Abstract
Exacerbations are among the major factors that may affect the natural history of chronic obstructive pulmonary disease (COPD). The aim was to investigate the clinical characteristics and determinants of COPD exacerbations in our 5-year observational cohort study that had a very low exacerbation frequency.
A total of 279 patients with COPD participated in the Hokkaido COPD cohort study, and 268 subjects who had clinical data for multiple visits were analysed. Exacerbation was defined in multiple ways: patient's subjective complaint, symptom definition, requiring prescription change, requiring antibiotic treatment, and requiring hospital admission.
Exacerbation frequency (events/person/year) was 0.78±1.16 (subjective complaint), 0.24±0.47 (symptom definition), 0.20±0.43 (prescription definition), 0.13±0.28 (antibiotic definition), and 0.06±0.19 (admission definition). Exacerbation events did not significantly affect the annual decline in FEV1. A high St. George's Respiratory Questionnaire total score, especially its Activity score, and a low body mass index were strongly associated with exacerbation-free survival, exacerbation frequency, and development of recurrent exacerbations.
Despite the low exacerbation frequency in our cohort study, impaired health-related quality of life and weight loss were found to be independent risk factors for COPD exacerbations.
- ERS