title: Expansion of the prognostic assessment of patients with chronic obstructive pulmonary disease: the updated BODE index and the ADO index.
abstract: BACKGROUND
  The BODE index (including body-mass index, airflow obstruction, dyspnoea, and exercise capacity) was an important contribution to the prognostic assessment of patients with chronic obstructive pulmonary disease (COPD). However, no study has assessed whether the risk of mortality predicted by the BODE index matches the observed mortality in different populations. We assessed the calibration of the BODE index, updated it to improve its calibration, and developed and validated a simplified index for use in primary-care settings.
  
  
  METHODS
  We included 232 patients from the Swiss Barmelweid cohort with longstanding and severe COPD and 342 patients from the Spanish Phenotype and Course of COPD cohort study who had had their first hospital admission due to moderate-to-severe COPD. In both cohorts we compared the observed 3-year risk of all-cause mortality with the risk predicted by the BODE index. We then updated the BODE index and developed a simplified ADO index (including age, dyspnoea, and airflow obstruction) from the Swiss cohort, and validated both in the Spanish cohort.
  
  
  RESULTS
  Calibration of the BODE index was poor, with relative underprediction of 3-year risk of mortality by 36% in the Swiss cohort (median predicted risk 21.7% [IQR 12.7-31.7] vs 34.1% observed risk; p=0.013) and relative overprediction by 39% in the Spanish cohort (16.7% [12.7-31.7] vs 12.0%; p=0.035). The 3-year risk of mortality predicted by both the updated BODE (median 10.7% [8.1-13.8]) and ADO indices (11.8% [9.1-14.3]) matched the observed mortality in the Spanish cohort well (p=0.99 and p=0.98, respectively).
  
  
  CONCLUSIONS
  Both the updated BODE and ADO indices could lend support to the prognostic assessment of patients with COPD in specialised and primary-care settings. Such assessment enhances the targeting of treatments to individual patients.
  
  
  BACKGROUND
  Swiss National Science Foundation; Klinik Barmelweid; Fondo de Investigación Sanitaria Ministry of Health, Spain; Agència d'Avaluació de Tecnologia i Recerca Mèdiques, Catalonia Government; Spanish Society of Pneumology and Thoracic Surgery; Catalan Foundation of Pneumology; Red RESPIRA; Red RCESP; Fondo de Investigación Sanitaria; Fondo de Investigación Sanitaria; Fundació La Marató de TV3; Novartis Farmacèutica, Spain.
authors.affiliation: Department of Epidemiology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA. mpuhan@jhsph.edu
authors.forename: Milo A
authors.initials: MA
authors.lastname: Puhan
authors.forename: Judith
authors.initials: J
authors.lastname: Garcia-Aymerich
authors.forename: Martin
authors.initials: M
authors.lastname: Frey
authors.forename: Gerben
authors.initials: G
authors.lastname: ter Riet
authors.forename: Josep M
authors.initials: JM
authors.lastname: Antó
authors.forename: Alvar G
authors.initials: AG
authors.lastname: Agustí
authors.forename: Federico P
authors.initials: FP
authors.lastname: Gómez
authors.forename: Roberto
authors.initials: R
authors.lastname: Rodríguez-Roisín
authors.forename: Karel G M
authors.initials: KG
authors.lastname: Moons
authors.forename: Alphons G
authors.initials: AG
authors.lastname: Kessels
authors.forename: Ulrike
authors.initials: U
authors.lastname: Held
mesh_terms: D000368:Aged; D000402:Airway Obstruction / Q000209:etiology; D015992:Body Mass Index; D002423:Cause of Death; D015331:Cohort Studies; D016002:Discriminant Analysis; D004417:Dyspnea / Q000209:etiology; D017079:Exercise Tolerance; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011320:Primary Health Care; D011379:Prognosis; D029424:Pulmonary Disease, Chronic Obstructive / Q000150:complications / Q000175:diagnosis* / Q000188:drug therapy / Q000401:mortality*; D018570:Risk Assessment / Q000379:methods* / Q000592:standards; D012720:Severity of Illness Index; D013030:Spain / Q000453:epidemiology; D013557:Switzerland / Q000453:epidemiology