Prevalence of non-alcoholic fatty liver disease in regional Victoria: a prospective population-based study

Objectives: To investigate the prevalence of non-alcoholic fatty liver disease (NAFLD) and its risk factors in regional Victoria. Design: Prospective cross-sectional observational study (sub-study to CrossRoads II health study in Shepparton and Mooroopna). Setting: Four towns (populations, 6300-49 800) in the Goulburn Valley of Victoria. Participants: Randomly selected from households selected from residential address lists provided by local government organisations for participation in the CrossRoads II study. Main outcome measures: Age-and sex-adjusted estimates of NAFLD prevalence, defined by a fatty liver index score of 60 or more in people without excessive alcohol intake or viral hepatitis. Results: A total of 705 invited adults completed all required clinical, laboratory and questionnaire evaluations of alcohol use (participation rate, 37%); 392 were women (56%), and their mean age was 59.1 years (SD, 16.1 years). Of the 705 participants, 274 met the fatty liver index criterion for NAFLD (crude prevalence, 38.9%; age-and sex-standardised prevalence, 35.7%). The mean age of participants with NAFLD (61 years; SD, 15 years) was higher than for those without NAFLD (58 years; SD, 16 years); a larger proportion of people with NAFLD were men (50% v 41%). Metabolic risk factors more frequent among participants with NAFLD included obesity (69% v 15%), hypertension (66% v 48%), diabetes (19% v 8%), and dyslipidaemia (63% v 33%). Mean serum alanine aminotransferase levels were higher (29 U/L; SD, 17 U/L v 24 U/L; SD, 14 U/L) and mean median liver stiffness greater (6.5 kPa; SD, 5.6 kPa v 5.3kPa; SD, 2.0 kPa) in participants with NAFLD. Conclusion: The prevalence of NAFLD among adults in regional Victoria is high. Metabolic risk factors are more common among people with NAFLD, as are elevated markers of liver injury.