Effect of non-alcoholic fatty liver disease on carotid artery intima-media thickness as a risk factor for atherosclerosis

AIM: This study aimed to evaluate the effect of NAFLD on CIMT as a risk factor for atherosclerosis. BACKGROUND: The prevalence of non-alcoholic fatty liver disease (NAFLD) is increasing worldwide due to rise of obesity and diabetes mellitus (DM) prevalence. Non-invasive assessment of carotid intima-media thickness (CIMT) by high-resolution carotid B-mode ultrasonography is widely used for determining the atherosclerosis. PATIENTS AND METHODS: In this case-control setting, 151 subjects were categorized in three groups: group I including 49 patients with NAFLD and DM; group II including 50 non-diabetic NAFLD patients; and the control including 52 normal subjects as group III. The right and left CIMTs and its maximum reading (CIMT(max)) were measured by a skilled sonographist blind to the groups. The sonographic grading of the NAFLD was determined in group I and II. RESULTS: Median CIMT(max) was significantly higher in group I comparing with group II and control group (p<0.001). This difference between group I and group II was not significant after adjusting for age and history of hypertension and hyperlipidemia (p=0.089). After controlling the confounders, there was statistical significant between group I and group II with the control group (p<0.05). There was no significant difference in median maximal thickness of intima-media in the carotid of group I compare to group II in patients with and without elevated liver enzymes (in both groups, 0.6 mm, p= 0.402). CONCLUSION: Based on our findings, there is a significant association between the presence of NAFLD and atherosclerosis. This association was independent to the DM presence. The grade of NAFLD and elevated liver function tests had no effect on severity of atherosclerosis.