Meta-analysis of the relation of echocardiographic epicardial adipose tissue thickness and the metabolic syndrome.

Epicardial adipose tissue (EAT) is an emerging cardiometabolic risk factor, and its thickness can be measured using echocardiography. The relation of EAT to the metabolic syndrome (MS) is still unclear. A meta-analysis of published reports was performed to provide comprehensive insight on the association of EAT thickness as assessed by echocardiography and the MS. A systematic search was conducted for reports on echocardiographic EAT thickness in patients with and without the MS. Nine studies were identified. The pooled population consisted of 2,027 subjects, of whom 1,030 had the MS. EAT thickness was significantly higher in patients with the MS than in those without (standardized difference in means 1.15 mm, 95% confidence interval 0.78 to 1.53, p = 0.0001). Subgroup meta-analysis showed no difference between patients with and those without the MS by MS criteria used and echocardiographic cardiac cycle of measurement but did show a significant difference by ethnicity, with a greater difference in Caucasian subjects (standardized difference in means 1.75 mm, 95% confidence interval 1.43 to 2.07) than in other ethnic groups. In conclusion, echocardiographic EAT thickness is significantly higher in patients with the MS than in those without, but differences exist by ethnicity.