Association Between The Severity Of Nonalcoholic Fatty Liver Disease And The Risk Of Colorectal Neoplasms:Meta-analysis

Background and aimNonalcoholic fatty liver disease(NAFLD)is becoming a worldwide public health problem,causing considerable health and economic burden in the world.Therefore,it is an important issue and task to reduce the incidence and mortality of hepatic and extrahepatic diseases in patients with NAFLD to extend their life expectancy and improve the quality of life.In recent years,an increasing number of studies have found that NAFLD is significantly associated with the risk of colorectal neoplasms.However,there is still no consensus on whether the severity of NAFLD is also associated with the risk of colorectal neoplasms.This study aims to explore the relationship between the severity of NAFLD and the risk of colorectal neoplasms through the extraction and summary analysis of the original study data,to achieve the early detection of colorectal neoplasms in patients with NAFLD,reduce the incidence and mortality of colorectal neoplasms and extend their life expectancy.MethodsLiterature searches were performed in the PubMed,Embase and Web of Science databases using various combinations of subject terms and free words related to"Nonalcoholic Fatty Liver Disease" and "Colorectal Neoplasms".The searches were conducted from database establishment to February 1,2023.Two researchers independently conducted literature searches and screening and performed quality evaluation and data extraction of the literature meeting the inclusion criteria.A random effects model was used to calculate the combined ratio(OR)and the corresponding 95%confidence interval(95%CI).Finally,subgroup analysis was performed to identify potential sources of heterogeneity.ResultsA total of 14 publications were eventually included in this study,with relevant data from 38,047 patients.Standard Meta-analysis results showed that the risk of colorectal adenomas(OR=1.74,95%CI=1.14-2.64,I2=71.6%,P=0.00<0.05)and advanced colorectal neoplasms was higher in patients with more severe NAFLD than in those with less severe NAFLD(OR=1.77,95%CI=1.14-2.76,I2=84.4%,P=0.00<0.05).Subgroup analysis showed that in the cross-sectional study,patients with more severe NAFLD had a higher prevalence of colorectal adenomas(OR=1.62,95%CI=1.06-2.47,I2=56.0%,P=0.045)and advanced colorectal neoplasms(OR=2.36,95%CI=1.30-4.28,I2=76.1%,P=0.002).While,in the cohort study,no significant differences were found in the incidence of colorectal adenomas(OR=1.65,95%CI=0.54-5.07)and advanced colorectal neoplasms(OR=1.08,95%CI=0.90-1.29)between patients with less severe NAFLD and more severe NAFLD.When the degree of liver fibrosis was used to assess the severity of NAFLD,the results showed that patients with advanced liver fibrosis had a higher risk of colorectal adenomas(OR=1.45,95%CI=1.10-1.91)and advanced colorectal neoplasms(OR=1.94,95%CI=1.06-3.55)than patients without advanced liver fibrosis.While,when the severity of NAFLD was assessed using the degree of hepatic steatosis,the results showed there was no significant difference in the incidence of colorectal adenomas and advanced colorectal neoplasms between patients with NAFLD with mild hepatic steatosis and those with more severe hepatic steatosis.When the presence or absence of steatohepatitis was used to assess the severity of NAFLD,the results showed that there was no significant difference in the risk of colorectal adenomas and advanced colorectal neoplasms between patients with simple steatohepatitis and those with nonalcoholic steatohepatitis.After adjusting for important confounders such as smoking,alcohol,obesity,hypertension,diabetes,aspirin use,history of early colorectal adenomas,and family history of colorectal cancer,the risk of colorectal adenomas(aOR=3.04,95%CI=1.53-6.07)and advanced colorectal neoplasms(aOR=2.24,95%CI=1.25-4.01)in patients with more severe NAFLD remained higher than those with less severe NAFLD.Conclusion1.There is a positive correlation between NAFLD severity and the risk of colorectal adenomas and advanced colorectal neoplasms.2.Patients with NAFLD with advanced liver fibrosis have a higher risk of colorectal adenomas and advanced colorectal neoplasms than patients with NAFLD without advanced liver fibrosis.