Aortic elastic properties in nonalcoholic fatty liver disease

Abstract

Recent studies have shown that patients with nonalcoholic fatty liver disease (NAFLD) have an increased risk of developing cardiovascular disease. Aortic stiffness, an early marker of arteriosclerosis, is associated with cardiovascular mortality. In this study, the aortic elastic properties of nondiabetic, normotensive NAFLD patients were evaluated. Thirty-five patients with NAFLD and 30 age-matched and sex-matched healthy controls were enrolled. Aortic distensibility, aortic strain, aortic stiffness index (ASI), left ventricular mass index (LVMI), homeostasis model assessment of insulin resistance (HOMA-IR) and fasting lipid parameters were assessed in both the groups. ASI was higher in NAFLD patients (7.1+/-2.0) than in the control group (3.8+/-1.0) (P<0.01). Aortic distensibility and aortic strain were also significantly decreased in NAFLD patients as compared with the control group (2.9+/-0.7 cm/dyn vs. 6.3+/-2.4 cm/dyn, P<0.0001 and 7.1+/-1.7 vs. 14.5+/-4.0, P<0.0001, respectively). Although ASI was significantly correlated with age, HOMA-IR, waist circumference, body mass index and LVMI, a stepwise multiple linear regression analysis showed that HOMA-IR and LVMI were the only variables associated with ASI index [(standardized beta coefficient= 0.41, P=0.004, overall R=0.17) and (standardized beta coefficient=0.31, P=0.02, overall R=0.10), respectively]. Our data suggest that aortic elasticity is significantly impaired and is also associated with insulin resistance and LVMI in NAFLD patients, which may contribute to the relationship between NAFLD and the increased risk of cardiovascular disease among these patients.