Association of Non-Alcoholic Fatty Liver Disease with Increased Carotid Intima-Media Thickness Considering Other Cardiovascular Risk Factors

Background: Non-alcoholic fatty liver disease (NAFLD) is the most common liver disease (6% - 35%) and is associated with cardiovascular risk factors and metabolic syndromes (age, diabetes, hyperlipidemia, hypertension and smoking). Hereby, we evaluated the association of increased carotid intima-media thickness (IMT) with NAFLD considering other cardiovascular risk factors to see if NAFLD is independently associated with increased carotid IMT. Patients and Methods: Totally 300 patients [150 NAFLD and 150 normal] who were referred to four academic referral hospitals were enrolled. Patients with a history of alcohol use, hepatitis, HIV, chemotherapy and other organ failures were excluded. A single radiologist performed abdominal sonographies [3 - 5 MHz probe] and carotid sonography [7.5 MHz probe] (measured the posterior wall of both common carotids and calculated the mean value). NAFLD was diagnosed based on sonographic findings in the absence of acute or chronic liver and kidney diseases and malignancies. Results: The mean age was 51.2 ± 14.8 [20 - 97] and 184 [61.3%] were male. Mean IMT was greater in patients with diabetes, hypertension, hyperlipidemia and NAFLD [all Ps < 0.001] and these variables with age were statistically significant in univariate models for estimating IMT. Among NAFLD patients, 38 [25.3%] had increased IMT [unilateral or bilateral; considering 0.8 as cutoff point] while this frequency was 8 [%5.3] among normal subjects [P < 0.001, odds ratio = 6, 95% confidence interval (CI) = 2.7 - 13.4]. In multivariate regression models [IMT as dependent variable], NAFLD, age and hyperlipoproteinemia (HLP) were independent significant variables in linear model [R2 = 0.41] and NAFLD showed highest odds ratio [16.4] among significant variables [age, body mass index (BMI), NAFLD and HLP] in the logistic model. Conclusion: Increase carotid IMT is highly associated with NAFLD independent of other cardiovascular risk factors and should be considered in these patients.