title: Sarcopenia, obesity and sarcopenic obesity: effects on liver function and volume in patients scheduled for major liver resection.
abstract: BACKGROUND
  Sarcopenia, obesity and sarcopenic obesity have been linked to impaired outcome after liver surgery. Preoperative liver function of sarcopenic, obese and sarcopenic-obese patients might be reduced, possibly leading to more post-operative morbidity. The aim of this study was to explore whether liver function and volume were influenced by body composition in patients undergoing liver resection.
  
  
  METHODS
  In 2011 and 2012, all consecutive patients undergoing the methacetin breath liver function test were included. Liver volumetry and muscle mass analysis were performed using preoperative CT scans and Osirix(®) software. Muscle mass and body-fat% were calculated. Predefined cut-off values for sarcopenia and the top two body-fat% quintiles were used to identify sarcopenia and obesity, respectively. Histologic assessment of the resected liver gave insight in background liver disease.
  
  
  RESULTS
  A total number of 80 patients were included. Liver function and volume were comparable in sarcopenic(-obese) and non-sarcopenic(-obese) patients. Obese patients showed significantly reduced liver function [295 (95-508) vs. 358 (96-684) µg/kg/h, P = 0.018] and a trend towards larger liver size [1694 (1116-2685) vs. 1533 (869-2852) mL, P = 0.079] compared with non-obese patients. Weight (r = -0.40), body surface area (r = -0.32), estimated body-fat% (r = -0.43) and body mass index (r = -0.47) showed a weak but significant negative (all P < 0.05) correlation with liver function. Moreover, body-fat% was identified as an independent factor negatively affecting the liver function.
  
  
  CONCLUSIONS
  Sarcopenia and sarcopenic obesity did not seem to influence liver size and function negatively. However, obese patients had larger, although less functional, livers, indicating dissociation of liver function and volume in these patients.
authors.affiliation: Department of Surgery, Division of General, Visceral and Transplantation Surgery, RWTH Aachen University, Aachen, Germany.|Department of Surgery, Maastricht University Medical Centre & Nutrim School for Nutrition, Toxicology and Metabolism, Maastricht University, Maastricht, The Netherlands.|Euregional HPB collaboration Aachen-Maastricht, Aachen-Maastricht, Germany-The Netherlands.
authors.forename: Toine M
authors.initials: TM
authors.lastname: Lodewick
authors.affiliation: Department of Surgery, Division of General, Visceral and Transplantation Surgery, RWTH Aachen University, Aachen, Germany.|Euregional HPB collaboration Aachen-Maastricht, Aachen-Maastricht, Germany-The Netherlands.
authors.forename: Anjali A J
authors.initials: AA
authors.lastname: Roeth
authors.affiliation: Department of Surgery, Maastricht University Medical Centre & Nutrim School for Nutrition, Toxicology and Metabolism, Maastricht University, Maastricht, The Netherlands.|Euregional HPB collaboration Aachen-Maastricht, Aachen-Maastricht, Germany-The Netherlands.|Department of Surgery, Division of Surgery and Interventional Science, Royal Free Hospital, and University College London, London, United Kingdom.
authors.forename: Steven W M
authors.initials: SW
authors.lastname: Olde Damink
authors.affiliation: Department of Surgery, Division of General, Visceral and Transplantation Surgery, RWTH Aachen University, Aachen, Germany.|Euregional HPB collaboration Aachen-Maastricht, Aachen-Maastricht, Germany-The Netherlands.
authors.forename: Patrick H
authors.initials: PH
authors.lastname: Alizai
authors.affiliation: Department of Surgery, Maastricht University Medical Centre & Nutrim School for Nutrition, Toxicology and Metabolism, Maastricht University, Maastricht, The Netherlands.|Euregional HPB collaboration Aachen-Maastricht, Aachen-Maastricht, Germany-The Netherlands.
authors.forename: Ronald M
authors.initials: RM
authors.lastname: van Dam
authors.affiliation: Institute of Pathology, RWTH Aachen University, Aachen, Germany.
authors.forename: Nikolaus
authors.initials: N
authors.lastname: Gassler
authors.affiliation: Department of Surgery, Division of General, Visceral and Transplantation Surgery, RWTH Aachen University, Aachen, Germany.|Euregional HPB collaboration Aachen-Maastricht, Aachen-Maastricht, Germany-The Netherlands.
authors.forename: Mark
authors.initials: M
authors.lastname: Schneider
authors.affiliation: Department of Surgery, Maastricht University Medical Centre & Nutrim School for Nutrition, Toxicology and Metabolism, Maastricht University, Maastricht, The Netherlands.
authors.forename: Simon A W G
authors.initials: SA
authors.lastname: Dello
authors.affiliation: Department of Surgery, Division of General, Visceral and Transplantation Surgery, RWTH Aachen University, Aachen, Germany.|Euregional HPB collaboration Aachen-Maastricht, Aachen-Maastricht, Germany-The Netherlands.
authors.forename: Maximilian
authors.initials: M
authors.lastname: Schmeding
authors.affiliation: Department of Surgery, Maastricht University Medical Centre & Nutrim School for Nutrition, Toxicology and Metabolism, Maastricht University, Maastricht, The Netherlands.|Euregional HPB collaboration Aachen-Maastricht, Aachen-Maastricht, Germany-The Netherlands.
authors.forename: Cornelis H C
authors.initials: CH
authors.lastname: Dejong
authors.affiliation: Department of Surgery, Division of General, Visceral and Transplantation Surgery, RWTH Aachen University, Aachen, Germany.|Euregional HPB collaboration Aachen-Maastricht, Aachen-Maastricht, Germany-The Netherlands.
authors.forename: Ulf P
authors.initials: UP
authors.lastname: Neumann
keywords: Body fat percentage; L3 skeletal muscle index; LiMAx; Liver function; Obesity; Sarcopenia; Volumetry