title: Idiopathic pulmonary fibrosis and emphysema: decreased survival associated with severe pulmonary arterial hypertension.
abstract: BACKGROUND
  It has been suggested that the presence of emphysema modifies the outcome of patients with idiopathic pulmonary fibrosis (IPF). In this article we compare clinical features, smoking history, pulmonary function, estimated systolic pulmonary artery pressure (eSPAP), and mortality in IPF with emphysema vs IPF without emphysematous changes.
  
  
  METHODS
  A cohort of 110 IPF patients was evaluated. Clinical data were collected from clinical charts. High-resolution CT (HRCT) scans were examined by an expert blinded to clinical data, and patients were classified into the following two groups: patients with IPF with emphysema; and patients with IPF without emphysema. The Kaplan-Meier method, log-rank test, and Cox regression model were used for statistical analyses.
  
  
  RESULTS
  The prevalence of emphysema in the IPF cohort was 28% (31 of 110 patients). IPF with emphysema was significantly associated with male gender (odds ratio [OR], 18; 95% confidence interval [CI], 2.7 to 773.7; p = 0.0003), and smoking (OR, 3.8; 95% CI, 1.36 to 11.6; p = 0.004). Patients with IPF and emphysema had a higher mean (+/- SD) decrease in oxygen saturation during rest and exercise (16.3 +/- 6.7% vs 13.5 +/- 4.6%, respectively; p = 0.04), a higher mean fibrosis HRCT scan score (1.75 +/- 0.36 vs 1.55 +/- 0.38, respectively; p = 0.015), a higher eSPAP (82 +/- 20 vs 57 +/- 15 mm Hg, respectively; p < 0.0001), and lower median survival time (25 vs 34 months, respectively; p = 0.01) than patients with IPF without emphysema. The Cox regression model showed that the two most important variables associated with mortality were FVC < 50% predicted (hazard ratio [HR], 2.6; 95% CI, 1.19 to 5.68; p = 0.016) and eSPAP >or= 75 mm Hg (HR, 2.25; 95% CI, 1.12 to 4.54; p = 0.022).
  
  
  CONCLUSIONS
  IPF patients with emphysema exhibited higher mortality compared with those with IPF without emphysema. This dire prognosis seems to be at least partially associated with the development of severe pulmonary arterial hypertension.
authors.affiliation: Instituto Nacional de Enfermedades Respiratorias, Mexico City, Mexico.
authors.forename: Mayra
authors.initials: M
authors.lastname: Mejía
authors.affiliation: Instituto Nacional de Enfermedades Respiratorias, Mexico City, Mexico.
authors.forename: Guillermo
authors.initials: G
authors.lastname: Carrillo
authors.affiliation: Instituto Nacional de Enfermedades Respiratorias, Mexico City, Mexico; Universidad Nacional Autónoma de México, Mexico City, Mexico.
authors.forename: Jorge
authors.initials: J
authors.lastname: Rojas-Serrano
authors.affiliation: Instituto Nacional de Enfermedades Respiratorias, Mexico City, Mexico.
authors.forename: Andrea
authors.initials: A
authors.lastname: Estrada
authors.affiliation: Instituto Nacional de Enfermedades Respiratorias, Mexico City, Mexico.
authors.forename: Teresa
authors.initials: T
authors.lastname: Suárez
authors.affiliation: Instituto Nacional de Enfermedades Respiratorias, Mexico City, Mexico.
authors.forename: Delfino
authors.initials: D
authors.lastname: Alonso
authors.affiliation: Instituto Nacional de Enfermedades Respiratorias, Mexico City, Mexico.
authors.forename: Emilio
authors.initials: E
authors.lastname: Barrientos
authors.affiliation: Instituto Nacional de Enfermedades Respiratorias, Mexico City, Mexico.
authors.forename: Miguel
authors.initials: M
authors.lastname: Gaxiola
authors.affiliation: Instituto Nacional de Enfermedades Respiratorias, Mexico City, Mexico.
authors.forename: Carmen
authors.initials: C
authors.lastname: Navarro
authors.affiliation: Instituto Nacional de Enfermedades Respiratorias, Mexico City, Mexico. Electronic address: moiselman@salud.gob.mx.
authors.forename: Moisés
authors.initials: M
authors.lastname: Selman
mesh_terms: D000368:Aged; D016022:Case-Control Studies; D015331:Cohort Studies; D005260:Female; D006801:Humans; D006976:Hypertension, Pulmonary / Q000150:complications* / Q000401:mortality / Q000503:physiopathology; D054990:Idiopathic Pulmonary Fibrosis / Q000150:complications* / Q000401:mortality* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D011651:Pulmonary Artery; D011656:Pulmonary Emphysema / Q000453:epidemiology* / Q000401:mortality* / Q000503:physiopathology; D012123:Pulmonary Ventilation; D012307:Risk Factors; D012907:Smoking; D015996:Survival Rate