Evidence map›Paper›PMID 30464435›Full record

ReviewInternational journal of chronic obstructive pulmonary disease

Understanding low COPD exacerbation rates in Japan: a review and comparison with other countries.

Takeo Ishii, Masaharu Nishimura, Asako Akimoto, Mark H James, Paul Jones

Abstract readReview
PubMed Full text at PMC Publisher
In one paragraph

Review in International journal of chronic obstructive pulmonary disease. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 31 papers, 1 of them a synthesis that pooled it.

0numbers the graph read from it
0cells of the map it votes in
31citing papers in PubMed, 1 pooled it
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

31 citing papers in PubMed, 1 synthesis or guideline pooled it.

  1. Pooled it
  2. Effects of Individualized Step Targets on Physical Activity in COPD. A Randomized Study.International journal of chronic obstructive pulmonary disease · 2025
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  20. A Telemedicine Approach for Monitoring COPD: A Prospective Feasibility and Acceptability Cohort Study.International journal of chronic obstructive pulmonary disease · 2022
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4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

5 authors.

Takeo IshiiRespiratory Medical Affairs, Development and Medical Affairs, GSK K.K., Tokyo, Japan.
Masaharu NishimuraDepartment of Respiratory Medicine, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo, Japan.
Asako AkimotoRespiratory Medical Affairs, Development and Medical Affairs, GSK K.K., Tokyo, Japan.
Mark H JamesRespiratory Franchise (omit Medical), GlaxoSmithKline, Brentford, Middlesex, UK, paul.8.jones@gsk.com.
Paul JonesRespiratory Franchise (omit Medical), GlaxoSmithKline, Brentford, Middlesex, UK, paul.8.jones@gsk.com.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

COPD is associated with significant morbidity and is one of the leading causes of death worldwide. Periods of exacerbation, the acute worsening of symptoms, are interspersed throughout the disease's natural history and can result in increased treatment burden and hospitalization for patients with COPD. The frequency of exacerbations varies between countries, with both epidemiological studies and randomized controlled trials (RCTs) showing significant differences in observed prevalence rates. Differences in study design and the healthcare setting are likely to contribute to differences in exacerbation frequency, however the perceived rate of exacerbations in Japan is currently lower then the rest of the world. This review identified nine cohort studies and five RCTs that reported COPD annual exacerbation rates in Japan in the ranges of 0.1-2.1 and 0.33-1.79, respectively. The difference in exacerbation rate between studies appeared greater than the difference between Japan and Western countries, likely because of disparities between settings, design, and inclusion criteria. Of these, only one (Understanding the Long-Term Impacts of Tiotropium) had uniform inclusion criteria across different regions. This study found that the annual rate of exacerbation events per patient in Japan was 0.61, compared with 0.85 worldwide in the placebo groups. This review summarizes the published rates of COPD exacerbations in Japan and the rest of the world and explores the hypotheses as to why rates in Japan might be lower than other countries. These include access to medical care, variance in the associated morbidity profile, environmental factors, diagnostic crossover with related diseases, and differences in study design (including the underreporting of COPD exacerbations in Japan). Understanding the reasons why COPD exacerbation rates appear lower in Japan could help clinicians to recognize and modify treatment behaviors, which may lead to improved patient outcomes in all populations.

Indexed as

AgedAged, 80 and overComorbidityDisease ProgressionEnvironmentFemaleHealthcare DisparitiesHealth Status DisparitiesHumansJapanMaleMiddle AgedPrognosisPulmonary Disease, Chronic ObstructiveRisk FactorsTime Factorsasthma-COPD overlapCOPDexacerbation rateJapan

Identifiers

PMID30464435
PMCPMC6208549

What OpenQuestion holds

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Registered trials

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.