Correlation between the non-alcoholic fatty liver disease and common carotid artery intimal medial thickness in patients attending a tertiary care hospital

Introduction: Non-alcoholic fatty liver disease (NAFLD) is an emerging common non communicable disease, worldwide. It is characterized by accumulation of excess fat within the liver cells which could progress into cirrhosis. Although the gold standard method for diagnosis of this condition is by liver biopsy, the ultrasonography can accurately diagnose it. Atherosclerosis is characterized by the presence of intimal lesions which manifest indirectly as increased intimal medial thickness of an artery. Several studies have shown greater intima-media thickness in patients with NAFLD, but there are no studies reported in Sri Lanka. Hence, this study is done to assess the correlation between the stage of NAFLD and common carotid artery intimal medial thickness (CIMT) in a tertiary care hospital in Sri Lanka. Objectives: The general objective of this study is to evaluate the correlation between the stage of non-alcoholic fatty liver disease and common carotid artery intimal medial thickness in patients attending Department of Radiology Teaching Hospital Peradeniya. The specific objectives of this study are to describe the socio-demographic profile of the patients with NAFLD, to calculate the body mass index (BMI) of the patients with NAFLD and to determine the correlation between the stage of NAFLD and CIMT of the patients with NAFLD. Methods: This prospective correlational study was conducted after getting ethical clearance from Faculty of Medicine, University of Peradeniya. 201 patients who fulfill the pre- set exclusion and inclusion criteria were recruited for the study. The main exclusion criteria for this study were patients having chronic illness, communicable diseases and hepatic diseases. Patients who give consent and having any degree of fatty liver were included for the study. Sonographic evaluation of grade of fatty liver and B/L CIMT was done and recorded. Consecutive sampling method was used. Descriptive statistics were used to describe the socio-demographic profile and body mass index. Spearman’s rank order correlation test was used to determine the correlation between the stage of NAFLD and CIMT at 95% confidence interval. Results: The age range of the study population was 23 years to 79 years (Mean = 41.77, SD=12.93) and majority belonged to primary working age group (25- 54 years; 75%). Majority of patients were males (56.2%). Average BMI was 25.18kgm-2 (SD=4.37) and 45% of patients were obese. Majority of patients had grade II fatty liver (57.7%). A significant correlation was found between the age and bilateral CIMT.(p value <0.001). Average CIMT in right and left side were 0.075 cm (SD= 0.009) and 0.077 cm (SD= 0.01) respectively. Average R/ CIMT in males was 0.074 cm and that of in females were 0.077 cm. Average L/ CIMT in males were 0.076 cm and that of in females were 0.078 cm. A statistically significant difference was found between means of R/ CIMT in male and females (p value 0.045) but no statistically significant difference was found on L/side (p value 0.44). There was no statistically significant correlation between the grade of fatty liver with right CIMT (correlation coefficient= 0.025, p = 0.730) or left CIMT (correlation coefficient = 0.128, p = 0.072). Conclusion: Majority of patients with NAFLD were males who belonged to primary working age group. 45% of study population were obese. Majority of patients had grade II fatty liver. There is a significant correlation between the age and CIMT. However there was no correlation between the grade of NAFLD and right or left CIMT.