History of Respiratory Events Prior to a First COPD Diagnosis and Future Exacerbations: A Longitudinal Observational Cohort Database Study in Japan

Abstract

Background

Little is known about the association between respiratory events prior to diagnosis of chronic obstructive pulmonary disease (COPD) and future clinical outcomes in Japan. We investigated the association between pre-COPD diagnosis respiratory events and the incidence of exacerbations in a cohort of newly diagnosed COPD patients in Japan.

Patients and Methods

Data were retrieved from the JMDC claims database. Patients ≥40 years old with a first COPD diagnosis (≥1 hospitalization or ≥2 outpatient claims for COPD) between 2010 and 2016 were included. The incidence rate (IR) of exacerbations in patients with or without any respiratory event (including lower respiratory tract infection and respiratory failure) in the year preceding diagnosis was compared. A negative binomial model explored the association between pre-diagnosis respiratory event and IR ratio (IRR) of exacerbations.

Results

A total of 20,212 patients newly diagnosed with COPD were identified: 61% male, mean age 55 years (SD 9); of these, 955 (4.7%) had experienced ≥1 respiratory event in the year preceding diagnosis. Median duration of follow-up was 3.3 years during which the IR of exacerbations was 0.31 per patient-year (95% confidence interval [CI] 0.29–0.33) in patients with respiratory event, and 0.11 (95% CI 0.10–0.13) in patients without. The IR for severe exacerbation was nearly 10 times greater in patients with respiratory event versus without. Experiencing respiratory event pre-diagnosis was independently associated with an increased IRR of future moderate-to-severe exacerbation (adjusted IRR, 2.7; 95% CI 2.3–3.1).

Conclusion

Patients experiencing respiratory events in the year preceding COPD diagnosis should be considered at-risk of worse clinical COPD outcomes.

Keywords:

• COPD diagnosis
• lower respiratory tract infection
• exacerbation
• outcome

Abbreviations

AECOPD, acute exacerbations of COPD; CI, confidence interval; COPD, chronic obstructive pulmonary disease; International Classification of Diseases, 10th edition; ICS, inhaled corticosteroids; IQR, interquartile range; IR, incidence rate; IRR, incidence rate ratio; LABA, long-acting β2-agonist; LAMA, long-acting muscarinic antagonists; LRTI, lower respiratory tract infection; RR, risk ratio; SABA, short-acting β2-agonist; SAMA, short-acting muscarinic antagonist; SD, standard deviation.

Data Sharing Statement

Data underlying the findings described in this manuscript may be obtained in accordance with AstraZeneca’s data sharing policy described at https://astrazenecagrouptrials.pharmacm.com/ST/Submission/Disclosure.

Ethics Approval and Informed Consent

Patient-level data were provided after anonymization. The need for informed consent was waived, as data available in the database were standardized and anonymized. The study was approved by the Research Institute of Healthcare Data Science (Approval No. RI2020010).

Consent for Publication

The study used electronic healthcare records routinely collected as part of usual care. No consent for publication was required from patients as the manuscript contains no identifiable details such as photograph(s) and/or videos and/or case history and/or details within the text.

Acknowledgments

The authors would like to thank Masato Ishida and Ai Hayashi, former employees of AstraZeneca, for their contributions to the study.

Author Contributions

All authors made a significant contribution to the work reported, whether that is in the conception, study design, execution, acquisition of data, analysis and interpretation, or in all these areas; took part in drafting, revising or critically reviewing the article; gave final approval of the version to be published; have agreed on the journal to which the article has been submitted; and agree to be accountable for all aspects of the work.

Disclosure

BD, NM, CN, and HM are employees of AstraZeneca and hold stock and/or options in the company. RZ is a former employee of Evidera, which was contracted by AstraZeneca to conduct the study. SG, DL, and SH are employees of Evidera, which was contracted by AstraZeneca to conduct the study. SM has received lecture fees from AstraZeneca, GSK, Nippon Boehringer Ingelheim, Novartis Pharma, Teijin Pharma and grants from ROHTO Pharmaceutical Co., Ltd. The authors report no other conflicts of interest in this work.

Additional information

Funding

This study was funded by AstraZeneca.