+1 Recommend
1 collections
      • Record: found
      • Abstract: found
      • Article: found
      Is Open Access

      Impact of mild exacerbation on COPD symptoms in a Japanese cohort

      Read this article at

          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.



          Patients with COPD might not report mild exacerbation. The frequency, risk factors, and impact of mild exacerbation on COPD status are unknown.


          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).


          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.


          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.

          Related collections

          Most cited references 27

          • Record: found
          • Abstract: found
          • Article: found
          Is Open Access

          Mechanisms and impact of the frequent exacerbator phenotype in chronic obstructive pulmonary disease

          Exacerbations of chronic obstructive pulmonary disease (COPD) are important events that carry significant consequences for patients. Some patients experience frequent exacerbations, and are now recognized as a distinct clinical subgroup, the ‘frequent exacerbator’ phenotype. This is relatively stable over time, occurs across disease severity, and is associated with poorer health outcomes. These patients are therefore a priority for research and treatment. The pathophysiology underlying the frequent exacerbator phenotype is complex, with increased airway and systemic inflammation, dynamic lung hyperinflation, changes in lower airway bacterial colonization and a possible increased susceptibility to viral infection. Frequent exacerbators are also at increased risk from comorbid extrapulmonary diseases including cardiovascular disease, gastroesophageal reflux, depression, osteoporosis and cognitive impairment. Overall these patients have poorer health status, accelerated forced expiratory volume over 1 s (FEV1) decline, worsened quality of life, and increased hospital admissions and mortality, contributing to increased exacerbation susceptibility and perpetuation of the frequent exacerbator phenotype. This review article sets out the definition and importance of the frequent exacerbator phenotype, with a detailed examination of its pathophysiology, impact and interaction with other comorbidities.
            • Record: found
            • Abstract: found
            • Article: not found

            Underreporting exacerbation of chronic obstructive pulmonary disease in a longitudinal cohort.

            Unreported exacerbations and failure to seek medical attention may have consequences on the health of patients with chronic obstructive pulmonary disease. This study aims to determine the incidence of reported and unreported exacerbations, to identify predictors of reporting, and to compare the impact of reported and unreported exacerbations on health status. The study is based on a multicenter Canadian cohort of patients with chronic obstructive pulmonary disease. Patients completed a daily diary from which exacerbations were defined as a worsening of at least one key symptom (dyspnea, sputum amount, sputum color) recorded on at least 2 consecutive days. Patients were asked to contact the study center if there was a sustained worsening of symptom. Reported exacerbations were events that led to contacting study center or health care visit. The study enrolled 421 patients. The overall incidence of diary exacerbations was 2.7 per person per year, but only 0.8 per person per year was reported. Predictors of reporting included age (HR [hazard ratio], 0.90; 95% confidence interval [CI], 0.81-0.98 per 5-yr increase), FEV(1)% predicted (HR, 0.84; 95% CI, 0.70-0.99 per 10% increase), number of symptoms at onset (HR, 1.59; 95% CI, 1.37-1.84 per additional symptom), and time of the week (HR, 0.35; 95% CI, 0.22-0.56 weekend vs. weekday). There was a clinically important decline in health status for 52% of patients with reported exacerbation and 43% with unreported exacerbations. This study has shown that less than one-third of the exacerbations were reported. The number of symptoms at onset was the most important predictor of reporting an exacerbation, and both reported and unreported exacerbations had an impact on health status.
              • Record: found
              • Abstract: found
              • Article: not found

              Independent effect of depression and anxiety on chronic obstructive pulmonary disease exacerbations and hospitalizations.

              Depression and anxiety are significant comorbid and potentially modifiable conditions in chronic obstructive pulmonary disease (COPD), but their effects on exacerbations are not clear. To investigate the independent effect of depression and anxiety on the risk of COPD exacerbations and hospitalizations. A multicenter prospective cohort study in 491 patients with stable COPD in China. Multivariate Poisson and linear regression analyses were used, respectively, to estimate adjusted incidence rate ratios (IRRs) and adjusted effects on duration of events. Depression and anxiety were measured using the Hospital Anxiety and Depression Scale (HADS) at baseline. Other measurements included sociodemographic, clinical, psychosocial, and treatment characteristics. Patients were then monitored monthly for 12 months to document the occurrence and characteristics of COPD exacerbations and hospitalizations. Exacerbation was determined using both symptom-based (worsening of > or =1 key symptom) and event-based definitions (> or =1 symptom worsening plus > or =1 change in regular medications). A total of 876 symptom-based and 450 event-based exacerbations were recorded, among which 183 led to hospitalization. Probable depression (HADS depression score > or = 11) was associated with an increased risk of symptom-based exacerbations (adjusted IRR, 1.51; 95% confidence interval [CI], 1.01-2.24), event-based exacerbations (adjusted IRR, 1.56; 95% CI, 1.02-2.40), and hospitalization (adjusted IRR, 1.72; 95% CI, 1.04-2.85) compared with nondepression (score or = 11) than those with no anxiety (score < or = 7). This study suggests a possible causal effect of depression on COPD exacerbations and hospitalizations. Further studies are warranted to confirm this finding and to test the effectiveness of antidepressants and psychotherapies on reducing exacerbations and improving health resource utilizations.

                Author and article information

                Int J Chron Obstruct Pulmon Dis
                Int J Chron Obstruct Pulmon Dis
                International Journal of COPD
                International Journal of Chronic Obstructive Pulmonary Disease
                Dove Medical Press
                09 June 2016
                : 11
                : 1269-1278
                [1 ]Division of Pulmonary Medicine, Department of Medicine, Keio University School of Medicine, Tokyo, Japan
                [2 ]Department of Respiratory Medicine, Saitama Medical University, Saitama, Japan
                [3 ]Division of Pulmonary Medicine, Department of Medicine, Tokai University School of Medicine, Kanagawa, Japan
                Author notes
                Correspondence: Shotaro Chubachi, Division of Pulmonary Medicine, Department of Medicine, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan, Tel +81 3 5363 3406, Fax +81 3 3353 2502, Email bachibachi472000@
                © 2016 Sato et al. This work is published and licensed by Dove Medical Press Limited

                The full terms of this license are available at and incorporate the Creative Commons Attribution – Non Commercial (unported, v3.0) License ( By accessing the work you hereby accept the Terms. Non-commercial uses of the work are permitted without any further permission from Dove Medical Press Limited, provided the work is properly attributed.

                Original Research

                Respiratory medicine

                comorbidity, copd, chronic emphysema, copd exacerbation, quality of life


                Comment on this article