title: Walking distance on 6-MWT is a prognostic factor in idiopathic pulmonary fibrosis.
abstract: OBJECTIVE
  Idiopathic pulmonary fibrosis (IPF) is a progressive disease with high mortality rates and a median survival of 2-3 years from time of diagnosis. The prognosis for any individual patient, however, is variable. To elucidate the clinical significance of 6-min walking test (6-MWT) in patients with IPF, we sought to assess the relationship between distance walked and desaturation during this test and pulmonary function tests (PFTs). We also evaluate the prognostic value of 6-MWT in comparison with PFTs at baseline and during follow-up.
  
  
  METHODS
  The clinical data of 44 patients with IPF were retrospectively analysed. Twenty-nine patients had an additional evaluation after 12 month of follow-up.
  
  
  RESULTS
  Distance walked in 6 min was independently related to mortality by multivariate analysis. Patients walking less then 212 m had a significantly lower survival than those walking farther, assessed by Kaplan-Meier survival curves (log-rank test, p<0.036). During a mean follow-up period of 19.8 months (range 3.2-46.4), 11 patients died of causes related to disease. Changes in meters walked at 12 months evaluation were also predictive of survival (p=0.05).
  
  
  CONCLUSIONS
  These results confirm that in IPF distance walked in 6 min is independent associated with mortality.
authors.affiliation: Unità Operativa di Pneumologia e Terapia Semi-Intensiva Respiratoria - Servizio di Fisiopatologia Respiratoria ed Emodinamica Polmonare Ospedale San Giuseppe Fatebenefratelli, Via San Vittore 12, 20123 Milan, Italy.
authors.forename: Antonella
authors.initials: A
authors.lastname: Caminati
authors.forename: Achille
authors.initials: A
authors.lastname: Bianchi
authors.forename: Roberto
authors.initials: R
authors.lastname: Cassandro
authors.forename: Maria Rosa
authors.initials: MR
authors.lastname: Mirenda
authors.forename: Sergio
authors.initials: S
authors.lastname: Harari
mesh_terms: D019540:Area Under Curve; D005080:Exercise Test / Q000379:methods; D017079:Exercise Tolerance; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D054990:Idiopathic Pulmonary Fibrosis / Q000401:mortality / Q000503:physiopathology*; D053208:Kaplan-Meier Estimate; D008168:Lung / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D015996:Survival Rate; D013997:Time Factors; D014797:Vital Capacity; D016138:Walking