title: Defining COPD exacerbations: impact on estimation of incidence and burden in primary care.
abstract: OBJECTIVE
  To investigate the impact of definition on the incidence of chronic obstructive pulmonary disease (COPD) exacerbations in primary care.
  
  
  METHODS
  In a one-year prospective, observational study, data from diary cards were used to determine the incidence of symptom- and healthcare-defined exacerbations. One hundred and twenty seven patients completed > or =80% of days in the diary card and were included in the analysis.
  
  
  RESULTS
  Incidence of COPD exacerbation varied according to definition. Mean yearly rates were 2.3 for symptom- and 2.8 for healthcare-defined exacerbations. Although patients with FEV(1) <50% had a higher mean yearly rate of healthcare-defined exacerbations than those with FEV(1) > or =50% (3.2 vs 2.3; p=0.003), patients with less severe disease reported recurrent exacerbations. There was limited agreement between symptom- and healthcare-defined exacerbations.
  
  
  CONCLUSIONS
  Lung function does not appear to be a valid criterion for assigning COPD management directed at patients with recurrent exacerbation.
authors.affiliation: University Hospital, Aintree, Liverpool, UK.
authors.forename: John F
authors.initials: JF
authors.lastname: O'Reilly
authors.forename: Angela E
authors.initials: AE
authors.lastname: Williams
authors.forename: Kay
authors.initials: K
authors.lastname: Holt
authors.forename: Leanne
authors.initials: L
authors.lastname: Rice
mesh_terms: D000368:Aged; D005260:Female; D005541:Forced Expiratory Volume; D017048:Health Care Costs; D006801:Humans; D008297:Male; D009819:Office Visits / Q000191:economics / Q000706:statistics & numerical data; D011320:Primary Health Care / Q000191:economics / Q000706:statistics & numerical data*; D011446:Prospective Studies; D029424:Pulmonary Disease, Chronic Obstructive / Q000191:economics / Q000503:physiopathology*; D011795:Surveys and Questionnaires