Association between body mass index and liver disorders:: an epidemiological study

Background/Aims: 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 greater than or equal to30 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. (C) 2002 European Association for the Study of the Liver. Published by Elsevier Science B.V. All rights reserved.