title: Comparative in-hospital morbidity and mortality after revision versus primary thoracic and lumbar spine fusion.
abstract: BACKGROUND
  Despite increasing utilization of surgical spine fusions, a paucity of literature addressing perioperative complications after revision posterior spinal fusion (RPSF) versus primary posterior spine fusion (PPSF) of the thoracic and lumbar spine exists.
  
  
  OBJECTIVE
  To examine demographics of patients undergoing PPSF and RPSF of the thoracic and lumbar spine, assess the incidence of perioperative morbidity and mortality, and determine independent risk factors for in-hospital death.
  
  
  METHODS
  Analysis of nationally representative data collected for the National Inpatient Sample (NIS).
  
  
  METHODS
  All discharges included in the NIS with a procedure code for posterior thoracic and lumbar spine fusion from 1998 to 2006.
  
  
  METHODS
  In-hospital mortality and morbidity.
  
  
  METHODS
  Data collected for each year between 1998 and 2006 for the NIS were analyzed. Discharges with a procedure code for thoracic and lumbar spine fusion were included in the sample. The prevalence of patient- as well as health care-related demographics was evaluated by procedure type (primary vs. revision). Frequencies of procedure-related complications and in-hospital mortality were analyzed. Independent predictors for in-hospital mortality were determined.
  
  
  RESULTS
  We identified 222,549 PPSF and 12,474 RPSF discharges between 1998 and 2006. Patients undergoing PPSF were significantly younger (51.23 years; confidence interval [CI]=51.16, 51.31) and had lower average comorbidity indices (0.40; CI=0.39, 0.41) than those undergoing RPSF (52.69 years; CI=52.43, 52.97) and (0.44; CI=0.43, 0.45), p<.0001. The incidence of procedure-related complications was 16.02% among RPSF compared with 13.44% in PPSF patients (p<.0001). In-hospital mortality rates after PPSF were approximately twice those of RPSF (0.28% vs. 0.15%, p=.006). Adjusted risk factors for increased in-hospital mortality included PPSF compared with RPSF, male gender, and increasing age. A number of comorbidities, complications, and specific surgical indications increased the risk for perioperative death.
  
  
  CONCLUSIONS
  Despite being performed in generally younger and healthier patients and having lower perioperative morbidity, PPSF procedures are associated with increased mortality compared with RPSF procedures. The findings of this study can be used for risk stratification, accurate patient consultation, and hypothesis formation for future research.
authors.affiliation: Department of Public Health, Hospital for Special Surgery, Weill Medical College of Cornell University, 535 East 70th St, New York, NY 10021, USA. may@hss.edu
authors.forename: Yan
authors.initials: Y
authors.lastname: Ma
authors.forename: Peter
authors.initials: P
authors.lastname: Passias
authors.forename: Licia K
authors.initials: LK
authors.lastname: Gaber-Baylis
authors.forename: Federico P
authors.initials: FP
authors.lastname: Girardi
authors.forename: Stavros G
authors.initials: SG
authors.lastname: Memtsoudis
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D008159:Lumbar Vertebrae; D008297:Male; D008875:Middle Aged; D009017:Morbidity; D011183:Postoperative Complications / Q000453:epidemiology*; D012086:Reoperation / Q000009:adverse effects / Q000401:mortality* / Q000706:statistics & numerical data; D013123:Spinal Fusion / Q000009:adverse effects / Q000401:mortality* / Q000706:statistics & numerical data; D013904:Thoracic Vertebrae