The Prevalence of Non-Alcoholic Fatty Liver Disease in Iranian Children and Adult Population: A Systematic Review and Meta-Analysis

Background: Non-alcoholic fatty liver disease (NAFLD) is the world's most common etiology of chronic liver disease. In this systematic review and meta-analysis, we estimated the prevalence of NAFLD in the Iranian children and adult population.Methods: A comprehensive search of five international databases, including PubMed, ISI/WOS, ProQuest, Scopus, and Google Scholar, was done from inception to Nov 2022. Studies on NAFLD patients and their risk factors were selected for meta-analysis. The quality of the included studies was assessed by The Joanna Briggs Institute (JBI) Critical Appraisal Checklist for cross-sectional, and cohort studies. The heterogeneity between studies was investigated using Cochran test and I2 statistics. Random and fixed effect models were used for heterogenic and non-heterogenic studies, respectively. We used Comprehensive Meta-Analysis version 3 for conducting meta-analysis. Results: Twenty studies were finally included. The total prevalence of NAFLD in children, boys, and girls was 6.7% (95% CI: 0.02-0.18), 12.5% (95% CI: 0.04-0.29) and, 10.1% (95% CI: 0.04-0.21), respectively. The total prevalence of NAFLD in obese children, obese boys, and obese girls was 42% (95% CI: 0.18-0.69), 44% (95% CI: 0.13-0.80), and 33 % (95% CI: 0.13-0.62), respectively. The total prevalence of NAFLD in adults was 36.9% (95% CI: 0.31-0.42). The prevalence of NAFLD in men and women was 33.8% (95% CI: 0.27-0.41) and 29.9% (95% CI: 0.21-0.40), respectively.Conclusion: NAFLD prevalence in Iranian adults and obese children is considerable; however, data about the children population was insufficient.