Protein turnover and metabolism in the elderly intensive care unit patient

Stuart M. Phillips, Roland N. Dickerson, Frederick A. Moore, Douglas Paddon-Jones, Peter J. M. Weijs

Research output: Contribution to journalArticleAcademicpeer-review

31 Citations (Scopus)


Many intensive care unit (ICU) patients do not achieve target protein intakes particularly in the early days following admittance. This period of iatrogenic protein undernutrition contributes to a rapid loss of lean, in particular muscle, mass in the ICU. The loss of muscle in older (aged >60 years) patients in the ICU may be particularly rapid due to a perfect storm of increased catabolic factors, including systemic inflammation, disuse, protein malnutrition, and reduced anabolic stimuli. This loss of muscle mass has marked consequences. It is likely that the older patient is already experiencing muscle loss due to sarcopenia; however, the period of stay in the ICU represents a greatly accelerated period of muscle loss. Thus, on discharge, the older ICU patient is now on a steeper downward trajectory of muscle loss, more likely to have ICU-acquired muscle weakness, and at risk of becoming sarcopenic and/or frail. One practice that has been shown to have benefit during ICU stays is early ambulation and physical therapy (PT), and it is likely that both are potent stimuli to induce a sensitivity of protein anabolism. Thus, recommendations for the older ICU patient would be provision of at least 1.2-1.5 g protein/kg usual body weight/d, regular and early utilization of ambulation (if possible) and/or PT, and follow-up rehabilitation for the older discharged ICU patient that includes rehabilitation, physical activity, and higher habitual dietary protein to change the trajectory of ICU-mediated muscle mass loss and weakness.

Original languageEnglish
Pages (from-to)112S-120S
JournalNutrition in clinical practice : official publication of the American Society for Parenteral and Enteral Nutrition
Issue number1_suppl
Early online date1 Feb 2017
Publication statusPublished - 1 Apr 2017


  • Aged
  • Body Weight
  • Critical Care
  • Dietary Proteins
  • Early Ambulation
  • Humans
  • Intensive Care Units
  • Journal Article
  • Muscle Weakness
  • Nutritional Requirements
  • Patient Discharge
  • Sarcopenia
  • anabolic resistance
  • intensive care unit
  • leucine
  • protein turnover
  • skeletal muscle

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