title: A retrospective study of prognostic factors in patients with interstitial pneumonia receiving long-term oxygen therapy.
abstract: OBJECTIVE
  We retrospectively analyzed patients with clinically diagnosed interstitial pneumonia to investigate the factors which contribute to the difference in prognosis from the initiation of long-term oxygen therapy (LTOT) among subtypes.
  
  
  METHODS
  Seventy-six patients with clinically diagnosed idiopathic interstitial pneumonia (IIP; n = 49) or interstitial pneumonia associated with collagen vascular disease (CVD-IP; n = 27) in whom LTOT was initiated in our facility from January 1999 to December 2012 were analyzed.
  
  
  RESULTS
  Patients with CVD-IP had significantly longer survival time from the initiation of LTOT than those with IIP with the median survival of 51.7 months versus 18.8 months, respectively. The 1-year survival rate was 92.4% for patients with CVD-IP versus 76.5% for those with IIP, and 2-year survival was 88.6 versus 36.0%, respectively. The patterns classified with high-resolution computed tomography (HRCT) were not associated with prognosis. The association between pulmonary hypertension and prognosis was unclear. In results of the multivariate Cox analysis which included factors demonstrating p < 0.1 in the univariate Cox analysis, male gender, low body mass index, and the absence of collagen vascular disease (CVD) were significantly associated with poor prognosis.
  
  
  CONCLUSIONS
  After the initiation of LTOT, patients with IIP had poor prognosis regardless of the patterns classified with HRCT, while those with CVD-IP survived longer. Male gender, low body mass index, and the absence of CVD were the independent negative prognostic factors in patients with interstitial pneumonia receiving LTOT.
authors: Department of Respiratory Medicine, Allergy and Rheumatic Diseases, Osaka University Graduate School of Medicine, 2-2 Yamadaoka Suita, Osaka, 565-0871, Japan.
authors: Masayoshi
authors: M
authors: Higashiguchi
authors: Takashi
authors: T
authors: Kijima
authors: Hiromitsu
authors: H
authors: Sumikawa
authors: Osamu
authors: O
authors: Honda
authors: Toshiyuki
authors: T
authors: Minami
authors: Haruhiko
authors: H
authors: Hirata
authors: Koji
authors: K
authors: Inoue
authors: Izumi
authors: I
authors: Nagatomo
authors: Yoshito
authors: Y
authors: Takeda
authors: Hiroshi
authors: H
authors: Kida
authors: Noriyuki
authors: N
authors: Tomiyama
authors: Atsushi
authors: A
authors: Kumanogoh
mesh_terms: D000368:Aged; D015992:Body Mass Index; D003095:Collagen Diseases / Q000175:diagnosis / Q000401:mortality / Q000503:physiopathology / Q000628:therapy*; D005260:Female; D006801:Humans; D007564:Japan; D053208:Kaplan-Meier Estimate; D008168:Lung / Q000503:physiopathology; D017563:Lung Diseases, Interstitial / Q000175:diagnosis / Q000401:mortality / Q000503:physiopathology / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D010102:Oxygen Inhalation Therapy / Q000009:adverse effects / Q000401:mortality; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D012307:Risk Factors; D012737:Sex Factors; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome; D014652:Vascular Diseases / Q000175:diagnosis / Q000401:mortality / Q000503:physiopathology / Q000628:therapy*