title: Frailty and postoperative outcomes in patients undergoing surgery for degenerative spine disease.
abstract: Frailty is defined as a state of decreased reserve and susceptibility to stressors. The relationship between frailty and postoperative outcomes after degenerative spine surgery has not been studied.
  
  
  
  This study aimed to (1) determine prevalence of frailty in the degenerative spine population; (2) describe patient characteristics associated with frailty; and (3) determine the association between frailty and postoperative complications, mortality, length of stay, and discharge disposition.
  
  
  
  This is a retrospective analysis on a prospectively collected cohort from the National Surgical Quality Improvement Program (NSQIP).
  
  
  
  A total of 53,080 patients who underwent degenerative spine surgery between 2006 and 2012 were included in the study.
  
  
  
  A modified frailty index (mFI) with 11 variables derived from the NSQIP dataset was used to determine prevalence of frailty and its correlation with a composite outcome of perioperative complications as well as hospital length of stay, mortality, and discharge disposition.
  
  
  
  After calculating the mFI for each patient, the prevalence and predictors of frailty were determined for our cohort. The association of frailty with postoperative outcomes was determined after adjusting for known and suspected confounders using multivariate logistic regression.
  
  
  
  Frailty was present in 2,041 patients within the total population (4%) and in 8% of patients older than 65 years. Frailty severity increased with increasing age, male sex, African American race, higher body mass index, recent weight loss, paraplegia or quadriplegia, American Society of Anesthesiologists (ASA) score, and preadmission residence in a care facility. Frailty severity was an independent predictor of major complication (OR 1.15 for every 0.10 increase in mFI, 95%CI 1.09-1.21, p<.0005) and specifically predicted reoperation for postsurgical infection (OR 1.3, 95%CI 1.16-1.46, p<.0005). Prolonged length of stay and discharge to a new facility were also independently predicted by frailty severity (p<.0005). Frailty severity predicted 30-day mortality on unadjusted (OR 2.05, 95%CI 1.70-2.48, p<.0005) and adjusted analyses (OR 1.48, 95%CI 1.18-1.86, p<.0005).
  
  
  
  Frailty is an important predictor of postoperative outcomes following degenerative spine surgery. Preoperative recognition of frailty may be useful for perioperative optimization, risk stratification, and patient counseling.
authors.affiliation: Department of Anesthesiology, Pharmacology and Therapeutics, Vancouver General Hospital, University of British Columbia, Room 2449 JPP 899 West 12th Avenue, Vancouver, BC, Canada, V5Z 1M9. Electronic address: alana.flexman@vch.ca.
authors.forename: Alana M
authors.initials: AM
authors.lastname: Flexman
authors.affiliation: Department of Orthopedic Surgery, Centre Hospitalier Universitaire de Québec, 1401 18e rue, Local B-2408, Québec, QC, Canada, G1J 1Z4.
authors.forename: Raphaële
authors.initials: R
authors.lastname: Charest-Morin
authors.affiliation: Department of Anesthesiology, Pharmacology and Therapeutics, Vancouver General Hospital, University of British Columbia, Room 2449 JPP 899 West 12th Avenue, Vancouver, BC, Canada, V5Z 1M9.
authors.forename: Liam
authors.initials: L
authors.lastname: Stobart
authors.affiliation: Combined Neurosurgical and Orthopedic Spine Program, Department of Orthopedic Surgery, University of British Columbia, 818 West 10th Avenue, Vancouver, BC, Canada, V5Z 1M9.
authors.forename: John
authors.initials: J
authors.lastname: Street
authors.affiliation: Division of Respirology, Department of Medicine, St. Paul's Hospital, University of British Columbia, Ward 8B, 1081 Burrard Street, Vancouver, BC, Canada, V6Z 1Y6.
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Ryerson
mesh_terms: D000368:Aged; D005260:Female; D016330:Frail Elderly; D006801:Humans; D055959:Intervertebral Disc Degeneration / Q000453:epidemiology / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D019635:Neurosurgical Procedures / Q000009:adverse effects*; D011183:Postoperative Complications / Q000453:epidemiology*; D012086:Reoperation / Q000706:statistics & numerical data
keywords: Degenerative spine disease; Frailty; Morbidity; Outcomes; Risk stratification; Spine surgery