Causal effects from nonalcoholic fatty liver disease on cholelithiasis: A mendelian randomization study

Background and AimsBoth nonalcoholic fatty liver disease (NAFLD) and cholelithiasis are highly prevalent hepatobiliary diseases with risk of progression into severe outcomes. Considering the close relationship between liver and gallbladder in anatomy and physiology, a potential causal relationship between NAFLD and cholelithiasis has been speculated.MethodsMendelian randomization (MR) was employed using genome-wide association study (GWAS) summary statistics in Million Veteran Program (MVP) for NAFLD, and statistics in UK biobank for cholelithiasis.ResultsOur results demonstrate that NAFLD has a causal effect on cholelithiasis risk (OR, 1.003; 95%CI, 1.000-1.006; p = 0.03). We also performed the sensitivity analysis and heterogeneity test to ensure the accuracy of outcome and avoid the reverse causality.ConclusionNAFLD should be regarded as a potential pathogenic factor in pathogenesis study of cholelithiasis, and be considered in assessment and treatment of cholelithiasis.