Alanine aminotransferase and gamma-glutamyl transferase are associated with the metabolic syndrome but not with angiographically determined coronary atherosclerosis

Background: Recently, elevated liver enzymes have attracted great interest as potential novel markers of cardiovascular risk. Their association with angiographically determined coronary artery disease (CAD) is unknown. Methods: We enrolled 1000 consecutive patients undergoing coronary angiography for the evaluation of suspected or established stable CAD. The metabolic syndrome (MetS) was defined according to ATP-III criteria; significant CAD was diagnosed in the presence of coronary stenoses with lumen narrowing >50%. Results: Serum alanine aminotransferase (ALT), the ALT/aspartate aminotransferase (AST) ratio, and serum gamma-glutamyl transferase (GGT) were significantly higher in patients with the MetS than in subjects without the MetS (34 +/- 21 vs. 29 +/- 20 U/l; p<0.001, 1.16 +/- 0.39 vs. 1.00 +/- 0.36 U/l, p<0.001; and 53 +/- 88 vs. 43 +/- 57 U/l, p=0.001, respectively) but were similar in patients with significant CAD as in those who did not have significant CAD at angiography (p=0.592; p=0.731, and p=0.716, respectively). Analysis of covariance after multivariate adjustment including alcohol consumption confirmed that ALT, ALT/AST ratio, and GGT were significantly and independently associated with the MetS but not with significant CAD. Conclusions: ALT, the ALT/AST ratio, and GGT are associated with the MetS but not with angiographically determined coronary atherosclerosis. (C) 2008 Elsevier B.V. All rights reserved.