How to interpret epicardial adipose tissue as a cause of coronary artery disease: a meta-analysis

Background Experimental and clinical studies have suggested that epicardial adipose tissue (EAT) may cause coronary artery disease (CAD). A meta-analysis was conducted to investigate the relationship between EAT and CAD. Methods A systematic literature search of Cochrane, Medline, Pubmed, Elsevier, Springerlink, Ovid, and Embase from their respective inceptions to August 2011 was conducted using specific search terms such as 'epicardial adipose tissue' and 'epicardial fat'. Data were extracted from applicable articles and mean differences or risk ratio, including 95% confidence intervals (CI), were calculated using RevMan 5.1 software. Results A total of 15 case-control studies and one case-sectional study (N = 2872 patients) were identified. Compared with the non-CAD group, EAT thickness and volume were significantly higher in the CAD group (mean difference 1.57 mm, 95% CI: 0.74, 2.40, P < 0.00001; mean difference 15.22 ml, 95% CI: 7.58, 22.87, P < 0.0001). Patients in the higher EAT tertile (>= 100 ml) were more likely to have CAD compared with those in the lower EAT tertile (< 100 ml) (risk ratio 0.69, 95% CI: 0.52, 0.92, P = 0.01). Patients with coronary plaque also had increased EAT volume compared with patients without coronary plaque (mean difference 24.90 ml, 95% CI: 9.99, 39.81 P = 0.001). EAT volume was not different in patients whose coronary artery calcium scores were less than or equal to 10 or greater than 10 (mean difference -17.28 ml, 95% CI: -52.01, 17.44, P = 0.33). Conclusion On the basis of the current evidence, EAT seems to be an effective marker in the prediction of CAD. Coron Artery Dis 23: 227-233 (C) 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins. Coronary Artery Disease 2012, 23: 227-233