title: Obesity and underweight are associated with an increased risk of death after lung transplantation.
abstract: BACKGROUND
  Obesity is considered a relative contraindication to lung transplantation, based on studies that have not accounted for key confounders. Little is known about the risk of death for underweight candidates after transplantation.
  
  
  OBJECTIVE
  To examine the associations of pretransplant obesity and underweight with the risk of death after lung transplantation.
  
  
  METHODS
  We examined 5,978 adults with cystic fibrosis, chronic obstructive pulmonary disease, and diffuse parenchymal lung disease who underwent lung transplantation in the United States between 1995 and 2003. We used Cox models and generalized additive models to examine the association between pretransplant body mass index and the risk of death after lung transplantation with adjustment for donor and recipient factors.
  
  
  RESULTS
  The median follow-up time was 4.2 years. Compared with normal weight recipients, the multivariable-adjusted rates of death were 15% higher for underweight recipients (95% confidence interval, 3 to 28%), 15% higher for overweight recipients (95% confidence interval, 6 to 26%), and 22% higher for obese recipients (95% confidence interval, 8 to 39%). These relationships persisted when stratified by diagnosis. The multivariable-adjusted population attributable fraction was 12% at 1 year and 8% at 5 years.
  
  
  CONCLUSIONS
  Both obesity and underweight are independent risk factors for death after lung transplantation, contributing to up to 12% of deaths in the first year after transplantation. Primary care providers and pulmonologists should promote a healthy weight for patients with lung disease long before transplantation is considered.
authors.affiliation: Department of Medicine, College of Physicians and Surgeons, Columbia University, New York, New York 10032, USA. DL427@columbia.edu
authors.forename: David J
authors.initials: DJ
authors.lastname: Lederer
authors.forename: Jessie S
authors.initials: JS
authors.lastname: Wilt
authors.forename: Frank
authors.initials: F
authors.lastname: D'Ovidio
authors.forename: Matthew D
authors.initials: MD
authors.lastname: Bacchetta
authors.forename: Lori
authors.initials: L
authors.lastname: Shah
authors.forename: Shankari
authors.initials: S
authors.lastname: Ravichandran
authors.forename: Jenny
authors.initials: J
authors.lastname: Lenoir
authors.forename: Brenda
authors.initials: B
authors.lastname: Klein
authors.forename: Joshua R
authors.initials: JR
authors.lastname: Sonett
authors.forename: Selim M
authors.initials: SM
authors.lastname: Arcasoy
mesh_terms: D000328:Adult; D015992:Body Mass Index; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006084:Graft Rejection / Q000150:complications; D006801:Humans; D008171:Lung Diseases / Q000150:complications* / Q000401:mortality / Q000601:surgery; D016040:Lung Transplantation / Q000401:mortality*; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000150:complications* / Q000401:mortality; D016017:Odds Ratio; D012131:Respiratory Insufficiency / Q000150:complications; D012189:Retrospective Studies; D012307:Risk Factors; D016019:Survival Analysis; D013851:Thinness / Q000150:complications* / Q000401:mortality; D014481:United States