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Impact of mild exacerbation on COPD symptoms in a Japanese cohort

Authors Sato M, Chubachi S, Sasaki M, Haraguchi M, Kameyama N, Tsutsumi A, Takahashi S, Nakamura H, Asano K, Betsuyaku T

Received 30 January 2016

Accepted for publication 11 April 2016

Published 9 June 2016 Volume 2016:11(1) Pages 1269—1278


Checked for plagiarism Yes

Review by Single-blind

Peer reviewers approved by Dr Charles Downs

Peer reviewer comments 2

Editor who approved publication: Dr Richard Russell

Minako Sato,1 Shotaro Chubachi,1 Mamoru Sasaki,1 Mizuha Haraguchi,1 Naofumi Kameyama,1 Akihiro Tsutsumi,1 Saeko Takahashi,1 Hidetoshi Nakamura,1,2 Koichiro Asano,3 Tomoko Betsuyaku1

1Division of Pulmonary Medicine, Department of Medicine, Keio University School of Medicine, Tokyo, 2Department of Respiratory Medicine, Saitama Medical University, Saitama, 3Division of Pulmonary Medicine, Department of Medicine, Tokai University School of Medicine, Kanagawa, Japan

Background: Patients with COPD might not report mild exacerbation. The frequency, risk factors, and impact of mild exacerbation on COPD status are unknown.
Objectives: The present study was performed to compare features between mild exacerbation and moderate or severe exacerbation in Japanese patients with COPD.
Patients and methods: An observational COPD cohort was designed at Keio University and affiliated hospitals to prospectively investigate the management of COPD comorbidities. This study analyzes data only from patients with COPD who had completed annual examinations and questionnaires over a period of 2 years (n=311).
Results: Among 59 patients with mild exacerbations during the first year, 32.2% also experienced only mild exacerbations in the second year. Among 60 patients with moderate or severe exacerbations during the first year, 40% also had the same severity of exacerbation during the second year. Findings of the COPD assessment test and the symptom component of the St George’s Respiratory Questionnaire at steady state were worse in patients with mild exacerbations than in those who were exacerbation free during the 2-year study period, although the severity of the ratio of predicted forced expiratory volume in 1 second did not differ between them. Severe airflow limitation (the ratio of predicted forced expiratory volume in 1 second <50%) and experience of mild exacerbations independently advanced the likelihood of an elevated COPD assessment test score to ≥2 per year.
Conclusion: The severity of COPD exacerbation seemed to be temporally stable over 2 years, and even mild exacerbations adversely impacted the health-related quality of life of patients with COPD.

Keywords: COPD, chronic emphysema, COPD exacerbation, quality of life, comorbidity

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