title: Cost Variation of Anterior Cervical Fusions in Elderly Medicare Beneficiaries.
abstract: METHODS
  Retrospective database review.
  
  
  OBJECTIVE
  To determine how demographics and comorbid diagnoses influence hospital costs during admission for anterior cervical fusions (ACFs) in the elderly Medicare population.
  
  
  BACKGROUND
  Elective ACFs to treat degenerative cervical pathology are extremely common within the elderly population. Although it is well known that every patient has a significantly different medical profile that guides treatment and postoperative care, little information is available regarding how hospital costs vary from patient to patient.
  
  
  METHODS
  Medicare records from the PearlDiver database (2011-2012) were retrospectively queried to select all 65- to 84-year-old patients who underwent primary, 1 to 2 level ACF (International Classification of Diseases, Ninth Revision, Clinical Modification: 81.02) for either cervical spondylosis or cervical disc disease. All patients with corpectomies, posterior cervical fusions, and all other same-day spine fusion surgeries were excluded. The primary outcome of this study was Medicare reimbursement from the full inpatient stay as associated with the selected International Classification of Diseases, Ninth Revision procedure code. The relative contributions of year, age, sex, region, myelopathy diagnosis, and various comorbidities to the total cost were determined with both univariate statistics and multivariate analysis. For all analyses, P < 0.001 was determined to be significant.
  
  
  RESULTS
  In total, 21,853 patients were selected for analysis. The average reimbursement for the full cohort was $13,648 ± $7306. On multivariate analysis, advanced age ($1083), diagnosis of myelopathy ($2150), diabetes mellitus ($1019), obesity ($651), congestive heart failure ($1523), chronic kidney disease ($1962), and chronic pulmonary disease ($489) were all factors that increased costs. Of note, sex, smoking history, and prior liver disease were not associated with changes in cost.
  
  
  CONCLUSIONS
  Medicare reimbursements provide a value means by which determinants of cost can be elucidated. Although multiple comorbidities, older age, and myelopathy diagnosis could be theorized to contribute to increased costs, there is still some uncertainty regarding their relative costs. These data are informative to practicing physicians as health care as a whole transitions to a more value-based approach.
  
  
  METHODS
  4.
authors.affiliation: Department of Orthopedic Surgery, Johns Hopkins Hospital, Baltimore, MD.
authors.forename: Varun
authors.initials: V
authors.lastname: Puvanesarajah
authors.affiliation: Department of Orthopedic Surgery, Johns Hopkins Hospital, Baltimore, MD.
authors.forename: David J
authors.initials: DJ
authors.lastname: Kirby
authors.affiliation: Department of Orthopedic Surgery, Johns Hopkins Hospital, Baltimore, MD.
authors.forename: Amit
authors.initials: A
authors.lastname: Jain
authors.affiliation: Department of Orthopedic Surgery, University of Virginia, Charlottesville, VA.
authors.forename: Brian C
authors.initials: BC
authors.lastname: Werner
authors.affiliation: Department of Orthopedic Surgery, University of Virginia, Charlottesville, VA.
authors.forename: Hamid
authors.initials: H
authors.lastname: Hassanzadeh
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002574:Cervical Vertebrae / Q000601:surgery*; D017721:Hospital Costs / Q000706:statistics & numerical data*; D006801:Humans; D006278:Medicare; D012189:Retrospective Studies; D013123:Spinal Fusion / Q000191:economics*; D014481:United States / Q000453:epidemiology