• Relationship between abdominal tissue types, levels of inflammatory markers and adipokines, and CVD events [ Time Frame: Measured at completion of sample analysis ] [ Designated as safety issue: No ]
  

• How differences in age, sex, and ethnicity influence the association between ABC and CVD risk [ Time Frame: Measured at completion of sample analysis ] [ Designated as safety issue: No ]
  

Abdominal obesity is a serious condition and increases the risk for potentially life-threatening cardiovascular diseases (CVDs). Abdominal fat is made up of structurally and functionally different tissues, which include visceral fat, subcutaneous fat, and intramuscular fat. The distribution and levels of these fat tissues are highly variable among obese people, and the effects of ABC differences on cardiovascular health are not well known. Notably, the standard measure of body mass index cannot distinguish between different kinds or ratios of tissue types that make up body weight and, therefore, may not be the best measurement tool. Determining the specific measures of these tissue types by computed tomography (CT) may provide better insight into the varied CVD risk seen among different ethnicities, sexes, and ages. This study will evaluate the association between volumetric measures of ABC, CVD risk, and inflammation in terms of ethnicity-, sex-, and age-specific variables.

This substudy will use data and specimens, including blood samples and CT scans, from participants in the Multi-Ethnic Study of Atherosclerosis (MESA) for abdominal aortic calcium (AAC). Stored blood samples will be used to perform assays for several measures of inflammation and to generate new data on biomarkers and subclinical CVD measures. The existing CT scans will be used to calculate five discrete volumetric measures of ABC, which will include subcutaneous fat, visceral fat, intramuscular fat, the visceral fat to visceral cavity ratio, and the lean muscle to visceral fat ratio. There will be no study visits for this study.