title: Clinical impact of lung age on postoperative complications in non-small cell lung cancer patients aged >70 y.
abstract: BACKGROUND
  Surgery for elderly patients with primary lung neoplasms has become relatively common as populations age; however, the high frequency of postoperative complications has prevented its broad application. Recently, the Japanese Respiratory Society proposed lung age (LA) as an index of lung function, but reports on the association between LA and the risk factors for postoperative complications with non-small cell lung cancer (NSCLC) surgery have been limited. In this study, we analyzed the clinical applicability of LA for elderly patients with NSCLC.
  
  
  METHODS
  We studied 320 patients aged >70 y underwent curative resections for NSCLC. LA was calculated based on the formula provided by the Japanese Respiratory Society, which depended on the patient's preoperative respiratory function and was divided into four age gap (AG) groups between the LA and the true age (TA). The categorical data were compared among the four groups.
  
  
  RESULTS
  The numbers of patients in groups A, B, C, and D were 80, 77, 79, and 84, respectively. For the univariate analysis, the preoperative factors for postoperative complications were gender, AG, and smoking (P < 0.05). In a multivariate analysis, AG proved to be an independent factor. Although we found no significant differences, there was a tendency for the prognosis to worsen with an increase in the AG (P = 0.06).
  
  
  CONCLUSIONS
  The AG was significantly associated with and an independent predictive factor for postoperative complications. We conclude that LA and AG are useful factors for predicting the risk of postoperative complications.
authors: Department of Thoracic Surgery, Kitasato University School of Medicine, Kanagawa, Japan. Electronic address: fumihiro@med.kitasato-u.ac.jp.
authors: Fumihiro
authors: F
authors: Ogawa
authors: Department of Cardiology, Tohoku University Graduate School of Medicine, Miyagi, Japan.
authors: Satoshi
authors: S
authors: Miyata
authors: Department of Thoracic Surgery, Kitasato University School of Medicine, Kanagawa, Japan.
authors: Hiroyasu
authors: H
authors: Nakashima
authors: Department of Thoracic Surgery, Kitasato University School of Medicine, Kanagawa, Japan.
authors: Yoshio
authors: Y
authors: Matsui
authors: Department of Thoracic Surgery, Kitasato University School of Medicine, Kanagawa, Japan.
authors: Kazu
authors: K
authors: Shiomi
authors: Department of Thoracic Surgery, Toho University School of Medicine, Tokyo, Japan.
authors: Akira
authors: A
authors: Iyoda
authors: Department of Thoracic Surgery, Kitasato University School of Medicine, Kanagawa, Japan.
authors: Yukitoshi
authors: Y
authors: Satoh
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D002289:Carcinoma, Non-Small-Cell Lung / Q000473:pathology / Q000601:surgery*; D005260:Female; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008168:Lung / Q000473:pathology* / Q000601:surgery; D008175:Lung Neoplasms / Q000473:pathology / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000401:mortality* / Q000473:pathology; D012189:Retrospective Studies; D016896:Treatment Outcome; D055815:Young Adult
keywords: Age gap; Lung age; Non–small cell lung cancer; Postoperative complications; Prognosis; Respiratory function; Surgical resection