title: Insulin Resistance Increases MRI-Estimated Pancreatic Fat in Nonalcoholic Fatty Liver Disease and Normal Controls.
abstract: Background. Ectopic fat deposition in the pancreas and its relationship with hepatic steatosis and insulin resistance have not been compared between patients with nonalcoholic fatty liver disease (NAFLD) and healthy controls. Aim. Using a novel magnetic resonance imaging (MRI) based biomarker, the proton-density-fat-fraction (MRI-PDFF), we compared pancreatic fat content in patients with biopsy-proven NAFLD to healthy controls and determined whether it is associated with insulin resistance and liver fat content. Methods. This nested case-control study was derived from two prospective studies including 43 patients with biopsy-proven NAFLD and 49 healthy controls who underwent biochemical testing and MRI. Results. Compared to healthy controls, patients with NAFLD had significantly higher pancreatic MRI-PDFF (3.6% versus 8.5%, P value <0.001), and these results remained consistent in multivariable-adjusted models including age, sex, body mass index, and diabetes (P value =0.03). We found a strong correlation between hepatic and pancreatic MRI-PDFF (Spearman correlation, P = 0.57, P value <0.001). Participants with increased insulin resistance determined by homeostatic-model-of-insulin-resistance (HOMA-IR) greater than 2.5 had higher pancreatic (7.3% versus 4.5%, P value =0.015) and liver (13.5% versus 4.0%, P value <0.001) MRI-PDFF. Conclusion. Patients with NAFLD have greater pancreatic fat than normal controls. Insulin resistance is associated with liver and pancreatic fat accumulation.
authors.affiliation: Division of Internal Medicine, Department of Medicine, University of California at San Diego, UC San Diego Health System, 9500 Gilman Drive, MC 0063, La Jolla, CA 92093, USA.
authors.forename: Niraj S
authors.initials: NS
authors.lastname: Patel
authors.affiliation: Department of Pathology, University of California at San Diego, UC San Diego Health System, 9500 Gilman Drive, MC 0063, La Jolla, CA 92093, USA.
authors.forename: Michael R
authors.initials: MR
authors.lastname: Peterson
authors.affiliation: Department of Pathology, University of California at San Diego, UC San Diego Health System, 9500 Gilman Drive, MC 0063, La Jolla, CA 92093, USA.
authors.forename: Grace Y
authors.initials: GY
authors.lastname: Lin
authors.affiliation: Division of Gastroenterology, Department of Pediatrics, University of California at San Diego, UC San Diego Health System, 9500 Gilman Drive, MC 0063, La Jolla, CA 92093, USA.
authors.forename: Ariel
authors.initials: A
authors.lastname: Feldstein
authors.affiliation: Division of Gastroenterology, Department of Medicine, University of California at San Diego, UC San Diego Health System, 9500 Gilman Drive, MC 0063, La Jolla, CA 92093, USA.
authors.forename: Bernd
authors.initials: B
authors.lastname: Schnabl
authors.affiliation: Division of Epidemiology, Department of Family and Preventive Medicine, University of California at San Diego, UC San Diego Health System, 9500 Gilman Drive, MC 0063, La Jolla, CA 92093, USA.
authors.forename: Ricki
authors.initials: R
authors.lastname: Bettencourt
authors.affiliation: Division of Gastroenterology, Department of Medicine, University of California at San Diego, UC San Diego Health System, 9500 Gilman Drive, MC 0063, La Jolla, CA 92093, USA.
authors.forename: Ekihiro
authors.initials: E
authors.lastname: Seki
authors.affiliation: Liver Imaging Group, Department of Radiology, University of California at San Diego, UC San Diego Health System, 9500 Gilman Drive, MC 0063, La Jolla, CA 92093, USA.
authors.forename: Claude B
authors.initials: CB
authors.lastname: Sirlin
authors.affiliation: Division of Gastroenterology, Department of Medicine, University of California at San Diego, UC San Diego Health System, 9500 Gilman Drive, MC 0063, La Jolla, CA 92093, USA ; Division of Epidemiology, Department of Family and Preventive Medicine, University of California at San Diego, UC San Diego Health System, 9500 Gilman Drive, MC 0063, La Jolla, CA 92093, USA.
authors.forename: Rohit
authors.initials: R
authors.lastname: Loomba