Abstract
BACKGROUND: The relationship between apolipoprotein C3 (APOC3) gene polymorphisms and nonalcoholic fatty liver disease (NAFLD) risk has been investigated in many studies, with inconclusive findings. This meta-analysis evaluated the effect of APOC3 promoter region polymorphisms (-455T/C and -482C/T) on NAFLD susceptibility. METHODS: A comprehensive search of eligible studies up to October 2020 was performed on Medline, Embase, Web of Science, and Google Scholar databases. No restriction was imposed on language, publication date, or publication status. Odds ratios (ORs) with their 95% confidence intervals (CIs) were calculated to assess the combined effect sizes. The levels of heterogeneity, sensitivity, subgroup, and publication bias were analyzed subsequently. RESULTS: This meta-analysis included eight studies, consisting of 1,511 patients with NAFLD and 1,900 controls fulfilling the inclusion criteria and exclusion criteria. The pooled analysis showed significant associations between APOC3 -455T/C polymorphism and NAFLD risk in allelic (OR = 1.33; 95% CI = 1.05-1.67), dominant (OR = 1.34; 95% CI = 1.04-1.72), and recessive (OR = 1.60; 95% CI = 1.06-2.40) models. Ethnicity-based stratification showed that -455T/C polymorphism was significantly associated with NAFLD risk in the non-Asian but not in the Asian population. No association was evident between -482C/T polymorphism and NAFLD risk. CONCLUSION: Our findings suggest that APOC3 promoter region polymorphism -455T/C may be associated with NAFLD risk in the non-Asian but not in the Asian population. Additional studies with other functional polymorphisms are needed to discover APOC3 gene effects on NAFLD.