Prevalence and risk factors of non-alcoholic fatty liver disease in southwest Iran: a population-based case-control study

Aim of the study
Few population-based studies have been conducted to report the prevalence of non-alcoholic fatty liver disease (NAFLD) and determine its risk factors in Iran, particularly in Shahrekord, southwest Iran. The main aim of this population-based, case-control study was to determine the prevalence of NAFLD and its potential risk factors in an Iranian population-based cohort study in Shahrekord, Iran.

Material and methods
We compared 1153 cases with NAFLD at 35 to 70 years to 1153 frequency-matched NAFLD-free controls from a population-based Shahrekord cohort study. Data collection and assessed risk factors (demographics, anthropometrics, clinical and biochemical factors, and laboratory tests) were performed based on the Shahrekord cohort study protocol. Chi-square test, stepwise selection with backward likelihood ratio, logistic regression and log-binomial regression model with 95% confidence interval were performed to determine risk factors with significant effects on NAFLD.

Results
In this study, the mean (± standard deviation) age of the participants was 50.23 (±8.70) years. The prevalence of NAFLD and metabolic syndrome with 95% confidence interval were 16.47% (15.61-17.36%) and 32.74% (30.83-34.70%), respectively. There was a significant difference in the frequency of waist circumstance, triglycerides, body mass index, blood pressure, and alanine aminotransferase between cases and controls (p < 0.001). According to log-binomial model results, socioeconomic status, hypertension, diabetes, and physical activity were significantly associated with NAFLD.

Conclusions
Our findings have important clinical and public health implications in southwest Iran for monitoring the prevalence of NAFLD and important risk factors to manage, screen, prevent, and reduce NAFLD and related factors.