The global epidemiology of NAFLD and NASH in patients with type 2 diabetes: A systematic review and meta-analysis

[Display omitted] •Prevalence of NAFLD in patients with type 2 diabetes mellitus is more than 2-fold higher than in the general population.•The overall prevalence of NAFLD among patients with type 2 diabetes mellitus is 55.5%.•The global prevalence of non-alcoholic steatohepatitis among patients with type 2 diabetes is 37.3%.•Of the patients with NAFLD and type 2 diabetes mellitus who undergo liver biopsy, 17% have advanced fibrosis. Although non-alcoholic fatty liver disease (NAFLD), non-alcoholic steatohepatitis (NASH) and NASH with advanced fibrosis are closely associated with type 2 diabetes mellitus (T2DM), their global prevalence rates have not been well described. Our aim was to estimate the prevalence of NAFLD, NASH, and advanced fibrosis among patients with T2DM, by regions of the world. We searched for terms including NAFLD, NASH and T2DM in studies published from January 1989 to September 2018, using PubMed, Ovid MEDLINE®, EMBASE and Web of Science. Strict exclusion criteria were applied. Regional and global mean prevalence weighted by population size in each country were estimated and pooled using random-effects meta-analysis. Potential sources of heterogeneity were investigated using stratified meta-analysis and meta-regression. Among 80 studies from 20 countries that met our inclusion criteria, there were 49,419 individuals with T2DM (mean age 58.5 years, mean body mass index 27.9 kg/m2, and males 52.9%). The global prevalence of NAFLD among patients with T2DM was 55.5% (95% CI 47.3–63.7). Studies from Europe reported the highest prevalence (68.0% [62.1–73.0%]). Among 10 studies that estimated the prevalence of NASH, the global prevalence of NASH among individuals with T2DM was 37.3% (95% CI 24.7–50.0%). Seven studies estimated the prevalence of advanced fibrosis in patients with NAFLD and T2DM to be 17.0% (95% CI 7.2–34.8). Meta-regression models showed that geographic region and mean age (p