Abdominal Body Composition, Inflammation and Cardiovascular Diseaase

描述（由申请人提供）：肥胖是一个新兴的公共健康问题，其发病率因年龄、性别和种族而异。腹部脂肪的分布也因民族而异。例如，与非西班牙裔白人相比，非洲裔美国人的内脏脂肪水平较低，而体重指数和腰围则较高。这些差异对解释腹部身体成分、炎症和心血管疾病事件之间的种族特异性关系具有重要意义。值得注意的是，身体质量指数的标准人体测量不能区分组成体重的不同类型或比例的组织类型。因此，我们建议在基线时评估1,970名年龄在45-84岁的男性和女性的腹体体积组成，这些人正在一项辅助研究中进行多种族动脉粥样硬化研究（MESA），通过计算机断层扫描（CT）检测腹主动脉钙（AAC）。MESA拥有每个参与者的生物标志物和亚临床CVD测量的广泛数据库，他们也被跟踪CVD事件。我们建议从CT扫描中测量和计算腹部身体组成的5个离散体积测量：皮下脂肪、内脏脂肪、肌肉内脂肪、内脏脂肪与内脏腔的比例和瘦肌肉与内脏脂肪的比例。我们还将对几种相关的炎症指标进行检测。利用这一数据和现有的MESA数据，我们计划验证腹部体成分测量与冠状动脉和心血管疾病事件显著相关的假设，独立于传统的CVD危险因素、炎症和亚临床CVD。我们将确定这种关联是否因年龄、性别和种族而存在差异，并将确定选定的饮食和身体活动变量的影响。此外，增强的MESA数据集的丰富性将提供机会来辨别身体成分的5种不同CT测量是否比传统的BMI和WC测量有明显的优势。这将为通过改变包括骨骼肌在内的不同部位的脂肪组成来降低心血管疾病风险的干预措施的潜在治疗靶点提供重要的生理学和临床相关信息。我们不知道有任何其他以人口为基础的研究像这样全面地研究所述目标。

DESCRIPTION (provided by applicant): Obesity is a burgeoning public health problem with the rates of this condition differing by age, sex and ethnicity. The distribution of abdominal fat also differs by ethnic group. For example, compared to non-Hispanic Whites, African Americans have lower levels of visceral fat while having higher body mass index and waist circumference. These differences have important implications for the interpretation of the ethnic-specific relationships between abdominal body composition, inflammation and incident cardiovascular disease events. Notably, the standard anthropometric measure of body mass index cannot discriminate between different kinds or ratios of tissue types comprising the body weight. Accordingly, we propose to evaluate volumetric abdominal body composition in 1,970 men and women aged 45-84 at baseline, who are being studied in an ancillary study to the Multi-Ethnic Study of Atherosclerosis (MESA) for abdominal aortic calcium (AAC) by computed tomography (CT). The MESA has an extensive database of biomarkers and subclinical CVD measures on each participant, who are also being followed for incident CVD events. We propose to measure and calculate 5 discrete volumetric measures of abdominal body composition from the CT scans: subcutaneous fat, visceral fat, intramuscular fat, the visceral fat to visceral cavity ratio and the lean muscle to visceral fat ratio. We will also perform assays for several pertinent measures of inflammation. Using this and existing MESA data, we plan to test the hypothesis that measures of abdominal body composition will be significantly associated with incident coronary and cardiovascular disease events, independent of traditional CVD risk factors, inflammation and subclinical CVD. We will determine if there are differences in this association by age, sex and ethnicity and will also ascertain the influence of selected dietary and physical activity variables. Furthermore, the richness of the augmented MESA dataset will afford the opportunity to discern whether there is clear advantage afforded by the 5 distinct CT measures of body composition over the traditional measures of BMI and WC. This will provide important physiologic and clinically relevant information on the potential therapeutic targets for interventions aimed at reducing CVD risk by altering the composition of fat in different compartments, including skeletal muscle. We are unaware of any other population-based study that is as comprehensive as this to study the stated aims.