Global epidemiology of lean non‐alcoholic fatty liver disease: A systematic review and meta‐analysis
Year: 2020
Type: review
Study designs: Systematic Review, Meta-Analysis
Abstract: BACKGROUND AND AIM: Lean non-alcoholic fatty liver disease (NAFLD) is a potentially metabolically unhealthy state that refers to NAFLD occurring in non-overweight/nonobese subjects. Yet its global epidemiology and metabolic characteristics are not extensively elucidated. METHODS: PubMed, EMBASE, Web of Science and Cochrane databases were searched for eligible studies until January 2020. Random-effects/fixed-effects models were used to estimate the global prevalence of lean NAFLD and to compare clinical characteristics among lean non-NAFLD, lean NAFLD, and overweight/obese NAFLD subjects. "Lean" NAFLD was defined by ethnic-specific body mass index measurements in the normal range. Meta-regression and subgroup analyses were performed to determine potential sources of heterogeneity. RESULTS: A total of 33 observational studies were included with 205 307 individuals from 14 countries. The global prevalence of lean NAFLD was 4.1% (95% confidence interval [CI]: 3.4-4.8%). In lean subjects, the prevalence of NAFLD was 9.7% (95% CI: 7.7-11.8%). The prevalence of lean NAFLD with diabetes, hypertension, metabolic syndrome, dyslipidemia, or central obesity was 0.6% (95% CI: 0.4-0.9%), 1.8% (95% CI: 1.2-2.5%), 1.4% (95% CI: 1.0-1.9%), 2.8% (95% CI: 1.9-3.7%), and 2.0% (95% CI: 1.6-2.4%), respectively. The prevalence of lean NAFLD showed an upward trend between 1988 and 2017. Asian individuals had the highest prevalence of lean NAFLD (4.8%, 95% CI: 4.0-5.6%). Middle-aged people (45-59 years old) had the highest prevalence of lean NAFLD (4.4%, 95% CI: 3.2-5.5%). The prevalence of metabolic complications in lean non-NAFLD, lean NAFLD, and overweight/obese NAFLD groups increased sequentially. CONCLUSIONS: Lean NAFLD occurs with metabolic complications and is not an uncommon condition. The highest prevalence of lean NAFLD occurs in middle-aged individuals of Asian countries.
DOI: 10.1111/jgh.15156
Institutions: Tongde Hospital of Zhejiang Province, First Affiliated Hospital of Wenzhou Medical University, Azienda Ospedaliera Universitaria Integrata Verona, Southampton General Hospital, University Hospital Southampton NHS Foundation Trust, National Institute for Health and Care Research, NIHR Southampton Biomedical Research Centre, Wenzhou Medical University
Language: English
Subfield: Epidemiology
Field: Medicine
Domain: Health Sciences
Open Access status: green
Awards: G1981077784, G3290609987, G4492105040
OpenAlex ID: W3037057530
