title: Etiology of Bronchiectasis in a Cohort of 2047 Patients. An Analysis of the Spanish Historical Bronchiectasis Registry.
abstract: BACKGROUND
  Bronchiectasis is caused by many diseases. Establishing its etiology is important for clinical and prognostic reasons. The aim of this study was to evaluate the etiology of bronchiectasis in a large patient sample and its possible relationship with demographic, clinical or severity factors, and to analyze differences between idiopathic disease, post-infectious disease, and disease caused by other factors.
  
  
  METHODS
  Multicenter, cross-sectional study of the SEPAR Spanish Historical Registry (RHEBQ-SEPAR). Adult patients with bronchiectasis followed by pulmonologists were included prospectively. Etiological studies were based on guidelines and standardized diagnostic tests included in the register, which were later included in the SEPAR guidelines on bronchiectasis.
  
  
  RESULTS
  A total of 2,047 patients from 36 Spanish hospitals were analyzed. Mean age was 64.9years and 54.9% were women. Etiology was identified in 75.8% of cases (post-Infection: 30%; cystic fibrosis: 12.5%; immunodeficiencies: 9.4%; COPD: 7.8%; asthma: 5.4%; ciliary dyskinesia: 2.9%, and systemic diseases: 1.4%). The different etiologies presented different demographic, clinical, and microbiological factors. Post-infectious bronchiectasis and bronchiectasis caused by COPD and asthma were associated with an increased risk of poorer lung function. Patients with post-infectious bronchiectasis were older and were diagnosed later. Idiopathic bronchiectasis was more common in female non-smokers and was associated with better lung function, a higher body mass index, and a lower rate of Pseudomonas aeruginosa than bronchiectasis of known etiology.
  
  
  CONCLUSIONS
  The etiology of bronchiectasis was identified in a large proportion of patients included in the RHEBQ-SEPAR registry. Different phenotypes associated with different causes could be identified.
authors.affiliation: Servicio de Neumología, Hospital Regional Universitario de Málaga, Instituto de Biomedicina de Málaga (IBIMA), Facultad de Medicina, Universidad de Málaga, Málaga, España. Electronic address: casi1547@separ.es.
authors.forename: Casilda
authors.initials: C
authors.lastname: Olveira
authors.affiliation: Unidad de Neumología, Agencia Sanitaria Costa del Sol, Marbella, Málaga, España.
authors.forename: Alicia
authors.initials: A
authors.lastname: Padilla
authors.affiliation: Servicio de Neumología, Hospital Universitario y Politécnico La Fe⋅ CIBER de enfermedades respiratorias (CIBERes), Valencia, España.
authors.forename: Miguel-Ángel
authors.initials: MÁ
authors.lastname: Martínez-García
authors.affiliation: Unidad de Neumología, Hospital Plató, Barcelona, España.
authors.forename: David
authors.initials: D
authors.lastname: de la Rosa
authors.affiliation: Servicio de Neumología, Instituto de Investigación Sanitaria Hospital Universitario de la Princesa, Madrid, España.
authors.forename: Rosa-María
authors.initials: RM
authors.lastname: Girón
authors.affiliation: Servicio de Neumología, Hospital Josep Trueta⋅ Biomedical Research Institute (IDIBGI), Girona, España.
authors.forename: Montserrat
authors.initials: M
authors.lastname: Vendrell
authors.affiliation: Servicio de Neumología, Hospital Ramón y Cajal, Madrid, España.
authors.forename: Luis
authors.initials: L
authors.lastname: Máiz
authors.affiliation: Servicio de Neumología, Hospital General San Jorge, Huesca, España.
authors.forename: Luis
authors.initials: L
authors.lastname: Borderías
authors.affiliation: Servicio de Neumología, Hospital Clínic i Provincial, Barcelona, España.
authors.forename: Eva
authors.initials: E
authors.lastname: Polverino
authors.affiliation: Servicio de Neumología, Hospital de Sagunto, Sagunto, Valencia, España.
authors.forename: Eva
authors.initials: E
authors.lastname: Martínez-Moragón
authors.affiliation: Instituto de Investigación Sanitaria, Hospital Universitario de la Princesa, Madrid, España.
authors.forename: Olga
authors.initials: O
authors.lastname: Rajas
authors.affiliation: Complejo Hospitalario Universitario de Granada, Granada, España.
authors.forename: Francisco
authors.initials: F
authors.lastname: Casas
authors.affiliation: Servicio de Neumología, Hospital Universitario de Salamanca, Salamanca, España.
authors.forename: Rosa
authors.initials: R
authors.lastname: Cordovilla
authors.affiliation: Servicio de Neumología, Hospital Vall d'Hebron, Barcelona, España.
authors.forename: Javier
authors.initials: J
authors.lastname: de Gracia
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001249:Asthma / Q000150:complications; D001987:Bronchiectasis / Q000453:epidemiology / Q000209:etiology*; D015897:Comorbidity; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D050177:Overweight / Q000453:epidemiology; D011552:Pseudomonas Infections / Q000150:complications / Q000382:microbiology; D011550:Pseudomonas aeruginosa / Q000302:isolation & purification; D029424:Pulmonary Disease, Chronic Obstructive / Q000150:complications; D012042:Registries; D012141:Respiratory Tract Infections / Q000150:complications; D012907:Smoking / Q000009:adverse effects; D013030:Spain / Q000453:epidemiology
keywords: Bronchiectasis; Bronquiectasias; Clinical phenotype; Etiology; Etiología; Fenotipo clínico; Función pulmonar; Idiopathic; Idiopáticas; Lung function