Flow-mediated dilatation deficiency of the brachial artery and increased carotid intimal thickness in non-alcoholic fatty liver disease

Abstract

Aims: This study aimed to evaluate endothelial dysfunction and vascular changes in non-alcoholic fatty liver disease (NAFLD) patients by measuring carotid intima-media thickness (C-IMT) and flow-mediated dilation (FMD). Methods: This prospective observational cohort study included 51 biopsy-proven NAFLD patients and 21 healthy controls. Endothelial function was assessed using high-resolution ultrasonography to measure brachial artery FMD and C-IMT. Patients with hepatotoxic drug use, significant alcohol consumption, or other liver diseases were excluded. Demographic data, body- mass index (BMI), and waist circumference were recorded. Statistical analyses were conducted using SPSS, with significance set at p<0.05. Results: NAFLD patients showed significantly higher BMI, waist circumference, and diastolic blood pressure compared to controls. The mean C-IMT was elevated in NAFLD patients (0.67±0.09 mm) compared to controls (0.52±0.11 mm; p<0.001), and FMD was significantly reduced in NAFLD patients (7.3±4.8%) compared to controls (16.5±7.1%; p<0.001). FMD and C-IMT values were lower in NASH cases than in simple steatosis. A significant negative correlation was observed between FMD and BMI, waist circumference, and C-IMT values. Conclusion: NAFLD patients, particularly those with NASH, exhibit significant endothelial dysfunction characterized by reduced FMD and increased C-IMT, indicating early atherosclerosis. These findings suggest that endothelial dysfunction increases with progression of NAFLD. Early recognition of vascular changes in NAFLD patients could facilitate timely interventions to reduce cardiovascular risk and disease progression.