title: Outcomes and Costs for Major Lung Resection in the United States: Which Patients Benefit Most From High-Volume Referral?
abstract: BACKGROUND
  Accountable care organizations are designed to improve value by decreasing costs and maintaining quality. Strategies to maximize value are needed for high-risk surgery. We wanted to understand whether certain patient groups were differentially associated with better outcomes at high-volume hospitals in terms of quality and cost.
  
  
  METHODS
  In all, 37,746 patients underwent elective major lung resection in 1,273 hospitals in the Nationwide Inpatient Sample from 2007 to 2011. Patients were stratified by hospital volume quartile and substratified by preoperative mortality risk, age, and chronic obstructive pulmonary disease status. Mortality was evaluated using clustered multivariable hierarchical logistic regression controlling for patient comorbidity, demographics, and procedure. Adjusted cost was evaluated using generalized linear models fit to a gamma distribution.
  
  
  RESULTS
  Patients were grouped into volume quartiles based on cases per year (less than 21, 21 to 40, 40 to 78, and more than 78). Patient characteristics and procedure mix differed across quartiles. Overall, mortality decreased across volume quartiles (lowest 1.9% versus highest 1.1%, p < 0.0001). Patients aged more than 80 years were associated with greater absolute and relative mortality rates than patients less than 60 years old in highest volume versus lowest volume hospitals (age more than 80 years, 4.2% versus 1.3%, p < 0.0001, odds ratio 3.31, 95% confidence interval: 1.89 to 5.80; age less than 60 years, 1.0% versus 0.8%, p = 0.19, odds ratio 1.38, 95% confidence interval: 0.74 to 2.56). Patients with high preoperative risk (more than 75th percentile) were also associated with lower absolute mortality in high-volume hospitals. Adjusted costs were not significantly different across quartiles or patient strata.
  
  
  CONCLUSIONS
  Older patients show a significantly stronger volume-outcome relationship than patients less than 60 years of age. Costs were equivalent across volume quartile and patient strata. Selective patient referral may be a strategy to improve outcomes for elderly patients undergoing lung resection.
authors.affiliation: Center for Surgery and Public Health, Department of Surgery, Brigham and Women's Hospital, Boston, Massachusetts; Division of General Surgery, Department of Surgery, University of Toronto, Toronto, Ontario, Canada; Division of Thoracic Surgery, Department of Surgery, University of Toronto, Toronto, Ontario, Canada. Electronic address: elliot.wakeam@utoronto.ca.
authors.forename: Elliot
authors.initials: E
authors.lastname: Wakeam
authors.affiliation: Center for Surgery and Public Health, Department of Surgery, Brigham and Women's Hospital, Boston, Massachusetts; Department of Anesthesiology, Mayo Clinic, Rochester, Minnesota.
authors.forename: Joseph A
authors.initials: JA
authors.lastname: Hyder
authors.affiliation: Center for Surgery and Public Health, Department of Surgery, Brigham and Women's Hospital, Boston, Massachusetts.
authors.forename: Stuart R
authors.initials: SR
authors.lastname: Lipsitz
authors.affiliation: Division of Thoracic Surgery, Department of Surgery, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Gail E
authors.initials: GE
authors.lastname: Darling
authors.affiliation: Center for Surgery and Public Health, Department of Surgery, Brigham and Women's Hospital, Boston, Massachusetts; Department of Surgery, University of Utah School of Medicine, Salt Lake City, Utah.
authors.forename: Samuel R G
authors.initials: SR
authors.lastname: Finlayson
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003365:Costs and Cost Analysis; D005260:Female; D061847:Hospitals, High-Volume; D061846:Hospitals, Low-Volume; D006801:Humans; D008297:Male; D008875:Middle Aged; D063868:Patient Outcome Assessment; D011013:Pneumonectomy / Q000191:economics* / Q000379:methods; D012017:Referral and Consultation / Q000706:statistics & numerical data; D012189:Retrospective Studies; D016896:Treatment Outcome; D014481:United States