Association between exercise and risk of cardiovascular diseases in patients with non-cystic fibrosis bronchiectasis.

BACKGROUND: Although cardiovascular comorbidities negatively impact survival in patients with bronchiectasis, there is limited evidence to recommend exercise in this population. We aimed to evaluate whether exercise habit changes are related to reduced cardiovascular disease risk and explore an optimal exercise amount. METHODS: This study identified 165,842 patients with newly diagnosed bronchiectasis during 2010-2016 who underwent two health examinations and were followed up until December 2020. The exposure was the change in weekly habits of moderate- or vigorous-intensity physical activity between the two examinations, classified into non-exercisers and exercisers (further classified into new exercisers, exercise dropouts, and exercise maintainers). The amount of exercise was measured using metabolic equivalents of task (MET). The outcome was the incidence of myocardial infarction (MI) or stroke. RESULTS: During a mean of 6.2 ± 2.1 follow-up years, 4,233 (2.6%) and 3,745 (2.3%) of patients with bronchiectasis had MI or stroke, respectively. Compared to non-exercisers, exercisers had a significantly lower risk of MI or stroke by 9-28% (p < 0.001 for both). Among exercisers, exercise maintainers showed the lowest risk of MI (adjusted hazard ratio [aHR], 0.72; 95% confidence interval [CI], 0.64-0.81) and stroke (aHR, 0.72; 95% CI, 0.64-0.82) compared to non-exercisers. Regarding exercise amount, a significant risk reduction was observed only in patients with bronchiectasis who exercised for ≥ 500 MET-min/wk. CONCLUSION: Exercise was associated with a reduced risk of cardiovascular diseases in patients with bronchiectasis. In particular, the risk was lowest in exercise maintainers, and cardiovascular risk reduction was significant when exercising more than 500 MET-min/wk.

Chronic Obstructive Pulmonary Disease is Associated with a More Symptomatic Burden and Severe Presentation of COVID-19: A Korean National COVID-19 Cohort Study.

Insufficient data are available on comprehensive evaluation of demographics, symptoms or signs, laboratory findings, and disease course in patients with coronavirus disease 2019 (COVID-19) and chronic obstructive pulmonary disease (COPD). We aimed to evaluate whether COPD patients are more prone to severe COVID-19 compared with those without COPD. We also investigate the clinical characteristics and disease course of COVID-19 in patients with COPD versus those without COPD. Patients were selected from a Korean nationwide cohort of 5,628 patients with confirmed COVID-19 and who had completed treatment or quarantine by April 30, 2020; 3,673 patients aged 40 years or older were included in this study. COPD was diagnosed using patient reports of physician-diagnosed COPD. During the study period, all patients with COVID-19 in Korea were hospitalized following the national health policy. Of the study participants, 38 (1.0%) had COPD. Regarding initial symptoms, COPD patients with COVID-19 showed greater sputum production (50.0% vs. 29.8%, p < 0.01) and dyspnea (36.8% vs. 14.9%, p < 0.01) than those without COPD. In addition, patients with COPD were more likely to receive oxygen therapy or non-invasive ventilation (29.0% vs. 13.7%, p = 0.01) and had a higher mortality (21.1% vs. 6.4%, p < 0.01) than those without COPD. After adjusting for age, sex, body mass index, and comorbidities, COPD patients showed increased risk of severe COVID-19 compared with those without COPD. Our nationwide study showed that COVID-19 patients with COPD have higher symptomatic burden and more severe disease course than those without COPD.

Interstitial lung disease increases susceptibility to and severity of COVID-19.

BACKGROUND: There are limited data regarding the relationship between interstitial lung disease (ILD) and the natural course of COVID-19. In this study, we investigate whether patients with ILD are more susceptible to COVID-19 than those without ILD and evaluate the impact of ILD on disease severity in patients with COVID-19. METHODS: A nationwide cohort of patients with COVID-19 (n=8070) and a 1:15 age-, sex- and residential area-matched cohort (n=121 050) were constructed between 1 January 2020 and 30 May 2020 in Korea. We performed a nested case-control study to compare the proportions of patients with ILD between the COVID-19 cohort and the matched cohort. Using the COVID-19 cohort, we also evaluated the risk of severe COVID-19 in patients with ILD versus those without ILD. RESULTS: The proportion of patients with ILD was significantly higher in the COVID-19 cohort than in the matched cohort (0.8% versus 0.4%; p<0.001). The odds of having ILD was significantly higher in the COVID-19 cohort than in the matched cohort (adjusted OR 2.02, 95% CI 1.54-2.61). Among patients in the COVID-19 cohort, patients with ILD were more likely to have severe COVID-19 than patients without ILD (47.8% versus 12.6%), including mortality (13.4% versus 2.8%) (all p<0.001). The risk of severe COVID-19 was significantly higher in patients with ILD than in those without ILD (adjusted OR 2.23, 95% CI 1.24-4.01). CONCLUSION: The risks of COVID-19 and severe presentation were significantly higher in patients with ILD than in those without ILD.

A case report of allergic bronchopulmonary mycosis caused by Alternaria alternata in colonization of Aspergillus.

BACKGROUND: Allergic bronchopulmonary aspergillosis (ABPA) is a pulmonary disease caused by a complex hypersensitivity reaction to colonization of the airways with various fungi. ABPA caused by Alternaria alternata, other than Aspergillus spp., is named Allergic bronchopulmonary mycosis (ABPM). OBJECTIVE: To describe the first case of ABPM caused by Alternaria alternata in East Asia. METHODS: Case report. RESULTS: A 58-year-old female visited our hospital due to an abnormal chest x-ray, following chest computed tomography (CT) revealed consolidation in the left lower lobe. On laboratory finding, eosinophil count and total IgE level were high. The skin prick test and specific IgE for Alternaria alternata were positive. After diagnosis of ABPM, the patient was treated with prednisolone without antifungal agents, and her chest image was much improved. CONCLUSIONS: Aspergillus is most common etiology of allergic pulmonary disease, however, Alternaria should be considered even though positive culture of Aspergillus spp.

Burden of male hardcore smokers and its characteristics among those eligible for lung cancer screening.

BACKGROUND: There are few data available about hardcore smokers and their behavioral characteristics among the lung cancer screening (LCS) population. The study investigated the burden of hardcore smokers within the LCS population, and determine the characteristics of hardcore smokers using nationally representative data in South Korea. METHODS: We used data from 2007 to 2012 from the Korean National Health and Nutrition Examination Survey. This study enrolled current male smokers aged 55-74 years. Among them, subjects eligible for LCS were defined as these populations with smoking histories of at least 30 PY. Hardcore smoking was defined as smoking >15 cigarettes per day, with no plan to quit, and having made no attempt to quit. Multivariate logistic regression analyses were used to estimate associations between hardcore smokers and various sociodemographic and other variables. RESULTS: The proportion of hardcore smokers among those who met LCS eligibility criteria decreased from 2007 to 2012 (from 39.07 to 29.47% of the population) but did not change significantly thereafter (P = 0.2770), and that proportion was consistently 10-15% higher than that of hardcore smokers among all male current smokers. The proportion without any plan to quit smoking decreased significantly from 54.35% in 2007 to 38.31% in 2012. However, the smokers who had made no intentional quit attempt in the prior year accounted for more than half of those eligible for LCS, and the proportion of such smokers did not change significantly during the study period (50.83% in 2007 and 51.03% in 2012). Multivariate logistic regression analyses showed that hardcore smokers were older (OR = 1.05, 95% confidence interval [CI] 1.01-1.09) than non-hardcore smokers. Hardcore smokers exhibited higher proportion of depression (OR = 6.55, 95% CI 1.75-24.61) and experienced extreme stress more frequently (OR = 1.93, 95% CI 1.13-3.29). Smokers who did not receive smoking cessation education within the past year were significantly more likely to be hardcore smokers (OR = 4.15, 95% CI 1.30-13.22). CONCLUSIONS: It is important to identify a subset of smokers unwilling or minimally motivated to quit within the context of lung cancer screening. Anti-smoking education should be enhanced to influence hardcore smokers' behavior.

Neutrophil Gelatinase-Associated Lipocalin for Predicting Intensive Care Unit Admission and Mortality in Patients with Pneumonia.

Pneumonia is one of the most common causes of hospital admissions and mortality, and it is responsible for significant socioeconomic burden worldwide. Neutrophil gelatinase-associated lipocalin (NGAL) is a 25-kDa protein, which is involved in iron trafficking and has chemostatic and bacteriostatic effects. NGAL is also known as an early marker of many inflammatory diseases. However, little is known about the role of NGAL in the management of pneumonia. Thus, this study aimed to investigate whether plasma NGAL levels can predict intensive care unit (ICU) admission and in-hospital mortality in patients with pneumonia. This retrospective observational study included 241 adults hospitalized with pneumonia who underwent NGAL measurement. We compared the prognostic values of plasma NGAL with pneumonia severity index (PSI) for prediction of ICU admission and in-hospital mortality. Of 241 patients, 47 (19.5%) died during hospital admission. There was no significant difference between NGAL and PSI for predicting ICU admission (area under the receiver operating characteristic curve [AUC] of log NGAL vs. PSI, P > 0.999). Although log NGAL was useful in predicting in-hospital mortality, its ability was inferior to that of PSI (AUC of log NGAL vs. PSI, P = 0.008). Multivariable analysis revealed that log NGAL was significantly associated with ICU admission (adjusted odds ratio = 10.76, P < 0.001) and in-hospital mortality (adjusted odds ratio = 5.04, P = 0.004). These results suggest that plasma NGAL level is a useful biomarker for predicting ICU admission and mortality in hospitalized patients with pneumonia.

Increased mortality in patients with corticosteroid-dependent asthma: a nationwide population-based study.

INTRODUCTION: Chronic systemic corticosteroid (CS) therapy is associated with an increased risk of mortality in patients with many chronic diseases. However, it has not been elucidated whether chronic systemic CS therapy is associated with increased mortality in patients with asthma. The aim of this study was to determine the effects of chronic systemic CS therapy on long-term mortality in adult patients with asthma. METHODS: A population-based matched cohort study of males and females aged ≥18 years with asthma was performed using the Korean National Health Insurance Service database from 2005 to 2015. Hazard ratio (HR) with 95% confidence interval for all-cause mortality among patients in the CS-dependent cohort (CS use ≥6 months during baseline period) relative to those in the CS-independent cohort (CS use <6 months during baseline period) was evaluated. RESULTS: The baseline cohort included 466 941 patients with asthma, of whom 8334 were CS-dependent and 458 607 were CS-independent. After 1:1 matching, 8334 subjects with CS-independent asthma were identified. The HR of mortality associated with CS-dependent asthma relative to CS-independent asthma was 2.17 (95% CI 2.04-2.31). In patients receiving low-dose CS, the HR was 1.84 (95% CI 1.69-2.00); in patients receiving high-dose CS, the HR was 2.56 (95% CI 2.35-2.80). CONCLUSIONS: In this real-world, clinical practice, observational study, chronic use of systemic CS was associated with increased risk of mortality in patients with asthma, with a significant dose-response relationship between systemic CS use and long-term mortality.

Improvement in Ventilation-Perfusion Mismatch after Bronchoscopic Lung Volume Reduction: Quantitative Image Analysis.

Purpose To evaluate whether bronchoscopic lung volume reduction (BLVR) increases ventilation and therefore improves ventilation-perfusion (V/Q) mismatch. Materials and Methods All patients provided written informed consent to be included in this study, which was approved by the Institutional Review Board (2013-0368) of Asan Medical Center. The physiologic changes that occurred after BLVR were measured by using xenon-enhanced ventilation and iodine-enhanced perfusion dual-energy computed tomography (CT). Patients with severe emphysema plus hyperinflation who did not respond to usual treatments were eligible. Pulmonary function tests, the 6-minute walking distance (6MWD) test, quality of life assessment, and dual-energy CT were performed at baseline and 3 months after BLVR. The effect of BLVR was assessed with repeated-measures analysis of variance. Results Twenty-one patients were enrolled in this study (median age, 68 years; mean forced expiratory volume in 1 second [FEV1], 0.75 L ± 0.29). After BLVR, FEV1 (P < .001) and 6MWD (P = .002) improved significantly. Despite the reduction in lung volume (-0.39 L ± 0.44), both ventilation per voxel (P < .001) and total ventilation (P = .01) improved after BLVR. However, neither perfusion per voxel (P = .16) nor total perfusion changed significantly (P = .49). Patients with lung volume reduction of 50% or greater had significantly better improvement in FEV1 (P = .02) and ventilation per voxel (P = .03) than patients with lung volume reduction of less than 50%. V/Q mismatch also improved after BLVR (P = .005), mainly owing to the improvement in ventilation. Conclusion The dual-energy CT analyses showed that BLVR improved ventilation and V/Q mismatch. This increased lung efficiency may be the primary mechanism of improvement after BLVR, despite the reduction in lung volume. © RSNA, 2017 Online supplemental material is available for this article.

Prevalence and Risk Factors of Respiratory Viral Infections in Exacerbations of Chronic Obstructive Pulmonary Disease.

Exacerbations of chronic obstructive pulmonary disease (COPD) lead to high morbidity and mortality. Respiratory virus infection is considered as one of the important causes of COPD exacerbations. The aim of this study was to assess the prevalence of respiratory virus infection in COPD exacerbations and to find the factors associated with susceptibility to viral infections. Furthermore, we tried to examine if COPD exacerbations caused by viral infections have more severe clinical outcomes in comparison with those with non-viral causes. We enrolled the patients with acute exacerbations of COPD who were hospitalized in a university hospital, over a 2-year period. Nasopharyngeal swabs were taken and viruses were identified by multiplex polymerase chain reaction. A total of 278 episodes of COPD exacerbations were recorded in 213 patients with COPD (number of females = 73). Among the COPD exacerbations, viral infection was detected in 78 episodes (28.1%) from 67 subjects. The most common virus was rhinovirus (38.8%), followed by respiratory syncytial virus, coronavirus, influenza A, parainfluenza, adenovirus and metapneumovirus. In multivariate regression analysis adjusting for sex, age, BMI, lung function and history of exacerbations, female subjects were found to be significantly associated with viral infections in COPD exacerbations (Odds ratio 2.58, 95%CI 1.25-5.31, P = 0.010). The severity of COPD exacerbations were not different between positive and negative viral detections. In conclusion, the prevalence of viral infection was 28.1% in the hospitalized patients with COPD exacerbations. Moreover, female subjects are at significantly higher risk for viral infections in COPD exacerbations.

Evolving Early Lung Cancers Detected During Follow-Up of Idiopathic Interstitial Pneumonia: Serial CT Features.

OBJECTIVE: The purpose of this study was to evaluate the CT characteristics of newly developed lung cancer on CT studies obtained during follow-up of idiopathic interstitial pneumonia (IIP) before the appearance of identifiable tumors to the time of detectable lung cancer and thereafter. MATERIALS AND METHODS: The study sample included 66 cancers diagnosed in 63 patients with IIP and lung cancer (59 men, four women; median age, 64 years; range, 40-85 years) between October 1998 and July 2012. Two radiologists independently reviewed 193 CT scans, determined the earliest presence of cancer and IIP, and evaluated tumor size, lobar and axial location, shape, and tumor density. Delay in clinical diagnosis and doubling time were measured with first and second follow-up CT examinations. RESULTS: Interobserver agreement was good (κ > 0.77). The median tumor size was 17 mm (range, 5-30 mm) for the 46 T1a and 20 T1b cancers. Most of the tumors (42 [63.6%]) were located in the lower lobes. Thirty-five tumors (53.0%) were at the interface between fibrotic cyst and normal lung, and 21 (31.8%) were in the midst of fibrotic lung cysts. Most of the tumors had a round or oval shape (52 [78.8%]) and were solid (62 [93.9%]). The median delay in diagnosis was 46 days (range, 8-760 days). The first median doubling time was 77 days (range, 15-525 days), and the second was 53 days (27-248). CONCLUSION: New lung cancers during CT follow-up of IIP usually appear as small solid nodules with a round or oval shape. Most cancers are located at the interface between fibrotic cyst and normal lung or in the midst of fibrotic cysts of the lower lobes of subpleural lung.

Three-month treatment response and exacerbation in chronic obstructive pulmonary disease.

The aim of this study was to investigate relationships between acute exacerbation and Forced Expiratory Volume 1 second (FEV1) improvement after treatment with combined long-acting beta-agonist (LABA) and inhaled corticosteroid (ICS) in patients with chronic obstructive pulmonary disease (COPD). A total of 137 COPD patients were classified as responders or nonresponders according to FEV1 improvement after 3 months of LABA/ICS treatment in fourteen referral hospitals in Korea. Exacerbation occurrence in these two subgroups was compared over a period of 1 yr. Eighty of the 137 COPD patients (58.4%) were classified as responders and 57 (41.6%) as nonresponders. Acute exacerbations occurred in 25 patients (31.3%) in the responder group and in 26 patients (45.6%) in the nonresponder group (P=0.086). FEV1 improvement after LABA/ICS treatment was a significant prognostic factor for fewer acute exacerbations in a multivariate Cox proportional hazard model adjusted for age, sex, FEV1, smoking history, 6 min walk distance, body mass index, exacerbation history in the previous year, and dyspnea scale.Three-month treatment response to LABA/ICS might be a prognostic factor for the occurrence of acute exacerbation in COPD patients.

Efficacy of bronchoscopic lung volume reduction by endobronchial valves in patients with heterogeneous emphysema: report on the first Asian cases.

Although many patients with severe emphysema have benefited from bronchoscopic lung volume reduction (BLVR) worldwide, experience of BLVR in Asian emphysema patients is scarce. Between July 2012 and March 2013, seven patients with advanced heterogeneous emphysema underwent BLVR in the Asan Medical Center. They had severe dyspnea and poor lung function (Modified Medical Research Council dyspnea scale 3-4; median forced expiratory volume in 1 sec [FEV1], 0.59 L [19.0 % predicted]; median 6-min walk distance [6MWD], 195 m). Endobronchial valves were inserted into the target lobe which was most hyperinflated and least perfused, and had no collateral ventilation with other lobes. Six patients showed clinical improvement after 1 month. Of them, 2 patients improved to dyspnea scale 1 and 4 patients did to scale 2 (P = 0.026). The median FEV1 increased from 0.59 to 0.89 L (51%; P = 0.028) and the median 6MWD increased from 195 to 252 m (29.2%; P = 0.028). Two patients developed a pneumothorax (one requiring drainage) and one patient experienced slight hemoptysis; however, there were no other serious adverse events. BLVR is effective in Asian advanced emphysema patients, with noted clinical improvements in lung function and exercise capacity.

Increased Risk of New-Onset Asthma After COVID-19: A Nationwide Population-Based Cohort Study.

BACKGROUND: Previous studies have suggested that respiratory virus infections may be associated with new-onset asthma. However, whether coronavirus disease 2019 (COVID-19) is associated with an increased risk of new-onset asthma remains unclear. OBJECTIVE: We aimed to evaluate whether recent COVID-19 increases the risk of new-onset asthma and whether COVID-19 vaccination could mitigate this risk. METHODS: We constructed 3 different study designs using the Korean National Health Insurance claim-based database: study 1: COVID-19-diagnosed subjects (COVID-19 cohort) and their matched controls; study 2: COVID-19-vaccinated subjects (vaccination cohort) and their matched controls; and study 3: vaccination cohort and their matched controls, excluding subjects diagnosed with COVID-19. RESULTS: In study 1, 1.6% of the COVID-19 cohort and 0.7% of the matched cohort developed new-onset asthma, with incidences of 31.28 and 14.55 per 1,000 person-years, respectively (P < .001). The COVID-19 cohort had a higher risk of new-onset asthma (adjusted hazard ratio [aHR] 2.14; 95% CI 1.88-2.45) than matched controls. In study 2, the vaccination cohort had a lower risk of new-onset asthma than the matched controls (aHR 0.82; 95% CI 0.76-0.89). However, among subjects without a COVID-19 diagnosis, COVID-19 vaccination was not associated with a reduced risk of new-onset asthma in study 3 (aHR 0.95; 95% CI 0.87-1.04). In subgroup analysis, the risk of new-onset asthma was significantly lower in fully vaccinated subjects and higher in older subjects and in those with diabetes mellitus than in their counterparts. CONCLUSIONS: The COVID-19 was associated with a higher incidence of new-onset asthma, which might be preventable by COVID-19 vaccination.

The Impact of Bronchiectasis on the Clinical Characteristics of Non-Severe Asthma.

Current literature primarily delves into the relationship between bronchiectasis and severe asthma, and only a few studies have evaluated the impact of bronchiectasis in patients with non-severe asthma. Therefore, this study investigated the clinical impact of bronchiectasis in patients with non-severe asthma. A prospective observational study of 140 non-severe asthmatic patients with (bronchiectasis group) and without bronchiectasis (control group) was conducted between September 2012 and February 2022. The bronchiectasis and control groups were compared in terms of demographics, lung function, asthma control test (ACT) results, exacerbation history, and respiratory medications. Among 140 non-severe asthmatic subjects, approximately 15.7% (n = 22) had bronchiectasis. The most common type of bronchiectasis was cylindrical type (90.7%). The left lingular division was the most frequently involved lung lobe (20.4%). There were no significant differences in the demographics (age, sex, body mass index, smoking history, and comorbidities) or ACT results between the 2 groups. The bronchiectasis group used inhaled corticosteroids/long-acting ß2-agonists (P = 0.074) and mucolytics (P < 0.001) more frequently than the control group. Compared to the control group, the bronchiectasis group had lower forced expiratory volume in 1 second (FEV1) (L) (1.9 ± 0.7 L vs. 2.3 ± 0.9 L, P = 0.039) and FEV1%predicted (67.2 ± 22.2%predicted vs. 77.1 ± 20.0%predicted, P = 0.038). The rate of hospital admission to a general ward in the preceding year was significantly higher in the bronchiectasis group compared to those of the control group (23.8% vs. 3.5%, P = 0.005) with an adjusted odds ratio of 6.308 (95% confidence interval, 1.401-28.392). Patients with non-severe asthma and bronchiectasis had lower lung function and more frequent exacerbations requiring hospitalization than those without bronchiectasis. More attention is needed for asthmatic patients with bronchiectasis, even if the asthma is not severe.

Does COVID-19 vaccination increase the risk of interstitial lung disease at a population level?

This study showed a significantly lower incidence of ILD among COVID-19 vaccinated individuals compared to unvaccinated, suggesting that the risk of COVID-19 vaccine-related ILD is not as high as previously reported https://bit.ly/3TWzzxP.

Long-Term Impacts of COVID-19 on Severe Exacerbation and Mortality in Adult Asthma: A Nationwide Population-Based Cohort Study.

BACKGROUND: In adults with asthma, the long-term impact of previous coronavirus disease 2019 (COVID-19) on severe exacerbations and mortality is unclear. OBJECTIVE: We evaluated the long-term risk of severe exacerbation and mortality in adults with asthma who recovered from COVID-19. METHODS: Using the Korean National Health Insurance claim-based database, we compared the risk of severe exacerbations (emergency room visits or hospitalization) and mortality in adults with asthma aged greater than 20 years who had recovered from COVID-19 between October 8, 2020, and December 16, 2021 (COVID-19 cohort, n = 10,739) with 1:1 propensity score-matched controls (n = 10,739). RESULTS: During a median follow-up of 87 days (range, 15-448 days), the incidence rate of severe exacerbations in the COVID-19 cohort and the matched cohort was 187.3 and 119.3 per 10,000 person-years, respectively. The COVID-19 cohort had a higher risk of severe exacerbation compared with the matched cohort (hazard ratio = 1.57; 95% CI, 1.06-2.32). During a median follow-up of 360 days (range, 15-721 days), the incidence rate of death in the COVID-19 and matched cohorts was 128.3 and 73.5 per 10,000 person-years, respectively. The COVID-19 cohort had a higher risk of death (hazard ratio = 1.76; 95% CI, 1.33-2.30) compared with the matched cohort. When further analyzed by COVID-19 severity, severe COVID-19 was associated with a 5.12-fold (95% CI, 3.27-8.01) and 7.31-fold (95% CI, 5.41-9.88) increased risk of severe exacerbation and death, respectively, but non-severe COVID-19 was not. CONCLUSIONS: Our study shows that severe COVID-19 is associated with an increased long-term risk of severe exacerbation and mortality among individuals with asthma.

Impacts of regular physical activity on hospitalisation in chronic obstructive pulmonary disease: a nationwide population-based study.

INTRODUCTION: Studies that comprehensively evaluate the association between physical activity (PA) levels, particularly by quantifying PA intensity, and healthcare use requiring emergency department (ED) visit or hospitalisation in patients with chronic obstructive pulmonary disease (COPD) are limited in Korea. METHODS: The risk of all-cause and respiratory ED visit or hospitalisation according to the presence or absence of COPD and the level of PA was evaluated in a retrospective nationwide cohort comprising 3308 subjects with COPD (COPD cohort) and 293 358 subjects without COPD (non-COPD cohort) from 2009 to 2017. RESULTS: The COPD group exhibited a higher relative risk of all-cause and respiratory ED visit or hospitalisation across all levels of PA compared with the highly active control group (≥1500 metabolic equivalents (METs)-min/week). Specifically, the highest risk was observed in the sedentary group (adjusted HR (aHR) (95% CI) = 1.70 (1.59 to 1.81) for all-cause ED visit or hospitalisation, 5.45 (4.86 to 6.12) for respiratory ED visit or hospitalisation). A 500 MET-min/week increase in PA was associated with reductions in all-cause and respiratory ED visit or hospitalisation in the COPD cohort (aHR (95% CI) = 0.92 (0.88 to 0.96) for all-cause, 0.87 (0.82 to 0.93) for respiratory cause). CONCLUSIONS: Compared with the presumed healthiest cohort, the control group with PA>1500 METs-min/week, the COPD group with reduced PA has a higher risk of ED visit or hospitalisation.