BACKGROUND: Previous studies have consistently reported a decrease in hospital admissions for respiratory diseases during the coronavirus disease 2019 (COVID-19) pandemic. However, the impact of the pandemic on idiopathic pulmonary fibrosis (IPF) admissions remains unknown.
METHODS: This study used data from the Korean National Health Insurance Service database. IPF was defined based on the International Classification of Diseases 10th Revision (ICD-10) and rare intractable disease (RID) codes. The rate of IPF admissions was calculated by dividing the number of IPF admissions by the prevalence of IPF. The rate of IPF admissions during the COVID-19 pandemic (2020-2021) was compared with the mean rate of admissions during the prepandemic period (2017-2019) and presented as the rate ratio (RR). A sensitivity analysis was conducted on patients treated with systemic corticosteroids during IPF admission.
RESULTS: In patients with IPF defined based on the ICD-10 (analysis 1), the RRs significantly decreased from March in 2020 to December 2021, except for June and September in 2020. Similarly, in patients with IPF defined based on the ICD-10 and RID (analysis 2), the RRs significantly decreased from March 2020 to December 2021, except for June and September 2020. In the sensitivity analysis of analysis 1, the RR significantly decreased in 2020 (0.93; 95%CI: 0.88-0.99; P = 0.029), whereas the RR in 2021 was not significantly different. The RRs in the sensitivity analysis of analysis 2 significantly decreased to 0.85 (0.79-0.92; P < 0.001) in 2020 and 0.82 (0.76-0.88; P < 0.001) in 2021. In the subgroup analysis, the rates of IPF admissions significantly decreased in 2020 and 2021 across both sexes, patients aged ≥ 60 years, and all household income groups.
CONCLUSIONS: The rate of IPF admissions significantly decreased during the COVID-19 pandemic. This result indicates that preventive measures against COVID-19 may effectively mitigate IPF exacerbation. Therefore, it is assumed that there is a close relationship between respiratory viral infections and IPF exacerbations.

Chronic Obstructive Pulmonary Disease (COPD) is characterized by persistent respiratory symptoms and airflow limitation. Acute exacerbation of COPD (AECOPD) is an acute worsening of respiratory symptoms, which needs additional treatment and can result in worsening health status, increasing risks of hospitalization and mortality. Therefore, it is necessary to early recognize and diagnose exacerbations of COPD. This review introduces the updated definition of COPD exacerbations, the current clinical assessment tools, and the current potential biomarkers. The application of mobile health care in COPD management for early identification and diagnosis is also included in this review.

OBJECTIVE: COPD and bronchiectasis are common causes of morbidity, particularly around exacerbation. Colonisation with respiratory pathogens can increase the frequency and severity of exacerbations. However, bacterial and viral presence at exacerbation in people with airway colonisation has not been well studied.
METHODS: A 6-month cohort study of participants (n = 30) with chronic bronchitis due to bronchiectasis (n = 26) and/or COPD (n = 13) and colonisation with Pseudomonas aeruginosa or Haemophilus influenzae was proven on two sputum cultures at exacerbation in the previous 12 months. Participants were provided self-management education and collected sputum samples daily. Sputum samples at baseline (at least 14 days before or after an exacerbation) and at each exacerbation were examined for a panel of 34 respiratory pathogens using commercially available RT-PCR kits and compared to results obtained using culture methods for the detection of bacteria.
RESULTS: Participants provided 29 baseline samples and 71 samples at exacerbation. In 17/29 baseline samples, RT-PCR analysis confirmed the organism demonstrated by culture, while 12 samples showed a discrepancy from culture results. Most exacerbations (57.7%) were not associated with acquiring new bacteria or viruses, while 19.8% showed new bacteria, 15.7% new viruses and 7% both new viruses and bacteria.
CONCLUSIONS: Over half of exacerbations were not associated with new organisms in this cohort of participants with chronic bronchitis and colonisation. However, 26.8% demonstrated a new bacterial species in sputum, which is relevant for antibiotic therapy. Baseline RT-PCR and culture results were discordant in one-third of participants.

BACKGROUND: While asthma exacerbations remain a major challenge in patient management, few animal models exist to explore the underlying mechanisms. Here, we established an animal model of asthma that can be used to study pathophysiological mechanisms and therapeutic strategies on asthma exacerbation.
METHODS: Female BALB/c mice were sensitized and exposed to PBS or Dermatophagoides pteronyssinus (DerP) extract for 11 weeks. Asthmatic phenotype was assessed through lung inflammation, bronchial hyperresponsiveness and bronchial smooth muscle remodeling. Asthmatic and control mice were exposed once or three times to poly(I:C) to simulate virus-induced inflammation.
RESULTS: Fourteen days after exposure to DerP, asthmatic mice showed resolution of inflammation with sustained bronchial hyperresponsiveness and bronchial smooth muscle remodeling compared to control. At this stage, when mice were subjected to a single exposure to poly(I:C), control and asthmatic mice were characterized by a significant increase in neutrophilic inflammation and bronchial hyperresponsiveness. When mice were repeatedly exposed to poly(I:C), control mice showed a significant decrease in neutrophilic inflammation and bronchial hyperresponsiveness, while asthmatic mice experienced worsening of these outcomes.
CONCLUSIONS: This observational study report an asthmatic mouse model that can undergo exacerbation after repeated exposure to poly(I:C). Our findings on pulmonary adaptation in control mice may also pave the way for further research into the mechanism of adaptation that may be impaired in asthma and raise the question of whether asthma exacerbation may be a loss of adaptation.

OBJECTIVE: To analyze the characteristics of adult patients admitted for asthma exacerbation and determine optimization, treatment adherence, and follow-up in clinics.
METHODS: Patients ≥ 18 years old admitted from May 2021 to June 2023 with a primary diagnosis of asthma exacerbation were included. Patients with a secondary diagnosis of asthma exacerbation and those without a confirmed diagnosis were excluded.
RESULTS: A total of 186 patients were analyzed, 63% were female, with a mean age of 49 ± 34 years, mean body mass index (BMI) of 26.4 ± 5 kg/m2, mean immunoglobulin E level of 132 ± 235 IU/mL (range: 25-2041), mean eosinophils count of 180 ± 443, and length of stay of 8.6 ± 5 days. Comparing patients with one admission to those with multiple admissions, differences were observed in age (39 ± 15 vs. 58 ± 20, p < 0.0001), BMI (25.2 ± 3 vs. 27.4 ± 4, p < 0.0003), comorbidity (15% vs. 60%, p < 0.0001), and length of stay (4.5 ± 2 vs. 11 ± 3, p < 0.0001). Of the patients, 15% had undiagnosed asthma, 28% had known asthma without maintenance therapy, 23% were managed by primary care, and 34% were followed by pneumology. The mean Test of Adherence to Inhalers (TAI) score was 42.5 ± 8 points, with 70% showing erratic non-adherence, 46% showing deliberate non-adherence, and 21% showing unconscious non-adherence.
CONCLUSIONS: The young population represents a significant percentage of admissions for asthma exacerbation due to poor follow-up in pulmonology clinics, inadequate treatment optimization, and low adherence. This study adds that it is necessary to improve the approach to asthma in primary care to optimize treatment, reduce under-diagnosis, and avoid hospital admissions.

BACKGROUND: Severe exacerbations of chronic obstructive pulmonary disease (COPD) are known to increase the risk of cardiovascular events. However, this association has not been investigated specifically in patients with COPD in Japan, whose characteristics may differ from those of Western patients (i.e., western Europe, the US, and Canada).
METHODS: This longitudinal retrospective cohort study analyzed secondary claims data and included patients aged ≥ 40 years with COPD (International Classification of Diseases-10 codes J41-J44). All exacerbations occurring during follow-up were measured. Time-dependent Cox models were used to estimate hazard ratios (HRs) for the association between time periods following an exacerbation of COPD (vs. time prior to a first exacerbation) and occurrence of a first hospitalization for a severe fatal or non-fatal cardiovascular event.
RESULTS: The analysis included 152,712 patients with COPD with a mean age of 73.8 years and 37.6% of whom were female. During a median follow-up of 37 months, 63,182 (41.4%) patients experienced ≥ 1 exacerbation and 13,314 (8.7%) patients experienced ≥ 1 severe cardiovascular event. Following an exacerbation of COPD, the risk of a severe cardiovascular event was increased in the first 30 days [adjusted HR (aHR) 1.44, 95% confidence interval (CI) 1.33-1.55] and remained elevated for 365 days post-exacerbation (aHR 1.13, 95% CI 1.04-1.23). Specifically, the risks of acute coronary syndrome or arrhythmias remained significantly increased for up to 180 days, and the risk of decompensated heart failure for 1 year.
CONCLUSIONS: Among Japanese patients with COPD, the risk of experiencing a severe cardiovascular event increased following a COPD exacerbation and remained elevated for 365 days, emphasizing the need to prevent exacerbations.

Characteristics of chronic obstructive pulmonary disease (COPD) patients with superoptimal peak inspiratory flow rates (PIFR) has not been thoroughly investigated. This study aimed to compare the characteristics between COPD patients with superoptimal PIFR and those with optimal and sub-optimal PIFR. PIFR was measured using In-Check DIAL G16 and categorized into sub-optimal (PIFR lower than that required by the patient\'s device), optimal, and superoptimal (peak PIFR ≥ 90 L/min). Considering COPD patients with sub-optimal PIFR as the reference group, analyses were performed to identify PIFR-related factors. Subgroup analysis was performed according to the forced expiratory volume in 1 s (FEV1) % of the predicted value (%pred). Among 444 post-bronchodilator-confirmed COPD patients from seven tertiary hospitals in South Korea, 98, 223, and 123 were classified into the sub-optimal, optimal, and superoptimal PIFR groups, respectively. The superoptimal PIFR group were younger, had an increased proportion of males, a higher body mass index, lowest number of comorbidities and less frequent exacerbation in the previous year, as well as the highest forced vital capacity %pred. The adjusted odds ratio for frequent exacerbation in the previous year was lower in the superoptimal PIFR group than in the sub-optimal PIFR group and was more pronounced in patients with an FEV1%pred of < 70%. COPD patients with superoptimal PIFR have clinical characteristics different from those patients with the sub-optimal and optimal PIFR. Having a high inspiratory flow may be a favorable trait in COPD.

Asthma and chronic obstructive pulmonary disease are chronic respiratory disorders characterized by airways obstruction and chronic inflammation. Exacerbations lead to worsening of symptoms and increased airflow obstruction in both airways diseases, and they are associated with increase in local and systemic inflammation. Exosomes are cell-derived membrane vesicles containing proteins, lipids, and nucleic acids that reflect their cellular origin. Through the transfer of these molecules, exosomes act as mediators of intercellular communication. Via selective delivery of their contents to target cells, exosomes have been proved to be involved in regulation of immunity and inflammation. Although, exosomes have been extensively investigated in different diseases, little is currently known about their role in asthma and COPD pathogenesis, and particularly in exacerbations. This review aims to systemically assess the potential role of exosomes in asthma and COPD exacerbations.

Background: Disorders of mucociliary clearance, such as cystic fibrosis (CF), primary ciliary dyskinesia (PCD) and bronchiectasis of unknown origin, are characterised by periods with increased respiratory symptoms, referred to as pulmonary exacerbations. These exacerbations are hard to predict and associated with lung function decline and the loss of quality of life. To optimise treatment and preserve lung function, there is a need for non-invasive and reliable methods of detection. Breath analysis might be such a method. Methods: We systematically reviewed the existing literature on breath analysis to detect pulmonary exacerbations in mucociliary clearance disorders. Extracted data included the study design, technique of measurement, definition of an exacerbation, identified compounds and diagnostic accuracy. Results: Out of 244 identified articles, 18 were included in the review. All studies included patients with CF and two also with PCD. Age and the definition of exacerbation differed between the studies. There were five that measured volatile organic compounds (VOCs) in exhaled breath using gas chromatography with mass spectrometry, two using an electronic nose and eleven measured organic compounds in exhaled breath condensate. Most studies showed a significant correlation between pulmonary exacerbations and one or multiple compounds, mainly hydrocarbons and cytokines, but the validation of these results in other studies was lacking. Conclusions: The detection of pulmonary exacerbations by the analysis of compounds in exhaled breath seems possible but is not near clinical application due to major differences in results, study design and the definition of an exacerbation. There is a need for larger studies, with a longitudinal design, international accepted definition of an exacerbation and validation of the results in independent cohorts.

Cystic fibrosis (CF) is a disease characterized by long-term and troublesome symptoms that affect the patient\'s life. This study aimed to assess and compare the health-related quality of life (HRQoL) of Polish CF patients and identify factors influencing it. The study group consisted of 79 patients (6 to 42 years old), who filled in an age-appropriate Cystic Fibrosis Questionnaire-Revised. Medical data were collected from each patient\'s medical records. The domains with the highest HRQoL median were eating problems (88.89), digestive symptoms (77.78) and physical functioning (75.00). The lowest-rated domain was social functioning (61.90). Age negatively correlated with eight domains, and most strongly with treatment burden (rho = -0.474). Physical functioning positively correlated with all spirometry parameters, and most strongly with FEV1% (rho = 0.588). Treatment burden, body image and respiratory symptoms were positively correlated with all spirometry parameters except PEF%. Present exacerbations reduced scores in almost all domains, and in the MANCOVA model they were a significant factor differentiating patients\' HRQoL. The univariate analysis of MANCOVA showed the significant effects of both health condition (F = 8.32, p = 0.005) and the COVID-19 pandemic (F = 5.89, p = 0.018) on social functioning domain, and of the place of residence on body image (F = 5.60, p = 0.21). A decreasing HRQoL with increasing age and during exacerbations indicates that it is important to focus on these aspects of patients\' lives and ensure they received the necessary support from their healthcare providers.