title: Association between body mass index and liver disorders: an epidemiological study.
abstract: OBJECTIVE
  Cross-sectional studies showed an association between obesity and liver disorders. Information on incidence rates from epidemiological studies is scarce.
  
  
  METHODS
  To explore the association between body mass index (BMI) and incident liver disorders, we conducted a follow-up study with a nested case-control analysis using the UK-based General Practice Research Database. The study population encompassed normal weight (BMI <25 kg/m(2)), pre-obese (BMI 25-29.9 kg/m(2)) or obese (BMI > or =30 kg/m(2)) subjects aged 20-79 years, matched on age, sex and general practice attended.
  
  
  RESULTS
  Within the study population of 207,630 subjects, we identified 2718 cases of newly diagnosed liver disorder, of whom 1524 (56.1%) had known predisposing conditions. The incidence rates were 2.48 (95% CI 2.31-2.66)/1000 person-years (py) in normal weight, 2.91 (95% CI 2.72-3.11)/1000 py in pre-obese, and 3.83 (95% CI 3.62-4.07)/1000 py in obese subjects. In the nested case-control analysis, the adjusted odds ratio (OR) for obese, as compared to normal weight subjects, was 1.2 (95% CI 1.1-1.4). The OR for idiopathic cases (without known risk factors for liver disorders) was 1.3 (95% CI 1.1-1.6).
  
  
  CONCLUSIONS
  The study indicates that obesity is associated with a modest increase in the incidence of newly diagnosed liver disorder.
authors.affiliation: Basel Pharmacoepidemiology Unit, Division of Clinical Pharmacology and Toxicology, Department of Internal Medicine, University Hospital Basel, Petersgraben 4, 4031 Basel, Switzerland. christoph.meier@unibas.ch
authors.forename: Christoph R
authors.initials: CR
authors.lastname: Meier
authors.forename: Stephan
authors.initials: S
authors.lastname: Krähenbühl
authors.forename: Raymond G
authors.initials: RG
authors.lastname: Schlienger
authors.forename: Hershel
authors.initials: H
authors.lastname: Jick
mesh_terms: D000328:Adult; D000368:Aged; D015992:Body Mass Index; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D015994:Incidence; D008107:Liver Diseases / Q000453:epidemiology* / Q000209:etiology; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000150:complications; D016017:Odds Ratio