Abstract MP007: Epicardial Fat Thickness: Distribution of and Associations With Cardiovascular Risk Factors in the Framingham Heart Study

Abstract

Introduction: High pericardial fat volume (fatVOL) is associated with excess cardiovascular disease (CVD), but analyses for true fat volume can be time-consuming and require specialized software. Linear epicardial fat thickness (fatTHK) can be measured quickly from cardiac magnetic resonance (MRI) images and may serve as a surrogate for fatVOL. We sought to determine the distribution and CVD risk factor correlates of high fatTHK and to compare fatTHK with fatVOL in a community-dwelling adult cohort. Methods: Participants were drawn from the Framingham Heart Study Offspring cohort (N=995, aged 65±9 years, 54% women) and underwent cardiac MRI (SSFP sequence) and multidetector CT during 2002-2005. Clinical and risk factor covariates were obtained at the preceding cycle 7 examination (1998-2001). FatVOL was determined from volumetric MDCT data. FatTHK was measured from the MRI 4-chamber view over the midlevel right ventricular free wall at end-diastole. A healthy referent subsample (N=328), free of major CVD risk factors, was used to determine sex-specific cut points for high fatTHK. Odds ratios for high (>90th percentile) fatVOL and fatTHK versus common CVD risk factors were determined. Results: FatTHK was greater in men than women and increased with age in both sexes. FatTHK correlated with fatVOL at r=0.45 (p less than 0.001) High fatTHK was >=16.0 mm in men and >=13.3 mm in women, with 20.1% prevalence in men and 18.1 % in women. In both sexes, high fatVOL was associated ( Table ) with obesity, metabolic syndrome, dysglycemia, hypertension, prevalent CVD and hypertriglyceridemia. Similar associations, with slightly lower odds ratios, were seen for fatTHK. Conclusions: Greater fatTHK is associated with an excess burden of multiple CVD risk factors. Although correlation between linear fatTHK and true fatVOL was relatively modest, both measures appear to have similar associations with common CVD risk factors. FatTHK may be advantageous in that it can be determined quickly using standard MRI sequences for ventricular function. Table. Odds Ratios for High Pericardial Fat vs. Common CVD Risk Factors fatVOL: Men fatVOL: Women fatTHK: Men fatTHK: Women Obesity, BMI >=30 kg/m2 4.34 (2.78–6.78) 3.13 (2.03–4.82) 2.52 (1.77–3.60) 2.62 (1.84–3.74) Metabolic Syndrome 3.72 (2.38–5.83) 2.60 (1.65–4.08) 2.59 (1.75–3.84) 2.21 (1.53–3.17) Dysglycemia, FPG >=100 mg/dL 2.64 (1.72–4.06) 3.05 (1.98–4.68) 1.75 (1.22–2.50) 1.56 (1.10–2.23) Hypertension, S>=140 or D>=90 mmHg 2.51 (1.66–3.78) 1.96 (1.30–2.97) 2.10 (1.48–2.98) 1.58 (1.13–2.22) Prevalent CVD 1.94 (1.17–3.21) 2.48 (1.41–4.38) 1.73 (1.17–2.55) 1.83 (1.19–2.81) Triglycerides >=150 mg/dL 1.89 (1.25–2.86) 2.21 (1.43–3.42) 1.64 (1.15–2.34) 1.98 (1.38–2.82) Low HDL: M<40, W<50 mg/dL 1.57 (1.03–2.38) 1.44 (0.91–2.28) 1.40 (0.98–1.99) 2.57 (1.80–3.67)