The association between nonalcoholic fatty liver disease, metabolic syndrome and arterial stiffness in nondiabetic, nonhypertensive individuals

Objectives: To assess the relationship between nonalcoholic fatty liver disease (NAFLD) and arterial stiffness in nondiabetic, nonhypertensive individuals with and without metabolic syndrome (MetS). Methods: Hepatic ultrasound and brachial-ankle pulse wave velocity (baPWV) were investigated in 4,467 individuals. The subjects were classified into normal PWV and increased PWV (≥1,366 cm/s) groups, and divided into 2 groups (non-NAFLD vs. NAFLD groups) and 3 groups (non-, mild and moderate-to-severe NAFLD groups), respectively. Results: The overall prevalence of NAFLD was 37.3% and the NAFLD group had higher levels of baPWV (control vs. NAFLD, 1,363 ± 210.3 vs. 1,388 ± 235.9 cm/s, p < 0.001). On multivariate regression analysis, NAFLD was independently associated with increased baPWV (≥1,366 cm/s), irrespective of multiple covariates (OR 1.237 and 95% CI 1.050-1.458). Subgroup analyses revealed that there was a significant association between NAFLD and baPWV only in individuals without MetS (OR 1.267 and 95% CI 1.065-1.507). The multivariate linear regression models for the overall study population and for individuals without MetS also revealed a significant association between NAFLD and the absolute value of baPWV; however, the result for individuals with MetS did not. Conclusions: Our results indicate that the presence and the degree of NAFLD are associated with arterial stiffness in nonhypertensive, nondiabetic individuals, especially in those individuals without MetS.