title: Premorbid obesity, but not nutrition, prevents critical illness-induced muscle wasting and weakness.
abstract: BACKGROUND
  The 'obesity paradox' of critical illness refers to better survival with a higher body mass index. We hypothesized that fat mobilized from excess adipose tissue during critical illness provides energy more efficiently than exogenous macronutrients and could prevent lean tissue wasting.
  
  
  METHODS
  In lean and premorbidly obese mice, the effect of 5 days of sepsis-induced critical illness on body weight and composition, muscle wasting, and weakness was assessed, each with fasting and parenteral feeding. Also, in lean and overweight/obese prolonged critically ill patients, markers of muscle wasting and weakness were compared.
  
  
  RESULTS
  In mice, sepsis reduced body weight similarly in the lean and obese, but in the obese with more fat loss and less loss of muscle mass, better preservation of myofibre size and muscle force, and less loss of ectopic lipids, irrespective of administered feeding. These differences between lean and obese septic mice coincided with signs of more effective hepatic fatty acid and glycerol metabolism, and ketogenesis in the obese. Also in humans, better preservation of myofibre size and muscle strength was observed in overweight/obese compared with lean prolonged critically ill patients.
  
  
  CONCLUSIONS
  During critical illness premorbid obesity, but not nutrition, optimized utilization of stored lipids and attenuated muscle wasting and weakness.
authors.affiliation: Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, 3000, Leuven, Belgium.
authors.forename: Chloë
authors.initials: C
authors.lastname: Goossens
authors.affiliation: Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, 3000, Leuven, Belgium.
authors.forename: Mirna Bastos
authors.initials: MB
authors.lastname: Marques
authors.affiliation: Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, 3000, Leuven, Belgium.
authors.forename: Sarah
authors.initials: S
authors.lastname: Derde
authors.affiliation: Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, 3000, Leuven, Belgium.
authors.forename: Sarah
authors.initials: S
authors.lastname: Vander Perre
authors.affiliation: Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, 3000, Leuven, Belgium.
authors.forename: Thomas
authors.initials: T
authors.lastname: Dufour
authors.affiliation: Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, 3000, Leuven, Belgium.
authors.forename: Steven E
authors.initials: SE
authors.lastname: Thiessen
authors.affiliation: Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, 3000, Leuven, Belgium.
authors.forename: Fabian
authors.initials: F
authors.lastname: Güiza
authors.affiliation: Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, 3000, Leuven, Belgium.
authors.forename: Thomas
authors.initials: T
authors.lastname: Janssens
authors.affiliation: Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, 3000, Leuven, Belgium.
authors.forename: Greet
authors.initials: G
authors.lastname: Hermans
authors.affiliation: Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, 3000, Leuven, Belgium.
authors.forename: Ilse
authors.initials: I
authors.lastname: Vanhorebeek
authors.affiliation: Exercise Physiology Research Group, Department of Kinesiology, KU Leuven, 3000, Leuven, Belgium.
authors.forename: Katrien
authors.initials: K
authors.lastname: De Bock
authors.affiliation: Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, 3000, Leuven, Belgium.
authors.forename: Greet
authors.initials: G
authors.lastname: Van den Berghe
authors.affiliation: Clinical Division and Laboratory of Intensive Care Medicine, Department of Cellular and Molecular Medicine, KU Leuven, 3000, Leuven, Belgium.
authors.forename: Lies
authors.initials: L
authors.lastname: Langouche
mesh_terms: D020155:3-Hydroxybutyric Acid / Q000097:blood; D000368:Aged; D000818:Animals; D001823:Body Composition; D016638:Critical Illness; D005215:Fasting / Q000378:metabolism; D005227:Fatty Acids / Q000097:blood; D005260:Female; D005990:Glycerol / Q000097:blood; D006801:Humans; D008099:Liver / Q000378:metabolism; D008297:Male; D008810:Mice, Inbred C57BL; D008875:Middle Aged; D009124:Muscle Proteins / Q000235:genetics / Q000378:metabolism; D018908:Muscle Weakness / Q000378:metabolism / Q000473:pathology; D009133:Muscular Atrophy / Q000378:metabolism / Q000473:pathology; D009752:Nutritional Status; D050177:Overweight / Q000378:metabolism / Q000473:pathology; D010288:Parenteral Nutrition; D052097:Quadriceps Muscle / Q000033:anatomy & histology / Q000378:metabolism / Q000502:physiology; D017568:Rectus Abdominis / Q000033:anatomy & histology / Q000378:metabolism / Q000502:physiology; D018805:Sepsis / Q000378:metabolism / Q000473:pathology; D014280:Triglycerides / Q000378:metabolism
chemical_list: D005227:Fatty Acids; D009124:Muscle Proteins; D014280:Triglycerides; D005990:Glycerol; D020155:3-Hydroxybutyric Acid
keywords: Critical illness; Metabolism; Obesity; Skeletal muscle