Associations of epicardial fat with coronary calcification, insulin resistance, inflammation, and fibroblast growth factor-23 in stage 3-5 chronic kidney disease.
BACKGROUND
Epicardial fat, quantified in a single multi-slice computed tomography (MSCT) slice, is a reliable estimate of total epicardial fat volume (EFV). We sought to determine risk factors for EFV detected in a single-slice MSCT measurement (ssEFV) in pre-dialysis chronic kidney disease (CKD) patients. Our primary objective was to determine the association between ssEFV and coronary artery calcification (CAC).


METHODS
94 pre-dialysis stage 3-5 CKD patients underwent MSCT to measure ssEFV and CAC. ssEFV was quantified at the level of the left main coronary artery. Measures of inflammation, traditional and kidney-related cardiovascular disease risk factors were collected.


RESULTS
Mean age: 63.7 ± 14 years, 56% male, 39% had diabetes, and mean eGFR: 25.1 ± 11.9 mL/min/1.73 m2. Mean ssEFV was 5.03 ± 2.4 cm3. By univariate analysis, body mass index (BMI) (r = 0.53; P = <0.0001), abdominal obesity (r = 0.51; P < 0.0001), high density lipoprotein (HDL) cholesterol (r = - 0.39; P = <0.0001), insulin resistance (log homeostasis model assessment of insulin resistance (log HOMA-IR)) (r = 0.38, P = 0.001), log interleukin-6 (IL-6) (r = 0.34; P = 0.001), and log urinary albumin to creatinine ratio (UACR) (r = 0.30, P = 0.004) demonstrated the strongest associations with ssEFV. Log coronary artery calcification (log CAC score) (r = 0.28, P = 0.006), and log fibroblast growth factor-23 (log FGF-23) (r = 0.23, P = 0.03) were also correlated with ssEFV. By linear regression, log CAC score (beta =0.40; 95% confidence interval (CI), 0.01-0.80; P = 0.045), increasing levels of IL-6 (beta = 0.99; 95% CI, 0.38 - 1.61; P = 0.002), abdominal obesity (beta = 1.86; 95% CI, 0.94 - 2.8; P < 0.0001), lower HDL cholesterol (beta = -2.30; 95% CI, - 3.68 to -0.83; P = 0.002) and albuminuria (log UACR, beta = 0.81; 95% CI, 0.2 to 1.4; P = 0.01) were risk factors for increased ssEFV.


CONCLUSIONS
In stage 3-5 CKD, coronary calcification and IL-6 and were predictors of ssEFV. Further studies are needed to clarify the mechanism by which epicardial fat may contribute to the pathogenesis of coronary disease, particularly in the CKD population.
Department of Medicine, Queen's University, Kingston, ON, Canada.
Jasmine D
JD
Kerr
Rachel M
RM
Holden
Alexander R
AR
Morton
Robert L
RL
Nolan
Wilma M
WM
Hopman
Cynthia M
CM
Pruss
Jocelyn S
JS
Garland
D050154:Adiposity; D015415:Biomarkers / Q000032:analysis; D002114:Calcinosis / Q000097:blood / Q000175:diagnosis* / Q000453:epidemiology; D015897:Comorbidity; D003324:Coronary Artery Disease / Q000097:blood / Q000175:diagnosis* / Q000453:epidemiology; D005260:Female; D000089703:Fibroblast Growth Factor-23; D005346:Fibroblast Growth Factors / Q000097:blood*; D006801:Humans; D015850:Interleukin-6 / Q000097:blood*; D008297:Male; D024821:Metabolic Syndrome / Q000097:blood / Q000175:diagnosis* / Q000453:epidemiology; D008875:Middle Aged; D009864:Ontario / Q000453:epidemiology; D010496:Pericardium / Q000473:pathology; D015995:Prevalence; D051436:Renal Insufficiency, Chronic / Q000097:blood / Q000175:diagnosis* / Q000453:epidemiology; D012307:Risk Factors
D015415:Biomarkers; C000717427:FGF23 protein, human; D015850:Interleukin-6; D005346:Fibroblast Growth Factors; D000089703:Fibroblast Growth Factor-23