Yasutaka Nakano

A 75‐year‐old man with chronic obstructive pulmonary disease underwent endobronchial valve (EBV) placement in the left lower lobe and expectorated the valve from left B10 1 month later. Retrospective analysis of preprocedural dynamic computed tomography (CT) images showed that the median B10 luminal diameter increased from 4.25 mm at end‐expiration to 6.55 mm at end‐inspiration, approaching the upper limit of the recommended working range (4.0–7.0 mm) for the initially placed size 4.0 valve. A size 5.5 valve was subsequently placed without further expectoration. Bronchoscopic sizing under general anaesthesia with neuromuscular blockade and positive‐pressure ventilation may underestimate the maximum airway calibre encountered during spontaneous breathing, particularly in dependent bronchi. Inspiratory CT‐based airway assessment may provide useful complementary information for planning EBV placement and selecting an appropriate valve size.

Purpose: Respiratory muscle strength tests are commonly used in respiratory rehabilitation as an indicator of training in patients with chronic obstructive pulmonary disease (COPD). Although respiratory muscle strength tests are associated with lung function, their relationship with imaging parameters has not been fully investigated. Therefore, we aimed to reveal the relationship between imaging parameters and respiratory muscle strength and determine the usefulness of respiratory muscle strength tests as an indicator of the pathophysiology of dynamic pulmonary hyperinflation in smokers. Patients and Methods: In this single-center prospective observational study conducted in Japan, 48 patients with COPD and 10 non-COPD smokers were included in the final analysis. Most of the participants were men and the median age was 77 [interquartile range 70.8– 80.1]. Respiratory muscle strength tests, pulmonary function tests, and inspiratory and expiratory chest computed tomography were performed. Quantitative imaging parameters of gas trapping and emphysema were measured using the disease probability measure (DPM), a voxel-wise image analysis. Results: Maximal inspiratory and expiratory pressures (PImax and PEmax) were negatively correlated with residual volume/total lung capacity (Spearman’s rank correlation coefficient (r): − 0.37, − 0.40, respectively and p-value (p): < 0.01), but not with forced expiratory volume in 1 s. PImax and PEmax were negatively correlated with gas-trapping lesions recognized by DPM (DPM_GasTrap) in the single correlation analysis (r: − 0.31, − 0.37 and p: < 0.05, < 0.01, respectively), and the values for DPM_GasTrap significantly differed between the high and low PImax and PEmax groups. Conclusion: Respiratory muscle strength reflects the degree of gas trapping, not the degree of obstructive airflow limitation in smokers. It proves particularly valuable, especially during the initial phases of COPD, before emphysematous changes manifest.

Allergic bronchopulmonary aspergillosis is characterized by hypersensitivity to Aspergillus spp. and often causes intractable asthma. Studies have been conducted on biologics administered to patients with allergic bronchopulmonary aspergillosis; however, treatment may not always be successful. This may be due to the limitations of the current biologics that selectively target a single cytokine. Tezepelumab, a human monoclonal antibody that blocks the activity of thymic stromal lymphopoietin, broadly suppresses type 2 inflammation by regulating the upstream cascade of airway inflammation. Therefore, it is expected to have favorable effects in patients with allergic bronchopulmonary aspergillosis. We report three cases of allergic bronchopulmonary aspergillosis with uncontrolled symptoms despite the maximal use of conventional anti-asthmatic drugs such as inhalative agents, anti-leukotriene receptor antagonists, and antifungal drugs. None of the patients had previously received biologics. The addition of tezepelumab produced a marked clinical response in all three patients, which included fewer exacerbations and a reduced dosage of oral systemic corticosteroids and/or reduced as-needed short-acting beta-2 agonists. The patients’ pulmonary symptoms were better controlled, peripheral blood eosinophil counts and immunoglobulin E levels decreased, and quality of life scores and respiratory function parameters improved. Mucous plugs accompanied by atelectasis and infiltrative shadows observed on chest computed tomography also improved. Tezepelumab may be a promising treatment option for allergic bronchopulmonary aspergillosis in patients with severe asthma, offering effective symptom control and enabling reduction in systemic corticosteroid use.

Purpose: Regular exercise significantly influences chronic obstructive pulmonary disease (COPD) outcomes. However, the associations of exercise habits during adolescence compared to current exercise habits on physical activity (PA), body composition, pulmonary function, and CT imaging parameters remain unclear. Therefore, the present study aimed to clarify the associations of adolescent and current exercise habits with current conditions. Patients and Methods: This cross-sectional study enrolled 86 participants, including 72 with COPD and 14 with pre-COPD. Adolescent exercise habits were defined as regular exercise during ages 16 to 22 years, while current exercise habits were defined as regular exercise for at least 1 year. PA was assessed using a triaxial accelerometer, body composition was assessed using bioelectrical impedance analysis, and pulmonary function was assessed using spirometry and computed tomography. Results: Adolescent exercise habits were not significantly associated with PA or body composition, although they were associated with an increased lung volume. Compared to adolescent exercise habits, current exercise habits were associated with an increased duration of active engagement, less sedentary behavior, and increased diffusing capacity. Moreover, current exercise habits were associated with increased fat-free mass index, bone mineral content, and phase angle, which is an indicator of muscle quality. The influence of current exercise habits on these musculoskeletal indicators remained significant even after adjusting for age, sex, disease severity, and adolescent exercise habits. In addition, the relationship between PA and musculoskeletal health was more pronounced in patients with moderate-to-severe COPD than in those with mild COPD. Conclusion: Exercise during adolescence may promote increased lung volume. However, even after the onset of COPD, especially if the disease has progressed, regular exercise routines can help maintain PA, better body composition, and pulmonary function.

Background: Altered gut microbiota may contribute to COPD development or progression. Herein, we investigated the association of gut microorganisms with COPD, taking into account the impact of smoking status.Methods: This cross-sectional observational study was a part of the Shiga Epidemiological Study of Subclinical Atherosclerosis, a population-based cohort study of Japanese men aged 46–76 years, conducted from 2010 to 2016. The gut microbiome, determined using 16S rRNA gene sequencing, was compared among 99 never-smokers, 306 non-COPD ever-smokers and 76 patients with COPD while adjusting for age, body mass index, ethanol consumption and treatment for type 2 diabetes mellitus.Results: The abundance of phylum Firmicutes was comparable between patients with COPD and non-COPD ever-smokers but tended to be higher in never-smokers. Similarly, the α- and β-diversity analysis showed similarity between patients with COPD and non-COPD ever-smokers, which tended to differ from never-smokers. Discriminant analysis identified the genus[Prevotella]to be more prevalent in patients with COPD than in never-smokers or non-COPD ever-smokers.Post hocanalysis confirmed similarity of gut microbiome between COPD Global Initiative for Chronic Obstructive Lung Disease (GOLD) I and non-COPD ever-smokers, which was different from GOLD II.Conclusion: Smoking may alter the overall gut microbial composition, but gut microbial composition itself may not play a role in the development of COPD. Rather, specific gut bacteria, such as[Prevotella], could be a risk factor for the development of COPD; this may be a potential therapeutic target.

Purpose: Disease probability measure (DPM) is a useful voxel-wise imaging assessment of gas-trapping and emphysematous lesions in patients with chronic obstructive pulmonary disease (COPD). To elucidate the progression of COPD, we performed a cluster analysis using the following DPM parameters: normal (DPM_Normal), gas-trapping (DPM_GasTrap), and emphysematous lesions (DPM_Emph). Our findings revealed the characteristics of each cluster and the 3-year disease progression using imaging parameters. Patients and Methods: Inspiratory and expiratory chest computed tomography (CT) images of 131 patients with COPD were examined, of which 84 were followed up for 3 years. The percentage of low attenuation volume (LAV%) and the square root of the wall area of a hypothetical airway with an internal perimeter of 10 mm (√Aaw at Pi10) were quantitatively measured using inspiratory chest CT. A hierarchical cluster analysis was performed using the DPM parameters at baseline. Five clusters were named according to the dominant DPM parameters: normal (NL), normal-GasTrap (NL-GT), GasTrap (GT), GasTrap-Emphysema (GT-EM), and Emphysema (EM). Results: Women were predominantly diagnosed with GT. Forced expiratory volume in 1 s gradually decreased in the following order: NL, NL-GT, GT, GT-EM, and EM. DPM_Emph correlated well with LAV%. Four clusters other than NL showed significantly higher values of √Aaw at Pi10 than NL; however, no significant differences were observed among them. In all clusters, DPM_Emph increased after 3 years. DPM_Normal only increased in the GT cluster. Conclusion: Clusters using DPM parameters may reflect the characteristics of COPD and help understand the pathophysiology of the disease.