Circulating vaspin levels and epicardial adipose tissue thickness are associated with impaired coronary flow reserve in patients with nonalcoholic fatty liver disease

Background: Patients with nonalcoholic fatty liver disease (NAFLD) have a reduced coronary flow reserve (CFR) and an increased risk of cardiovascular disease. The fat cells that surround coronary arteries may play a central and underrecognized role in development of cardiovascular disease through the systemic secretion of adipokines. We therefore evaluated the relation of epicardial fat thickness, serum levels of epicardial fat-related adipokines (chemerin and vaspin), and CFR in patients with NAFLD. Methods: We investigated 54 patients with biopsy-proven NAFLD and 56 age- and sex-matched controls. CFR and epicardial fat thickness (EFT) were measured by transthoracic echocardiography. Serum levels of chemerin and vaspin were measured by ELISA. Results: EFT was significantly higher (0.64 ± 0.13 vs. 0.54 ± 0.10 cm, P < 0.001) and CFR significantly lower (2.11 ± 0.45 vs. 2.52 ± 0.62, P < 0.001 ) in patients with NAFLD than in controls. Serum levels of vaspin and chemerin were both significantly increased in patients with NAFLD compared with controls. Stepwise regression analysis showed that EFT (β = ―0.53, t = ―3.7, P < 0.001), serum vaspin levels (β = ―0.30, t = ―2.5, P=0.014), and liver fibrosis (β = ―0.31, t = ―2.11, P=0.041 in the order they entered into the model, were independent predictors of CFR in NAFLD patients. Conclusion: Our data suggest the presence of a complex interplay between EFT, serum vaspin, and liver histology in promoting an impaired hyperemic stimulation of coronary blood flow in patients with NAFLD.