One‐year clinically important deterioration and long‐term clinical course in Japanese patients with COPD: a multicenter observational cohort study

Abstract Background Chronic obstructive pulmonary disease (COPD) is a heterogeneous with complex progression of many clinical presentations, and clinically important deterioration (CID) has been proposed in the Western studies as composite endpoint progression. The aim this study was to investigate relationships between 1-year CID following long-term outcomes Japanese patients COPD who have reported different characteristics compared Westerners. Methods Among enrolled Hokkaido cohort study, 259 did not drop out within first year were analyzed study. Two definitions used. Definition 1 comprised ≥ 100 mL decrease forced expiratory volume s (FEV ), 4-unit increase St George’s Respiratory Questionnaire (SGRQ) score from baseline, or moderate severe exacerbation. For 2, thresholds for FEV SGRQ components doubled. presence evaluated enrollment, association 4-year risk exacerbations 9-year mortality. Results Patients using 1, but any single component, during had significantly worse mortality those without CID. 2 showed similar trend on mortality, shorter exacerbation-free survival Conclusions Adoption beneficial useful way assessment even population COPD. definition might be optimized according observation period