Epidemiology of nonalcoholic fatty liver disease in Europe: a systematic review and meta-analysis

BACKGROUND: Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease in the developed countries. The aim of this study was to evaluate the NAFLD prevalence in European adults and children/adolescents of the general population and specific subgroups. METHOD: Search for all articles published between 01/1990-06/2019 reporting NAFLD prevalence from European countries. RESULTS: Nineteen studies with adults and 9 with children/adolescents were included. Pooled NAFLD prevalence in adults was 26.9%, being higher in studies using ultrasonography (27.2%) or fatty liver index (FLI) (30.1%) than liver biochemical tests (19.1%) and without differences between Mediterranean and non-Mediterranean countries or publication periods. Pooled NAFLD prevalence was higher in men than women (32.8% vs. 19.6%) and in patients with than those without metabolic syndrome (75.3% vs. 17.9%) or any of its components (always P<0.01). Ultrasound and FLI performed equally in estimating NAFLD prevalence in most subgroups. A higher prevalence was reported using FLI in obese and in diabetic patients, whereas a higher prevalence was observed with ultrasound in non-obese patients and in individuals without metabolic syndrome. NAFLD prevalence was 2.7% in unselected and 31.6% in obese/overweight children/adolescents. CONCLUSIONS: NAFLD prevalence exceeds 25% in European adults, being higher in those with metabolic syndrome component(s)-related comorbidities. It remains low in unselected NAFLD population, but increased in overweight/obese European children/adolescents, particularly from Mediterranean countries.