已有的信息进行比较。新获得的乳房X线照片数据与现有数据相结合，使这成为一项非常全面的研究，并且仍然可以在两年的时间内完成，并且具有R21赠款的资金限制。研究结果可用于帮助设计未来的研究，以前瞻性地评估在乳腺X线摄影检查中具有适当BAC特征的无症状女性中制定CAD预防和早期治疗措施的影响。

DESCRIPTION (provided by applicant): The study hypothesis is that breast arterial calcification (BAC) seen on mammograms can identify women with an increased risk of coronary artery disease (CAD). Annual mammograms are now routinely obtained on nearly 70% of women over forty years of age. The nearly 40 million examinations performed every year could be used to evaluate for BAC without any additional cost or change in current mammographic techniques. Identification of women with BAC has potential to substantially decrease the rate of heart attack and sudden death due to CAD in asymptomatic women. Before BAC can be used in a clinical setting, the age-specific prevalence of BAC needs to be fully defined using state of the art mammographic techniques. BAC then needs to be compared with well understood CAD risk factors and measures of coronary atherosclerosis. While this could be accomplished in a prospective study, we can attain the same goals using data already acquired in the Epidemiology of Coronary Calcification (ECAC) Study. Using this preexisting database fulfills one of the requirements for this NHLBI R21 Grant. Coronary artery calcification (CAC) is detected non-invasively on electron beam computed tomographic (EBCT) exams. CAC quantity correlates well with atherosclerotic plaque area. This population-based study has been instrumental in establishing the distribution of presence and quantity of CAC as well as the predictors of CAC. The database includes clinical and laboratory assessments of CAD risk factors, results of EBCTs, and findings on physical examinations. It will ultimately include information on adverse clinical events. There are 612 female participants who had one or more mammograms during the 12-year history of that study. Many women had 10 or more mammograms. The proposal is to evaluate all of these mammograms for BAC and compare the findings with information already in the database. The combination of newly acquired data from mammograms with the existing data allows this to be a very comprehensive study and still be completed in the two-year time period and with the funding constraints of this R21 grant. The findings can then be used to help design a future study to prospectively evaluate the impact of instituting preventive and early therapeutic measures for CAD in asymptomatic women with the appropriate features of BAC on mammography.