Multiethnic Study of Breast Arterial Calcium Gradation and CVD

描述（由申请方提供）：目前，乳腺X线摄影检测到的乳腺动脉钙化（BAC）被认为是一种无临床意义的偶然发现，因为它们与乳腺癌风险增加无关。然而，乳腺X线检查中BAC的存在与几种（但不是全部）传统心血管疾病（CVD）风险因素以及流行和偶发CVD相关。因此，在常规乳房X线摄影中检测到的BAC是一个值得注意的发现，在识别未来CVD风险增加的无症状女性方面可能是有价值的，这些女性可能是更积极管理的候选人。此外，在女性亚临床动脉粥样硬化负担的测量中存在显著差异（即，冠状动脉钙化），BAC也是如此，尽管数据非常有限。先前关于BAC的研究的另一个值得注意的局限性是依赖于BAC的存在与不存在;迄今为止还没有研究确定BAC的分级。这三个具体目标是：1）建立一个年龄在60至79岁之间的多种族队列（n= 5，400），其中白色女性（n= 1，350; 25%）、非裔美国人（n= 1，350; 25%）、亚裔（n= 1，350; 25%）和西班牙裔/拉丁裔（n= 1，350; 25%）女性的代表性相等。所有受试者将在北方加州的三个Kaiser Permanente医疗中心进行常规筛查乳房X线摄影时招募（超过2年），并且在基线时将无临床CVD。将使用一种新的经验证的密度测定法来估计BAC质量（以毫克为单位）使用数字乳房X线照片; 2）记录BAC质量的种族/民族差异，并检查BAC质量与社会人口学背景、CVD家族史、传统和新的CVD危险因素、生殖健康因素、心理社会因素、选定的矿物质代谢因素的关联，选定药物使用（他汀类药物和含氮双膦酸盐）、乳房大小和睡眠相关因素;探讨BAC质量对冠心病、脑血管病、心力衰竭、外周血管疾病与总CVD的关系，并确定是否将BAC质量添加到基于传统危险因素的预测模型中，以改善总CVD及其组分的风险分类。实现这些目标将为BAC质量作为评估CVD风险的筛查工具的实用性提供新的见解。 公共卫生相关性：乳腺X线摄影是一种常见的，廉价的和广泛接受的筛查测试，建议所有妇女从40岁开始;乳腺X线摄影中乳腺动脉钙化（BAC）的检测和量化有可能成为心血管风险增加的有用标志物。如果在常规乳房X光检查中观察到动脉钙（特别是大量），则可能表明存在许多心血管疾病风险因素，并且可能增加未来心血管疾病事件的风险，因此可能是识别低或中度风险女性的有用筛查工具。可能受益于更积极的治疗干预。

DESCRIPTION (provided by applicant): Currently, mammographically-detected breast arterial calcifications (BAC) are considered an incidental finding without clinical importance since they are not associated with increased risk of breast cancer. However, presence of BAC on mammography correlates with several (but not all) traditional cardiovascular disease (CVD) risk factors and with prevalent and incident CVD. Thus, BAC detected during routine mammography is a noteworthy finding that could be valuable in identifying asymptomatic women at increased future CVD risk that may be candidates for more aggressive management. In addition, there are notable differences in measures of subclinical atherosclerosis burden in women (i.e., coronary artery calcification) by race/ethnic background, and the same appears to be true for BAC, although data are very limited. Another noteworthy limitation of prior research on BAC is the reliance on absence vs. presence of BAC; no study to date has determined gradation of BAC. The 3 specific aims are: 1) To establish a multi- ethnic cohort (n=5,400) between the ages of 60 and 79 years with equal representation of white (n=1,350; 25%), African-American (n=1,350; 25%), Asian (n=1,350; 25%) and Hispanic/Latina (n=1,350; 25%) women. All participants will be recruited at the time of their regular screening mammography (over a 2 year period) at three Kaiser Permanente of Northern California medical centers and will be free of clinical CVD at baseline. A new, validated densitometry method will be used to estimate BAC mass (in milligrams) using digital mammograms; 2) To document race/ethnic variation in BAC mass and to examine associations of BAC mass with sociodemographic background, family history of CVD, traditional and novel CVD risk factors, reproductive health factors, psychosocial factors, selected mineral metabolism factors, selected medication use (statins and nitrogen-containing bisphosphonates), breast size and sleep-related factors; and 3) To elucidate the role of BAC mass in the prediction of coronary heart disease (CHD), cerebrovascular disease, heart failure, peripheral vascular disease and total CVD and to determine whether adding BAC mass to predictionmodels based on traditional risk factors improves classification of risk for total CVD and its components. Accomplishing these aims will provide novel insights into the utility of BAC mass as a screening tool to assess CVD risk. PUBLIC HEALTH RELEVANCE: Mammography is a common, inexpensive and widely accepted screening test that is recommended to all women starting at age 40; the detection and quantification of breast arterial calcification (BAC) in mammograms has the potential to be a useful marker of increased cardiovascular risk. If arterial calcium is noted (and particularly large amounts) in a routine mammogram, it may suggest the existence of a number of CVD risk factors and possibly an increased risk of future CVD events and thus may be a useful screening tool for identifying women at low or moderate risk who may benefit from more aggressive therapeutic intervention.