Prevalence of Non-alcoholic Fatty Liver Disease in Iran: A Systematic Review and Meta-analysis

Non-alcoholic fatty liver disease (NAFLD) has a benign course in several patients; however, a serious form of this disease can turn into liver failure, liver cirrhosis, and hepatocellular carcinoma.

This study aims to estimate the prevalence of NAFLD in Iran.

We searched the following databases from January 2000 to December 2022: Scopus, Pubmed/Medline, Embase, Web of Sciences, the Cochrane Library, and Google Scholar also a number of Iranian databases, namely MagIran, SID, and Elmnet. Additionally, the quality of the included studies was evaluated through the Newcastle-Ottawa Scale. We estimated heterogeneity between studies using the I² statistic. Furthermore, we performed a synthesis of prevalence estimates through the random-effects DerSimonian and Laird model across the included studies with a 95% confidence interval. To assess the publication bias, we also used Egger's test.

Thirty-one studies were eligible for inclusion. The overall number of participants in the present study was 41,971. The overall prevalence of NAFLD in Iran was 33% [CI: 27-37%], with I2 = 99.7% (P < 0.01). The prevalence was 35% [CI: 27-43%] and 37% [CI: 27-47%] in males and females, respectively. We used Egger's test, and no significant publication bias was identified in the overall prevalence (P = 0.45).

According to the results of this study, the prevalence of NAFLD in Iran is not only high but alsoa growing trend. Effective strategies for changing lifestyles, changing eating habits, and encouraging physical activities among Iranians are recommended. Also, providing screening tests, especially among high-risk groups, has a significant effect on early diagnosis and NAFLD control.