title: Characterisation of liver fat in the UK Biobank cohort.
abstract: Non-alcoholic fatty liver disease and the risk of progression to steatohepatitis, cirrhosis and hepatocellular carcinoma have been identified as major public health concerns. We have demonstrated the feasibility and potential value of measuring liver fat content by magnetic resonance imaging (MRI) in a large population in this study of 4,949 participants (aged 45-73 years) in the UK Biobank imaging enhancement. Despite requirements for only a single (≤3min) scan of each subject, liver fat was able to be measured as the MRI proton density fat fraction (PDFF) with an overall success rate of 96.4%. The overall hepatic fat distribution was centred between 1-2%, and was highly skewed towards higher fat content. The mean PDFF was 3.91%, and median 2.11%. Analysis of PDFF in conjunction with other data fields available from the UK Biobank Resource showed associations of increased liver fat with greater age, BMI, weight gain, high blood pressure and Type 2 diabetes. Subjects with BMI less than 25 kg/m2 had a low risk (5%) of high liver fat (PDFF > 5.5%), whereas in the higher BMI population (>30 kg/m2) the prevalence of high liver fat was approximately 1 in 3. These data suggest that population screening to identify people with high PDFF is possible and could be cost effective. MRI based PDFF is an effective method for this. Finally, although cross sectional, this study suggests the utility of the PDFF measurement within UK Biobank, particularly for applications to elucidating risk factors through associations with prospectively acquired data on clinical outcomes of liver diseases, including non-alcoholic fatty liver disease.
authors.affiliation: Perspectum Diagnostics, Oxford, United Kingdom.|Department of Life Sciences, University of Westminster, London, United Kingdom.
authors.forename: Henry R
authors.identifier: http://orcid.org/0000-0002-3362-1204
authors.initials: HR
authors.lastname: Wilman
authors.affiliation: Perspectum Diagnostics, Oxford, United Kingdom.
authors.forename: Matt
authors.initials: M
authors.lastname: Kelly
authors.affiliation: UK Biobank, Stockport, United Kingdom.
authors.forename: Steve
authors.initials: S
authors.lastname: Garratt
authors.affiliation: Division of Brain Sciences and Centre for Neurotechnology, Imperial College London, United Kingdom.
authors.forename: Paul M
authors.initials: PM
authors.lastname: Matthews
authors.affiliation: Perspectum Diagnostics, Oxford, United Kingdom.
authors.forename: Matteo
authors.initials: M
authors.lastname: Milanesi
authors.affiliation: Perspectum Diagnostics, Oxford, United Kingdom.
authors.forename: Amy
authors.initials: A
authors.lastname: Herlihy
authors.affiliation: Perspectum Diagnostics, Oxford, United Kingdom.
authors.forename: Micheal
authors.initials: M
authors.lastname: Gyngell
authors.affiliation: Perspectum Diagnostics, Oxford, United Kingdom.|OCMR, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, United Kingdom.
authors.forename: Stefan
authors.initials: S
authors.lastname: Neubauer
authors.affiliation: Department of Life Sciences, University of Westminster, London, United Kingdom.
authors.forename: Jimmy D
authors.initials: JD
authors.lastname: Bell
authors.affiliation: Perspectum Diagnostics, Oxford, United Kingdom.
authors.forename: Rajarshi
authors.initials: R
authors.lastname: Banerjee
authors.affiliation: Department of Life Sciences, University of Westminster, London, United Kingdom.
authors.forename: E Louise
authors.initials: EL
authors.lastname: Thomas
mesh_terms: D000273:Adipose Tissue / Q000000981:diagnostic imaging* / Q000473:pathology; D000367:Age Factors; D000368:Aged; D018070:Biological Specimen Banks; D015992:Body Mass Index; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008099:Liver / Q000000981:diagnostic imaging* / Q000473:pathology; D008107:Liver Diseases / Q000000981:diagnostic imaging / Q000473:pathology; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D065626:Non-alcoholic Fatty Liver Disease / Q000000981:diagnostic imaging / Q000473:pathology; D010641:Phenotype; D011446:Prospective Studies; D012307:Risk Factors; D016896:Treatment Outcome; D006113:United Kingdom