Prediction of first acute exacerbation using COPD subtypes identified by cluster analysis

Abstract

Purpose

In patients with COPD, acute exacerbation (AE) is not only an important determinant of prognosis, but also an important factor in choosing therapeutic agents. In this study, we evaluated the usefulness of COPD subtypes identified through cluster analysis to predict the first AE.

Patients and methods

Among COPD patients in the Korea COPD Subgroup Study (KOCOSS) cohort, 1,195 who had follow-up data for AE were included in our study. We selected seven variables for cluster analysis – age, body mass index, smoking status, history of asthma, COPD assessment test (CAT) score, post-bronchodilator (BD) FEV ₁ % predicted, and diffusing capacity of carbon monoxide % predicted.

Results

K-means clustering identified four clusters for COPD that we named putative asthma-COPD overlap (ACO), mild COPD, moderate COPD, and severe COPD subtypes. The ACO group (n=196) showed the second-best post-BD FEV ₁ (75.5% vs 80.9% [mild COPD, n=313] vs 52.4% [moderate COPD, n=345] vs 46.7% [severe COPD, n=341] predicted), the longest 6-min walking distance (424 m vs 405 m vs 389  m vs 365 m), and the lowest CAT score (12.2 vs 13.7 vs 15.6 vs 17.5) among the four groups. ACO group had greater risk for first AE compared to the mild COPD group (HR, 1.683; 95% CI, 1.175–2.410). The moderate COPD and severe COPD group HR values were 1.587 (95% CI, 1.145–2.200) and 1.664 (95% CI, 1.203–2.302), respectively. In addition, St. George’s Respiratory Questionnaire score (HR: 1.019; 95% CI, 1.014–1.024) and gastroesophageal reflux disease were independent factors associated with the first AE (HR: 1.535; 95% CI, 1.116–2.112).

Conclusion

Our cluster analysis revealed an exacerbator subtype of COPD independent of FEV ₁. Since these patients are susceptible to AE, a more aggressive treatment strategy is needed in these patients.

Journal

Journal ID (nlm-ta): Int J Chron Obstruct Pulmon Dis

Journal ID (iso-abbrev): Int J Chron Obstruct Pulmon Dis

Journal ID (publisher-id): COPD

Journal ID (pmc): copd

Title: International Journal of Chronic Obstructive Pulmonary Disease

Publisher: Dove

ISSN (Print): 1176-9106

ISSN (Electronic): 1178-2005

Publication date (Electronic): 28 June 2019

Publication date Collection: 2019

Volume: 14

Pages: 1389-1397

Affiliations

[1 ]Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, College of Medicine, Ewha Womans Seoul Hospital, Ewha Womans University , Seoul, Korea

[2 ]Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Seoul National University Hospital , Seoul, Korea

[3 ]Division of Pulmonary Medicine, Department of Internal Medicine, Gangnam Severance Hospital, Yonsei University College of Medicine, Yonsei University Health System , Seoul, Korea

[4 ]Division of Pulmonology, Department of Internal Medicine, Soonchunhyang University, College of Medicine , Cheonan, Korea

[5 ]Department of Pulmonary and Critical Care Medicine, Asan Medical Centre, University of Ulsan College of Medicine , Seoul, Korea

[6 ]Department of Internal Medicine, Wonju Christian Hospital, Yonsei University Wonju College of Medicine , Wonju, Korea

[7 ]Department of Internal Medicine, Konkuk University College of Medicine , Seoul, Korea

[8 ]Division of Pulmonary, Allergy and Critical Care Medicine, Department of Internal Medicine, Hallym University Medical Center, Hallym University College of Medicine , Anyang, Korea

Author notes

Correspondence: Jin Hwa LeeDivision of Pulmonary and Critical Care Medicine, Department of Internal Medicine, College of Medicine, Ewha Womans University , 260 Gonghang-daero Gangseo-gu, Seoul07804, KoreaTel [phone]Email jinhwalee@ 123456ewha.ac.kr

Article

Publisher ID: 205517

DOI: 10.2147/COPD.S205517

PMC ID: 6607981

Copyright statement: © 2019 Yoon et al.

License:

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Page count

Figures: 2, Tables: 5, References: 40, Pages: 9

Categories

Subject: Original Research