Aims: 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.
Conclusion: Lung function does not appear to be a valid criterion for assigning COPD management directed at patients with recurrent exacerbation.