Quantity and quality of cardiovascular fat in women at midlife: associations with various markers of cardiovascular disease risk

Background: Cardiovascular fat (CF) is a complex metabolically active organ and a cardiovascular disease (CVD) risk factor. Postmenopausal women have more CF compared to premenopausal women that may partly contribute to their increased risk of CVD. \ud Objectives: Our objectives were to determine whether CF quantities differed by race; whether CF quantities were associated with adipokines and coronary artery calcification (CAC) progression; and whether the quality of CF depots, measured via radiodensity, were associated with CVD risk measures in women at midlife.\ud Methods: We evaluated participants from the SWAN Cardiovascular Fat Ancillary Study (n=562 midlife women; mean age 50.9 ± 2.9 years; 62% White; 38% Black) who had cross-sectional measures (volumes and/or radiodensity) of CF depots (epicardial fat (EAT), paracardial fat (PAT), total heart fat (TAT), and aortic perivascular fat (PVAT)). Sample sizes varied for each study aim based on applied exclusion criteria (range 524 to 222). Multivariable linear or logistic regression models were used for analyses. \ud Results: Whites had higher quantities of CF for all depots compared to Blacks, independent of cardiovascular risk factors and abdominal visceral fat (VAT). Race modified the associations between adiposity measures and CF quantities such that Whites had more PAT for higher levels of BMI than Blacks; whereas, Blacks had more EAT for higher levels of VAT than Whites. PAT was positively associated with leptin independent of cardiovascular risk factors and VAT, with stronger associations among Whites compared with Blacks. Lastly, we found that lower TAT radiodensity (poorer quality) was associated with a less favorable cardiometabolic profile and women with mid-range radiodensity values had significantly lower odds of CAC presence compared to low radiodensity values, independent of cardiovascular risk factors and BMI. \ud Conclusions: These analyses contribute to public health significance by enhancing our understanding of potential contributions of the quantity and quality of separate CF depots to CVD risk in midlife women. We found that the quantity of the mostly overlooked PAT depot may be especially important among midlife women with independent associations with leptin. Future studies should evaluate CF depots separately and further explore CF radiodensity as a marker of fat quality