title: Validation of a method to screen for pulmonary hypertension in advanced idiopathic pulmonary fibrosis.
abstract: BACKGROUND
  We have developed a method to screen for pulmonary hypertension (PH) in idiopathic pulmonary fibrosis (IPF) patients, based on a formula to predict mean pulmonary artery pressure (MPAP) from standard lung function measurements. The objective of this study was to validate this method in a separate group of IPF patients.
  
  
  METHODS
  Cross-sectional study of 60 IPF patients from two institutions. The accuracy of the MPAP estimation was assessed by examining the correlation between the predicted and measured MPAPs and the magnitude of the estimation error. The discriminatory ability of the method for PH was assessed using the area under the receiver operating characteristic curve (AUC).
  
  
  RESULTS
  There was strong correlation in the expected direction between the predicted and measured MPAPs (r = 0.72; p < 0.0001). The estimated MPAP was within 5 mm Hg of the measured MPAP 72% of the time. The AUC for predicting PH was 0.85, and did not differ by institution. A formula-predicted MPAP > 21 mm Hg was associated with a sensitivity, specificity, positive predictive value, and negative predictive value of 95%, 58%, 51%, and 96%, respectively, for PH defined as MPAP from right-heart catheterization > 25 mm Hg.
  
  
  CONCLUSIONS
  A prediction formula for MPAP using standard lung function measurements can be used to screen for PH in IPF patients.
authors.affiliation: Division of Pulmonary and Critical Care Medicine, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095, USA. dzisman@mednet.ucla.edu
authors.forename: David A
authors.initials: DA
authors.lastname: Zisman
authors.forename: Arun S
authors.initials: AS
authors.lastname: Karlamangla
authors.forename: Steven M
authors.initials: SM
authors.lastname: Kawut
authors.forename: Oksana A
authors.initials: OA
authors.lastname: Shlobin
authors.forename: Rajeev
authors.initials: R
authors.lastname: Saggar
authors.forename: David J
authors.initials: DJ
authors.lastname: Ross
authors.forename: Marvin I
authors.initials: MI
authors.lastname: Schwarz
authors.forename: John A
authors.initials: JA
authors.lastname: Belperio
authors.forename: Abbas
authors.initials: A
authors.lastname: Ardehali
authors.forename: Joseph P
authors.initials: JP
authors.lastname: Lynch
authors.forename: Steven D
authors.initials: SD
authors.lastname: Nathan
mesh_terms: D000368:Aged; D001795:Blood Pressure Determination / Q000379:methods*; D006328:Cardiac Catheterization; D003430:Cross-Sectional Studies; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D006976:Hypertension, Pulmonary / Q000175:diagnosis / Q000453:epidemiology*; D008297:Male; D008403:Mass Screening / Q000379:methods*; D008875:Middle Aged; D009017:Morbidity; D011237:Predictive Value of Tests; D011658:Pulmonary Fibrosis / Q000175:diagnosis / Q000453:epidemiology*; D012372:ROC Curve; D012189:Retrospective Studies; D014481:United States / Q000453:epidemiology