title: 'Lung age' predicts post-operative complications and survival in lung cancer patients.
abstract: OBJECTIVE
  The Japanese Respiratory Society recently proposed 'lung age' as an easily understood concept of respiratory function. In this study, we evaluated whether 'lung age' could be a useful predictor of post-operative respiratory complications and survival patients with lung cancer treated surgically.
  
  
  METHODS
  The study recruited 308 patients who underwent surgery for primary non-small-cell lung cancer. All patients had preoperative pulmonary function testing. 'Lung age' was determined using the methods advocated by the Japanese Respiratory Society. Based on the difference between 'real age' (R) and 'lung age' (L), patients were classified into five groups: group A: R-L > 15 (n = 37), B: 5 < R-L <or= 15 (n = 50), C: -5 <or= R-L <or= 5 (n = 73), D: -15 <or= R-L < -5 (n = 54), E: -15 > R-L (n = 94). Clinicopathological factors, post-operative respiratory complications and survival were compared between the groups.
  
  
  RESULTS
  Gender, smoking status and index, histology, operative approach and FEV(1) were significantly associated with the group classification. The incidence of complications was significantly higher in group E compared with other groups (P = 0.003). Multivariate analysis showed that the group classification by 'lung age' was an independent predictor of post-operative respiratory complications (P = 0.02). Overall survival differed significantly between the groups (P = 0.03).
  
  
  CONCLUSIONS
  'Lung age' could be useful for the prediction of post-operative respiratory complications and survival in patients with lung cancer treated surgically.
authors.affiliation: Department of General Thoracic Surgery, Tottori University Hospital, Yonago, Tottori, Japan. tharuki@med.tottori-u.ac.jp
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Haruki
authors.forename: Hiroshige
authors.initials: H
authors.lastname: Nakamura
authors.forename: Yuji
authors.initials: Y
authors.lastname: Taniguchi
authors.forename: Ken
authors.initials: K
authors.lastname: Miwa
authors.forename: Yoshin
authors.initials: Y
authors.lastname: Adachi
authors.forename: Shinji
authors.initials: S
authors.lastname: Fujioka
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000473:pathology* / Q000502:physiology; D002289:Carcinoma, Non-Small-Cell Lung / Q000401:mortality* / Q000473:pathology / Q000601:surgery*; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D015994:Incidence; D007564:Japan; D008168:Lung / Q000473:pathology* / Q000503:physiopathology; D008175:Lung Neoplasms / Q000401:mortality* / Q000473:pathology / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011183:Postoperative Complications / Q000453:epidemiology*; D011237:Predictive Value of Tests; D011379:Prognosis; D012189:Retrospective Studies; D015996:Survival Rate