title: Retrospective observational study of trends in hospital admissions for idiopathic pulmonary fibrosis in Spain (2004-2013) using administrative data.
abstract: To assess changes in incidence, diagnostic procedures, comorbidity profiles, length of hospital stay (LOHS), economic costs and in-hospital mortality (IHM) associated with idiopathic pulmonary fibrosis (IPF).
  
  
  
  We identified patients hospitalised with IPF in Spain from 2004 to 2013. Data were collected from the National Hospital Discharge Database.
  
  
  
  The study population comprised 22 214 patients. Overall crude incidence increased from 3.82 to 6.98 admissions per 100 000 inhabitants from 2004 to 2013 (p<0.05). The percentage of lung biopsies decreased significantly from 10.68% in 2004 to 9.04% in 2013 (p<0.05). The percentage of patients with a Charlson comorbidity index ≥2 was 15.14% in 2004, increasing to 26.95% in 2013 (p<0.05). IHM decreased from 14.77% in 2004 to 13.72% in 2013 (adjusted OR 0.98; 95% CI 0.97 to 0.99). Mean LOHS was 11.87±11.18 days in 2004, decreasing to 10.20±11.12 days in 2013 (p<0.05). The mean cost per patient increased from €4838.51 in 2004 to €5410.90 in 2013 (p<0.05).
  
  
  
  The frequency of hospital admissions for IPF increased during the study period, as did healthcare costs. However, IHM and LOHS decreased.
authors.affiliation: Respiratory Department, Hospital General Universitario Gregorio Marañón, Facultad de Medicina, Universidad Complutense de Madrid (UCM), Instituto de Investigación Sanitaria Gregorio Marañón (IiSGM), Madrid, Spain.
authors.forename: Fernando
authors.initials: F
authors.lastname: Pedraza-Serrano
authors.affiliation: Preventive Medicine and Public Health Teaching and Research Unit, Department of Health Sciences, Universidad Rey Juan Carlos, Alcorcón, Madrid, Spain.|Universidad Rey Juan Carlos, Alcorcón, Madrid, Spain.
authors.forename: Ana
authors.initials: A
authors.lastname: López de Andrés
authors.affiliation: Preventive Medicine and Public Health Teaching and Research Unit, Department of Health Sciences, Universidad Rey Juan Carlos, Alcorcón, Madrid, Spain.|Universidad Rey Juan Carlos, Alcorcón, Madrid, Spain.
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Jiménez-García
authors.affiliation: Preventive Medicine and Public Health Teaching and Research Unit, Department of Health Sciences, Universidad Rey Juan Carlos, Alcorcón, Madrid, Spain.|Universidad Rey Juan Carlos, Alcorcón, Madrid, Spain.
authors.forename: Isabel
authors.initials: I
authors.lastname: Jiménez-Trujillo
authors.affiliation: Preventive Medicine and Public Health Teaching and Research Unit, Department of Health Sciences, Universidad Rey Juan Carlos, Alcorcón, Madrid, Spain.|Universidad Rey Juan Carlos, Alcorcón, Madrid, Spain.
authors.forename: Valentín
authors.initials: V
authors.lastname: Hernández-Barrera
authors.affiliation: Respiratory Department, Hospital General Universitario Gregorio Marañón, Facultad de Medicina, Universidad Complutense de Madrid (UCM), Instituto de Investigación Sanitaria Gregorio Marañón (IiSGM), Madrid, Spain.
authors.forename: Gema
authors.initials: G
authors.lastname: Sánchez-Muñoz
authors.affiliation: Respiratory Department, Hospital General Universitario Gregorio Marañón, Facultad de Medicina, Universidad Complutense de Madrid (UCM), Instituto de Investigación Sanitaria Gregorio Marañón (IiSGM), Madrid, Spain.
authors.forename: Luis
authors.initials: L
authors.lastname: Puente-Maestu
authors.affiliation: Respiratory Department, Hospital General Universitario Gregorio Marañón, Facultad de Medicina, Universidad Complutense de Madrid (UCM), Instituto de Investigación Sanitaria Gregorio Marañón (IiSGM), Madrid, Spain.
authors.forename: Javier
authors.initials: J
authors.lastname: de Miguel-Díez
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001706:Biopsy / Q000639:trends; D015897:Comorbidity; D005260:Female; D017721:Hospital Costs / Q000639:trends; D017052:Hospital Mortality / Q000639:trends*; D006801:Humans; D054990:Idiopathic Pulmonary Fibrosis / Q000175:diagnosis / Q000453:epidemiology* / Q000473:pathology / Q000628:therapy; D015994:Incidence; D007902:Length of Stay / Q000639:trends*; D008168:Lung / Q000473:pathology; D008297:Male; D008875:Middle Aged; D063087:Noninvasive Ventilation / Q000639:trends; D010343:Patient Admission / Q000639:trends*; D012189:Retrospective Studies; D013030:Spain / Q000453:epidemiology
keywords: cost; hospitalization; idiopathic pulmonary fibrosis; in-hospital mortality; length of hospital stay