title: Cardiorespiratory fitness predicts mortality and hospital length of stay after major elective surgery in older people.
abstract: OBJECTIVE
  This study aimed to define the relationship between cardiorespiratory fitness and age in the context of postsurgery mortality and morbidity in older people.
  
  
  BACKGROUND
  Postsurgery mortality and morbidity increase with age. Cardiorespiratory fitness also declines with age, and the independent and linked associations between cardiorespiratory fitness and age on postsurgical mortality and morbidity remain to be determined.
  
  
  METHODS
  An unselected consecutive group of 389 adults with a mean age of 66 years (range 26-86 years) underwent cardiorespiratory exercise testing before major hepatobiliary surgery at a single center. Mortality and critical care unit and hospital lengths of stay were collected from patient records. Primary outcomes were in-hospital all-cause mortality after surgery and hospital and critical care lengths of stay.
  
  
  RESULTS
  Anaerobic threshold was the most significant independent predictor for postoperative mortality (P = 0.003; β = -0.657 and odds ratio = 0.52) in 18 of 389 (4.6%) patients who died during their in-hospital stay. Age was not a significant predictor in this model. Older people with normal cardiorespiratory fitness spent the same number of days in the hospital or critical care unit as younger people with similar cardiorespiratory fitness (13 vs 12; P = 0.08 and 1 vs 1; P = 0.103). Patients older than 75 years with low cardiorespiratory fitness spent a median of 11 days longer in hospital (23 vs 12; P < 0.0001) and 2 days longer in critical care (2.9 vs 0.9; P < 0.0001) when compared with patients with adequate cardiorespiratory fitness.
  
  
  CONCLUSIONS
  Cardiorespiratory fitness is an independent predictor of mortality and length of hospital stay and provides significantly more accurate prognostic information than age alone. Clinicians should consider both the prognostic value of cardiorespiratory testing and techniques to preserve cardiorespiratory function before elective surgery in older people.
authors.affiliation: Institute of Cellular Medicine, Newcastle University; Newcastle upon Tyne, United Kingdom.
authors.forename: Chris P
authors.initials: CP
authors.lastname: Snowden
authors.forename: James
authors.initials: J
authors.lastname: Prentis
authors.forename: Byron
authors.initials: B
authors.lastname: Jacques
authors.forename: Helen
authors.initials: H
authors.lastname: Anderson
authors.forename: Derek
authors.initials: D
authors.lastname: Manas
authors.forename: Dave
authors.initials: D
authors.lastname: Jones
authors.forename: Michael
authors.initials: M
authors.lastname: Trenell
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D015308:Anaerobic Threshold; D016009:Chi-Square Distribution; D017558:Elective Surgical Procedures; D005080:Exercise Test; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D007902:Length of Stay / Q000706:statistics & numerical data*; D008297:Male; D008875:Middle Aged; D010809:Physical Fitness; D011237:Predictive Value of Tests; D012372:ROC Curve; D012044:Regression Analysis