Prevalence and causes of chronic cough in Japan

BACKGROUND

Chronic cough is one of the most common symptoms of respiratory diseases and can adversely affect patients' quality of life and interfere with social activities, resulting in a significant social burden. A survey is required to elucidate the frequency and treatment effect of chronic cough. However, clinical studies that cover all of Japan have not yet been conducted.

METHODS

Patients who presented with a cough that lasted longer than 8 weeks and visited the respiratory clinics or hospitals affiliated with the Japan Cough Society during the 2-year study period were registered.

RESULTS

A total of 379 patients were enrolled, and those who did not meet the definition of chronic cough were excluded. A total of 334 patients were analyzed: 201 patients had a single cause, and 113 patients had two or more causes. The main causative diseases were cough variant asthma in 92 patients, sinobronchial syndrome (SBS) in 36 patients, atopic cough in 31 patients, and gastroesophageal reflux (GER)-associated cough in 10 patients. The time required to treat undiagnosed patients and those with SBS was significantly longer and the treatment success rate for GER-associated cough was considerably poor.

CONCLUSIONS

We confirmed that the main causes of chronic cough were cough variant asthma, SBS, atopic cough, and their complications. We also showed that complicated GER-associated cough was more likely to become refractory. This is the first nationwide study in Japan of the causes and treatment effects of chronic cough.

Incidence, etiology, and outcome of hospital-acquired pneumonia in patients with acute exacerbation of fibrotic idiopathic interstitial pneumonia

BACKGROUND

Acute exacerbations (AEs) of fibrotic idiopathic interstitial pneumonia (fIIP) that require hospitalization occur in some patients. During hospitalization, these patients can develop hospital-acquired pneumonia (HAP), a common hospital-acquired infection with a high mortality rate. However, the characteristics of HAP in AE-fIIP remain unknown. The purpose of this study was to determine the incidence, causative pathogens, and outcomes of HAP in patients with AE-fIIP.

METHODS

The medical records of consecutive patients who were hospitalized with AE-fIIP from January 2008 to December 2019 were analyzed for the incidence, causative pathogen, and survival of HAP. The records of patients with an obvious infection-triggered AE were excluded from analysis.

RESULTS

There were 128 patients with AE-fIIP (89 with idiopathic pulmonary fibrosis [IPF] and 39 with non-IPF fIIP) who were hospitalized a total of 155 times (111 with IPF and 44 with non-IPF fIIP). HAP occurred in 49 patients (40 with IPF and 9 with non-IPF fIIP). The incidence and the in-hospital mortality rates of HAP in patients with AE-fIIP were high, at 32.2% and 48.9%, respectively. Corynebacterium spp. was the most common causative pathogen, which was followed by human cytomegalovirus (HCMV).

CONCLUSIONS

The incidence and the in-hospital mortality rates of HAP in patients with AE-fIIP are high. To improve their survival, patients with fIIP who had AEs and HAP should receive prompt empirical treatment for possible infections with Corynebacterium spp. and testing for HCMV.

Modeling future cliff-front waves during sea level rise and implications for coastal cliff retreat rates

It is often assumed that future coastal cliff retreat rates will accelerate as global sea level rises, but few studies have investigated how SLR (sea level rise) might change cliff-front wave dynamics. Using a new simple numerical model, this study simulates the number and type (breaking, broken, or unbroken) of cliff-front waves under future SLR scenarios. Previous research shows breaking waves deliver more energy to cliffs than broken waves, and unbroken waves generate minimal impact. Here, we investigated six cliff-platform profiles from three regions (USA, New Zealand, and UK) with varied tidal ranges and wave climates. Model inputs included 2013-2100 hindcast/forecast incident wave height and tidal water level, and three future SLR scenarios. Results show the number of both cliff-front breaking and broken waves generally increase for a high-elevation (relative to tide) cliff-platform junction. In contrast, breaking/broken wave occurrence decrease by 38-92% for a near-horizontal shore platform with a low-elevation cliff-platform junction under a high SRL scenario, leading to high (96-97%) unbroken wave occurrence. Overall, results suggest the response of cliff-front waves to future SLR is complex and depends on shore platform geometries and SLR scenarios, indicating that future cliff retreat rates may not homogeneously accelerate under SLR.

Increased blood eosinophils and airflow obstruction as new-onset asthma predictors in the elderly: The Nagahama study

BACKGROUND

Asthma in the elderly needs more attention in an aging society. However, it is likely to remain underdiagnosed and undertreated. This study aimed to clarify clinical characteristics of new-onset asthma in the elderly, describing the prevalence, predictive factors, and comorbidities after asthma diagnosis of new-onset asthma in the elderly in the general population.

METHODS

This community-based prospective cohort study enrolled 9804 generally healthy participants (30-74 years old) in Nagahama City, and conducted a follow-up assessment after 5 years. Elderly participants were those aged ≥65 years at baseline. Patients with new-onset asthma were defined as participants without asthma at baseline assessment and with asthma at the follow-up assessment.

RESULTS

Among the 7948 participants analyzed in this study, 28 (1.4%) elderly and 130 (2.2%) non-elderly had new-onset asthma. Multiple logistic regression analysis revealed low forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC) and high blood eosinophil counts at baseline as predicting factors for new-onset asthma in the elderly. Additionally, subsequent incidence of new-onset asthma was higher in elderly participants with both predictors (high blood eosinophil counts and low FEV1/FVC at baseline) than those with none or one of the predictors before asthma diagnosis. Lastly, elderly patients with new-onset asthma had more frequent comorbidity of moderate to severe sleep disordered breathing than those non-elderly.

CONCLUSIONS

Eosinophilic inflammation and airflow obstruction may predict subsequent new-onset asthma after the age of 65 years. Revealing the characteristics of new-onset asthma in the elderly can aid in the prevention of underdiagnosed asthma.

Role of bronchial hyperresponsiveness in patients with obstructive sleep apnea with asthma-like symptoms

BACKGROUND

Obstructive sleep apnea (OSA) is one of the major co-morbidities and aggravating factors of asthma. In OSA-complicated asthma, obesity, visceral fat, and systemic inflammation are associated with its severity, but the role of bronchial hyperresponsiveness (BHR) is unclear. We investigated the involvement of BHR and mediastinal fat width, as a measure of visceral fat, with OSA severity in patients with OSA and asthma-like symptoms.

METHODS

Patients with OSA who underwent BHR test and chest computed tomography scan for asthma-like symptoms were retrospectively enrolled. We evaluated the relationship between apnea-hypopnea index (AHI) and PC20 or anterior mediastinal fat width, stratified by the presence or absence of BHR.

RESULTS

OSA patients with BHR (n = 29) showed more obstructive airways and frequent low arousal threshold and lower mediastinal fat width, and tended to show fewer AHI than those without BHR (n = 25). In the overall analysis, mediastinal fat width was significantly positively correlated with AHI, which was significant even after adjustment with age and gender. This was especially significant in patients without BHR, while in OSA patients with BHR, there were significant negative associations between apnea index and airflow limitation, and hypopnea index and PC20.

CONCLUSIONS

Risk factors for greater AHI differed depending on the presence or absence of BHR in OSA patients with asthma-like symptoms. In the presence of BHR, severity of asthma may determine the severity of concomitant OSA.

Evaluation of patients with chronic obstructive pulmonary disease by maximal inspiratory pressure and diaphragmatic excursion with ultrasound sonography

BACKGROUND

Decreased respiratory muscle strength and muscle mass is key in diagnosing respiratory sarcopenia. However, the role of reduced diaphragm activity, expressed as the maximal level of diaphragmatic excursion (DEmax), in diagnosing respiratory sarcopenia in patients with chronic obstructive pulmonary disease (COPD) remains unclear. This study aimed to characterize patients with COPD and low DEmax and maximal inspiratory pressure (MIP), a measure of inspiratory muscle strength, and assess the role of DEmax in respiratory sarcopenia.

METHODS

Patients with COPD underwent spirometry, exercise tolerance (VO2peak) test, and MIP measurement. DEmax and sternocleidomastoid thickness at the maximal inspiratory level (TscmMIL) were assessed using ultrasound sonography.

RESULTS

Overall, 58 patients with COPD (median age, 76 years; median %FEV1, 51.3 %) were included, 28 of whom showed a %MIP of ≥80 %, defined as having preserved MIP. Based on the %MIP of 80 % and median value of DEmax (48.0 mm) as thresholds, the patients were stratified into four groups: both-high (n = 18), %MIP-alone low (n = 11), DEmax-alone low (n = 10), and both-low (n = 19) groups. The both-low group exhibited the lowest %FEV1, Δinspiratory capacity, VO2peak, and TscmMIL, and these values were significantly lower than those of the both-high group. Except for %FEV1, these values were significantly lower in the both-low group than in the %MIP-alone low group despite adjusting DEmax level for body mass index.

CONCLUSION

Measuring DEmax along with MIP can characterize patients with COPD, reduced exercise capacity, and decreased accessory respiratory muscle mass and can help diagnose respiratory sarcopenia.

Associations of fractional exhaled nitric oxide with airway dimension and mucus plugs on ultra-high-resolution computed tomography in former smokers and nonsmokers with asthma

BACKGROUND

Associations of fractional exhaled nitric oxide (FeNO) with airway wall remodeling and mucus plugs remain to be explored in smokers and nonsmokers with asthma. Ultra-high-resolution computed tomography (U-HRCT), which allows accurate structural quantification of airways >1 mm in diameter, was used in this study to examine whether higher FeNO was associated with thicker walls of the 3rd to 6th generation airways and mucus plugging in patients with asthma.

METHODS

The retrospective analyses included consecutive former smokers and nonsmokers with asthma who underwent U-HRCT in a hospital. The ratio of wall area to summed lumen and wall area was calculated as the wall area percent (WA%). Mucus plugging was visually scored.

RESULTS

Ninety-seven patients with asthma (including 59 former smokers) were classified into low (<20 ppb), middle (20-35 ppb), and high (>35 ppb) FeNO groups (n = 24, 26, and 47). In analysis including all patients and subanalysis including nonsmokers or former smokers, WA% in the 6th generation airways was consistently higher in the high FeNO group than in the low FeNO group, whereas WA% in the 3rd to 5th generation airways was not. In multivariable models, WA% in the 6th generation airways and the rate of mucus plugging were higher in the high FeNO group than in the low FeNO group after adjusting for age, sex, body mass index, smoking status, lung volume, and allergic rhinitis presence.

CONCLUSIONS

Higher FeNO may reflect the inflammation and remodeling of relatively peripheral airways in asthma in both former smokers and nonsmokers.

Sputum microbiota and inflammatory subtypes in asthma, COPD, and its overlap

Background

Airway microbiota in asthma-chronic obstructive pulmonary disease (COPD) overlap (ACO) remains unknown.

Objective

This study with ACO-enriched population aimed to clarify airway microbiota in ACO and in mixed granulocytic inflammation, often detected in ACO and chronic airway diseases.

Methods

This is an observational cross-sectional study. Patients with asthma with airflow limitation, ACO, and COPD were enrolled. Blood tests, pulmonary function, exhaled nitric oxide, and sputum tests were conducted. Sputum microbiota was evaluated using the 16S rRNA gene sequencing technique.

Results

A total of 112 patients (13 asthma, 67 ACO, and 32 COPD) were examined. There were no significant differences in α-diversity among the 3 diseases. The relative abundances of phylum Bacteroidetes, class Bacteroidia, and genus Porphyromonas were associated with decreased eosinophilic inflammation, and were significantly lower in ACO than in COPD. In a comparison of sputum inflammatory subtypes, the proportion of Haemophilus was numerically highest in the mixed granulocytic subtype, followed by the neutrophilic subtype. Likewise, the proportion of Haemophilus was the highest in the intermediate-high (2%-8%) sputum eosinophil group and lowest in the severe (≥8%) eosinophil group. Clinically, Haemophilus proportion was associated with sputum symptoms. Finally, the proportion of Streptococcus was associated with higher blood eosinophil counts and most severe airflow limitation.

Conclusions

Bacteroidia and Porphyromonas abundances in sputum are associated with the eosinophil-low phenotype, and ACO may be characterized by a decrease in these taxa. A mild elevation in sputum eosinophil does not preclude the presence of Haemophilus, which should be noted in the management of obstructive airway diseases.

Evaluation of elevated plasma fatty acids as relevant factors for adult-onset asthma: The Nagahama Study

BACKGROUND

Obesity and increased body mass index (BMI) are the known risk factors for adult-onset asthma. Serum free fatty acid (FFA) and other blood lipid levels are generally elevated in patients with obesity and may be involved in the onset of asthma. However, it remains largely unknown. This study aimed to elucidate the relationship between plasma fatty acids and new-onset asthma.

METHODS

This community-based Nagahama Study in Japan enrolled 9804 residents. We conducted self-reporting questionnaires, lung function tests, and blood tests at baseline and 5 years later as follow-up. At the follow-up, plasma fatty acids were measured using gas chromatography-mass spectrometry. Body composition analysis was also measured at the follow-up. The associations between fatty acids and new-onset asthma were evaluated using a multifaceted approach, including targeted partial least squares discriminant analysis (PLS-DA).

RESULTS

In PLS-DA for new-onset asthma, palmitoleic acid was identified as the fatty acid most associated with asthma onset. In the multivariable analysis, higher levels of FFA, palmitoleic acid, or oleic acid were significantly associated with new-onset asthma, independent of other confounding factors. The high body fat percentage itself was not the relevant factor, but showed a positive interaction with plasma palmitoleic acid for new-onset asthma. When stratified by gender, the impacts of higher levels of FFA or palmitoleic acid on new-onset asthma remained significant in females, but not in males.

CONCLUSIONS

Elevated levels of plasma fatty acids, particularly palmitoleic acid, may be a relevant factor for new-onset asthma.

Clinical characteristics of allergic bronchopulmonary mycosis caused by Schizophyllum commune

BACKGROUND

Allergic bronchopulmonary mycosis (ABPM) is an allergic disease caused by type I and type III hypersensitivity to environmental fungi. Schizophyllum commune, a basidiomycete fungus, is one of the most common fungi that causes non-Aspergillus ABPM.

OBJECTIVE

Herein, we attempted to clarify the clinical characteristics of ABPM caused by S. commune (ABPM-Sc) compared with those of allergic bronchopulmonary aspergillosis (ABPA).

METHODS

Patients with ABPM-Sc or ABPA were recruited from a nationwide survey in Japan, a multicenter cohort, and a fungal database at the Medical Mycology Research Center of Chiba University. The definition of culture-positive ABPM-Sc/ABPA is as follows: (1) fulfills five or more of the 10 diagnostic criteria for ABPM proposed by Asano et al., and (2) positive culture of S. commune/Aspergillus spp. in sputum, bronchial lavage fluid, or mucus plugs in the bronchi.

RESULTS

Thirty patients with ABPM-Sc and 46 with ABPA were recruited. Patients with ABPM-Sc exhibited less severe asthma and presented with better pulmonary function than those with ABPA (p = 0.008-0.03). Central bronchiectasis was more common in ABPM-Sc than that in ABPA, whereas peripheral lung lesions, including infiltrates/ground-glass opacities or fibrotic/cystic changes, were less frequent in ABPM-Sc. Aspergillus fumigatus-specific immunoglobulin (Ig)E was negative in 10 patients (34%) with ABPM-Sc, who demonstrated a lower prevalence of asthma and levels of total serum IgE than those with ABPM-Sc positive for A. fumigatus-specific IgE or ABPA.

CONCLUSIONS

Clinical characteristics of ABPM-Sc, especially those negative for A. fumigatus-specific IgE, differed from those of ABPA.

Significance of Self-Injectable Biologics in Japanese Patients with Severe Allergic Diseases: Focusing on Pen-Type Devices and Copayment

Patients and Methods

A questionnaire survey was administered to 18, 14, and 3 patients introduced to home self-injection of dupilumab or mepolizumab using a pen-type device for atopic dermatitis, asthma alone, and asthma plus chronic rhinosinusitis with nasal polyps, respectively.

Results

All but one participant wished to continue self-injection. Most participants affirmed the reduction in copayment (88.6%) and saving time and labor for hospital visits (88.6%). Six patients who received dupilumab complained of side effects, but all, except for one, continued the treatment. Of the 13 patients who had previously used a syringe-type device, 10 preferred the pen type because of its ease of use, while 3 (23%) preferred the syringe type because of the self-adjustable injection speed for pain control.

Conclusion

Administration of biologics using pen-type devices is easier, and the introduction of home self-injection leads to a reduction in outpatient visits and copayment.

Longitudinal Changes and Association of Respiratory Symptoms with Preserved Ratio Impaired Spirometry (PRISm): The Nagahama Study

Rationale: Subjects with preserved ratio impaired spirometry (PRISm) experience increased respiratory symptoms, although they present heterogeneous characteristics. However, the longitudinal changes in these symptoms and respiratory function are not well known. Objectives: To investigate PRISm from the viewpoint of respiratory symptoms in a longitudinal, large-scale general population study. Methods: The Nagahama study included 9,789 inhabitants, and a follow-up evaluation was conducted after 5 years. Spirometry and self-administered questionnaires regarding respiratory symptoms, including prolonged cough, sputum and dyspnea, and comorbidities were conducted. Results: In total, 9,760 subjects were analyzed, and 438 subjects had PRISm. Among the subjects with PRISm, 53% presented with respiratory symptoms; dyspnea was independently associated with PRISm. Follow-up assessment revealed that 73% of the subjects with PRISm with respiratory symptoms were consistently symptomatic, whereas 39% of the asymptomatic subjects with PRISm developed respiratory symptoms within 5 years. In addition, among subjects with respiratory symptoms without airflow limitation at baseline, PRISm was a risk factor for the development of airflow limitation independent of smoking history and comorbidities. Conclusions: This study demonstrated that 53% of the subjects with PRISm had respiratory symptoms; dyspnea was a distinct characteristic of PRISm. Approximately three-fourths of the symptomatic subjects with PRISm consistently complained of respiratory symptoms within 5 years. Together with our result that PRISm itself is an independent risk factor for the development of chronic obstructive pulmonary disease among subjects with respiratory symptoms, the clinical course of subjects with PRISm with symptoms requires careful monitoring.

Association between blood eosinophil count and small airway eosinophils in smokers with and without COPD

Introduction

Airway eosinophilic inflammation is a pathological feature in a subgroup of patients with COPD and in some smokers with a high COPD risk. Although blood eosinophil count is used to define eosinophilic COPD, the association between blood eosinophil count and airway eosinophilic inflammation remains controversial. This cross-sectional study tested this association in smokers with and without COPD while considering potential confounders, such as smoking status and comorbidities.

Methods

Lung specimens were obtained from smokers with and without COPD and non-COPD never-smokers undergoing lung lobectomy. Those with any asthma history were excluded. The infiltration of eosinophils into the small airway wall was quantified on histological sections stained with major basic protein (MBP).

Results

The number of airway MBP-positive cells was greater in smokers (n=60) than in never-smokers (n=14). Smokers with and without COPD (n=30 each) exhibited significant associations between blood eosinophil count and airway MBP-positive cells (ρ=0.45 and 0.71). When smokers were divided into the high and low airway MBP groups based on their median value, blood eosinophil count was higher in the high-MBP group, with no difference in age, smoking status, comorbidities, emphysema or coronary artery calcification on computed tomography, and inhaled corticosteroid (ICS) use. The association between greater blood eosinophil count and the high-MBP group was confirmed in multivariable models adjusted for smoking status, airflow limitation and ICS use.

Conclusion

The blood eosinophil count may reflect eosinophilic inflammation in the small airways in smokers with and without COPD.

Association of lower plasma citric acid with prolonged cough: the Nagahama study

Little is known about the association of prolonged cough, a common and troublesome symptom, with metabolic pathways. We aimed to clarify this association using data from the Nagahama cohort, a prospective study of participants from the general population. Self-report questionnaires on prolonged cough were collected at baseline and 5-year follow-up assessments. Blood tests at follow-up were used for gas chromatography-mass spectrometry-based metabolomics. The association between metabolites and prolonged cough was examined using the partial least squares discriminant analysis and multiple regression analysis. Among the 7432 participants, 632 had newly developed prolonged cough at follow-up, which was defined as "new-onset prolonged cough". Low plasma citric acid was significantly associated with new-onset prolonged cough, even after the adjustment of confounding factors including the presence of asthma, upper airway cough syndrome (UACS), and gastroesophageal reflux disease (GERD). A similar association was observed for isocitric acid, 3-hydroxybutyric acid, and 3-hydroxyisobutyric acid. The analysis of these four metabolites revealed that citric acid had the strongest association with new-onset prolonged cough. This significant association remained even when the analysis was confined to participants with UACS or GERD at baseline or follow-up, and these associations were also observed in participants (n = 976) who had prolonged cough at follow-up regardless of baseline status. In conclusion, low blood citric acid may be associated with prolonged cough.

Diaphragm dome height on chest radiography as a predictor of dynamic lung hyperinflation in COPD

Background and objective

Dynamic lung hyperinflation (DLH) can play a central role in exertional dyspnoea in patients with COPD. Chest radiography is the basic tool for assessing static lung hyperinflation in COPD. However, the predictive capacity of DLH using chest radiography remains unknown. This study was conducted to determine whether DLH can be predicted by measuring the height of the right diaphragm (dome height) on chest radiography.

Methods

This single-centre, retrospective cohort study included patients with stable COPD with pulmonary function test, cardiopulmonary exercise test, constant load test and pulmonary images. They were divided into two groups according to the median of changes of inspiratory capacity (ΔIC=IC lowest - IC at rest). The right diaphragm dome height and lung height were measured on plain chest radiography.

Results

Of the 48 patients included, 24 were classified as having higher DLH (ΔIC ≤-0.59 L from rest; -0.59 L, median of all) and 24 as having lower DLH. Dome height correlated with ΔIC (r=0.66, p<0.001). Multivariate analysis revealed that dome height was associated with higher DLH independent of % low attenuation area on chest computed tomography and forced expiratory volume in 1 s (FEV₁) % predicted. Furthermore, the area under the receiver operating characteristic curve of dome height to predict higher DLH was 0.86, with sensitivity and specificity of 83% and 75%, respectively, at a cut-off of 20.5 mm. Lung height was unrelated to ΔIC.

Conclusion

Diaphragm dome height on chest radiography may adequately predict higher DLH in patients with COPD.

Prognostic value of the qSOFA in patients with acute exacerbation of idiopathic pulmonary fibrosis

BACKGROUND

Patients with idiopathic pulmonary fibrosis (IPF) have a slowly progressive clinical course, although some develop acute exacerbations (AEs). An easily obtained composite score is desirable for predicting the survival rate in patients with AE of IPF (AE-IPF). We investigated the quick sequential organ failure assessment (qSOFA), originally developed to identify sepsis, as a predictor of mortality in patients with AE-IPF and compared it to other composite assessments.

METHODS

Consecutive patients with IPF admitted for their first AE between 2008 and 2019 were recruited retrospectively. The association between the qSOFA score obtained at admission and mortality was investigated.

RESULTS

During the study period, 97 patients with AE-IPF were hospitalized. The hospital mortality was 30.9%. Multivariate logistic regression analysis revealed that both the qSOFA and the Japanese Association for Acute Medicine (JAAM)-disseminated intravascular coagulation (DIC) scores were significant predictors of hospital mortality (odds ratio [OR] 3.86, 95% confidence interval [CI] 1.43-10.3; p = 0.007 and OR 2.71, 95% CI 1.56-4.67; p = 0.0004; respectively). Kaplan-Meier survival curves showed that both scores were consistently associated with survival. Furthermore, the sum of the two scores was a more effective predictor than the individual scores.

CONCLUSIONS

The qSOFA score of patients admitted with AE-IPF was associated with both in-hospital and long-term mortality, which was also true for the JAAM-DIC score. The qSOFA score plus the JAAM-DIC score should be determined during the diagnostic evaluation of a patient with AE-IPF. Both scores combined may be more effective at predicting outcomes than individual scores.

Effectiveness of bronchial thermoplasty in patients with asthma exhibiting overweight/obesity and low quality of life

Bronchial thermoplasty (BT) is effective in some severe asthma patients; however, the specific asthma phenotypes that produce a good response to BT are not fully understood. Clinical data were retrospectively reviewed in severe asthma patients who underwent BT at a single institution in Japan. At the follow-up assessment, the Asthma Quality of Life Questionnaire (AQLQ) scores (P = 0.003), maintenance oral corticosteroid doses (P = 0.027), and exacerbation frequency (P = 0.017) were significantly improved, while prebronchodilator-forced expiratory volume in 1 second (% predicted) did not significantly change (P = 0.19). When we grouped the patients into 2 groups according to their body mass index levels, the AQLQ scores were more improved in patients with overweight/obesity than those with normal weight (P = 0.01). This study showed that patients with non-controlled severe asthma exhibiting overweight/obesity and low quality of life had potential benefits from BT.

Roles of Staphylococcus aureus and sensitization to staphylococcal enterotoxin in bronchiectasis

Staphylococcus aureus (S. aureus) is an inducer of mucosal type 2 immune response. To test the hypothesis that airway colonization with S. aureus may reflect allergic predisposition with staphylococcal enterotoxin (SE) sensitization in bronchiectasis, we retrospectively examined the association between SE sensitization and S. aureus and Pseudomonas aeruginosa (P. aeruginosa) in sputum of patients with bronchiectasis (n = 35). Overall, 14 (40%) patients with bronchiectasis were sensitized to either staphylococcal enterotoxin A (SEA) or staphylococcal enterotoxin B (SEB). SEA sensitization was more frequently observed in patients with sputum S. aureus than those without it. Patients with sputum S. aureus but without P. aeruginosa exhibited the highest SEA sensitization frequency and serum total IgE levels. Patients with both S. aureus and P. aeruginosa exhibited the highest blood eosinophils. In conclusion, S. aureus in the lower airway may indicate an allergic predisposition with SE sensitization and blood eosinophilia in bronchiectasis.

Relationships between dietary diversity and gut microbial diversity in the elderly

Diet is considered as a major driver of gut microbiota composition. However, little is known about the relationship between overall dietary balance and gut microbiota, especially in the elderly. Here, using the Quantitative Index for Dietary Diversity (QUANTIDD), we analysed the relationships between dietary diversity and gut microbiota diversity in 445 Japanese subjects aged 65-90 years. We also examined the effect of age by comparing the young-old group aged 65 to 74 years (<75 years group; n=246) and the old-old group aged 75 years and older (≥75 years group; n=199). QUANTIDD showed significant positive relationships with Pielou's evenness and Shannon indices, two α-diversity indices related to the uniformity of species distribution. This suggests that a more diverse diet is associated with a more uniform abundance of various bacterial groups, rather than a greater variety of gut bacteria. QUANTIDD also showed significant positive associations with the abundance of Anaerostipes, Eubacterium eligens group, and Eubacterium ventriosum group, which produce short-chain fatty acids (SCFAs) and are beneficial to health. Negative association was found with the abundance of Ruminococcus gnavus group, which produces inflammatory polysaccharides. Positive associations between QUANTIDD and α-diversity indices or the abundance of specific bacterial groups were identified among all subjects and in the <75 years group, but not in the ≥75 years group. Our results suggest that dietary diversity contributes to the diversity of the gut microbiota and increases the abundance of SCFAs-producing bacteria, but only up to a certain age. These findings help to understand the complex relationship between diet and gut microbiota, and provide hints for specific dietary interventions to promote beneficial gut microbiota in the elderly.

Development of airflow limitation, dyspnoea, and both in the general population: the Nagahama study

Subjects with subclinical respiratory dysfunction who do not meet the chronic obstructive pulmonary disease (COPD) criteria have attracted attention with regard to early COPD intervention. Our aim was to longitudinally investigate the risks for the development of airflow limitation (AFL) and dyspnoea, the main characteristics of COPD, in a large-scale community-based general population study. The Nagahama study included 9789 inhabitants, and a follow-up evaluation was conducted after 5 years. AFL was diagnosed using a fixed ratio (forced expiratory volume in one second (FEV₁)/forced vital capacity (FVC) < 0.7). We enrolled normal subjects aged 40-75 years with no AFL, dyspnoea or prior diagnosis of asthma or COPD at baseline. In total, 5865 subjects were analysed, 310 subjects had subclinical respiratory dysfunction (FEV₁/FVC < the lower limit of normal; n = 57, and FEV₁ < 80% of the predicted value (preserved ratio impaired spirometry); n = 256). A total of 5086 subjects attended the follow-up assessment, and 449 and 1021 subjects developed AFL and dyspnoea, respectively. Of these, 100 subjects developed AFL with dyspnoea. Baseline subclinical respiratory dysfunction was independently and significantly associated with AFL with dyspnoea development within 5 years. Subjects with subclinical respiratory dysfunction are at risk of developing COPD-like features and require careful monitoring.

Protein C activity as a potential prognostic factor for nursing home-acquired pneumonia

Introduction

Despite the poor prognosis for nursing home acquired pneumonia (NHAP), a useful prognostic factor is lacking. We evaluated protein C (PC) activity as a predictor of in-hospital death in patients with NHAP and community-acquired pneumonia (CAP).

Methods

This prospective, observational study included all patients hospitalized with pneumonia between July 2007 and December 2012 in a single hospital. We measured PC activity at admission and investigated whether it was different between survivors and non-survivors. We also examined whether PC activity < 55% was a predictor for in-hospital death of pneumonia by logistic regression analysis with CURB-65 items (confusion, blood urea >20 mg/dL, respiratory rate >30/min, and blood pressure <90/60 mmHg, age >65). When it was a useful prognostic factor for pneumonia, we combined PC activity with the existing prognostic scores, the pneumonia severity index (PSI) and CURB-65, and analyzed its additional effect by comparing the areas under the receiver operating characteristic curves (AUCs) of the modified and original scores.

Results

Participants comprised 75 NHAP and 315 CAP patients. PC activity was lower among non-survivors than among survivors in NHAP and all-pneumonia (CAP+NHAP). PC activity <55% was a useful prognostic predictor for NHAP (Odds ratio 7.39 (95% CI; 1.59–34.38), and when PSI or CURB-65 was combined with PC activity, the AUC improved (from 0.712 to 0.820 for PSI, and 0.657 to 0.734 for CURB-65).

Conclusions

PC activity was useful for predicting in-hospital death of pneumonia, especially in NHAP, and became more useful when combined with the PSI or CURB-65.

The vascular response to ultrathin biodegradable polymer sirolimus-eluting stent at 2-weeks and 1-year follow up in patients with ST-elevation myocardial infarction

Background

Recent clinical study suggests newer-generation drug-eluting stents (DES) that combine ultrathin strut and nano-coating with biodegradable polymers sirolimus-eluting stent (BP-SES) could improve long-term clinical outcomes in patients with ST-elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI) over current generation DES. However, the details of vascular response in very early and chronic phase have not been systematically addressed.

Objective and method

We exploratory investigate early and chronic vascular response following BP-SES implantation in patients with STEMI to reveal mechanism of the favorable clinical outcomes in recent studies using frequency domain-optical coherence tomography (FD-OCT).

Consecutive twenty-four patients with STEMI who underwent FD-OCT after primary PCI and were eligible for follow-up FD-OCT at 2 weeks and 1 year after implantation were enrolled between June 2018 and August 2020.

OCT was performed immediately after PCI, at 2-weeks (2W) and 1-year (1Y) after the primary PCI. Struts were recorded as uncovered if any part was visibly exposed in the lumen or covered if a layer of tissue covered all reflecting surfaces. Struts of stents that are smaller than 3.0mm of diameter with more than 80μm between the center reflection and the adjacent vessel surface were recorded as malapposed. The reduction of atherothrombotic protrusion burden within the stent was also assessed.

Results

Twenty-four patients (age 64.9±11.4 years, male 83.3%) were enrolled.

The percentage of uncovered struts significantly decreased from post-PCI to 2W follow-up and from 2W follow-up to 1Y follow-up (62±20% post-PCI versus 27±11% at 2W follow up, p&lt;0.0001 and 2W follow-up versus 3.3±3.3% at 1Y follow up, p&lt;0.0001). Malapposed struts also decreased from post-PCI to 2W follow-up (4.1±3.6% post-PCI versus 1.5±2.2% at 2W follow-up, p&lt;0.0001), but no significant difference was shown between 2W follow-up and 1Y follow-up (2W follow-up versus 1.0±2.3 at 1Y follow up, p=0.12). The average protrusion area of athero-thrombotic burden decreased (0.57±0.32 at post-PCI versus 0.42±0.22 mm2 at 2W follow up, p&lt;0.0001) and its volume showed similar tendency (16.6±10.7 at post-PCI versus 12.9±8.23 mm3 at 2W follow up, p=0.0011). Thrombus was shown in all patients at post-PCI, but two patients (8.0%) showed it at 1Y follow-up.

Conclusion(s)

This study elucidated very early and chronic vascular responses following ultrathin strut BP-SES implantation in STEMI patients by FD-OCT. It showed resolution of athero-thrombotic materials in very early phase and favorable progression of strut coverage in very early and chronic phase.

Funding Acknowledgement

Type of funding sources: None.

Usefulness of the synthesized 18-lead ECG in identify the origin of premature ventricular contractions

Background

There are have been reports on the 12-lead ECG waveforms used to identify ventricular premature contractions (VPCs), but there are not enough algorithms. On the other hand, the synthesized 18-lead ECG adds the right-side chest leads (V3R, V4R, and V5R) and back leads (V7, V8, and V9) to the 12-lead ECG.

Purpose

This aim of this study was to evaluate whether the waveforms of the 18-lead ECG are useful in predicting the origin of VPCs.

Methods

We studied 86 consecutive patients (age :61.8±16.0 years, male: 54.5%) enrolled from multicenter who underwent radiofrequency catheter ablation for VPCs. We retrospectively investigated the association between origin of the VPCs and characteristics of the synthetic 18-leads ECG.

Results

The 18-lead ECG showed a specific pattern for the VPC originating near the His-bundle. In 17 cases, the QRS morphology in V5R exhibited a QS pattern, and 13 of 17 cases had VPCs originating near the His-bundle. In the other 69 cases, V5R did not exhibit a QS pattern. ROC curve analysis showed that the QS pattern in V5R predicted VPC originating near the His-bundle with high accuracy: sensitivity 100.0%, specificity 94.5%, and AUC 0.98. Furthermore, the positive predictive value was 76.5% and negative predictive value 100.0%.

Conclusion

The QS pattern shown in V5R of the 18-lead ECG was a useful parameter for identifying VPCs originating near the His-bundle, which might be a good reference indicator during radiofrequency catheter ablation for VPCs.

Funding Acknowledgement

Type of funding sources: None.

Age-specific associations of early daycare, older siblings, severe airway infection, and preterm birth with subsequent atopic diseases

BACKGROUND

The effects of infection and developmental adaptations in infancy on the prevalence of subsequent atopy-related diseases at different ages during childhood are not fully determined. This study aims to examine the similarities and differences in the age-specific association of asthma, allergic rhinitis/conjunctivitis, and atopic dermatitis with early-life infection-related factors (i.e., daycare, older siblings, and severe airway infection) and developmental adaptations (i.e., preterm birth and rapid weight gain) in children.

METHODS

In this longitudinal cohort study (n = 47,015), children were followed from 0.5 to 11 years. The potential risks and protective factors, including daycare attendance at 0.5 years, existence of older siblings, history of hospitalization due to cold/bronchitis/bronchiolitis/pneumonia during 0.5-1.5 years, preterm birth, and rapid weight gain in the first 2.5 years, were assessed using multivariable logistic regression with adjustments for potential confounders.

RESULTS

A protective association was observed between early-life daycare attendance and asthma at 5.5-9 years, which disappeared after 10 years. A protective association was also noted throughout childhood between early daycare attendance and older siblings with allergic rhinitis/conjunctivitis. However, the association between early daycare and atopic dermatitis was found to be risky during childhood. In contrast, the early-life history of hospitalization owing to cold/bronchitis/bronchiolitis/pneumonia was identified to be a risk factor for developing both asthma and allergic rhinitis/conjunctivitis. Preterm birth was a significant risk factor for childhood asthma.

CONCLUSION

Different age-specific patterns were demonstrated in the relationship between early daycare, severe airway infection, preterm birth, and atopy-related diseases in childhood.

Pathophysiological relevance of sputum MUC5AC and MUC5B levels in patients with mild asthma

BACKGROUND

Airway mucus hypersecretion is an important pathophysiological feature of asthma. MUC5AC and MUC5B are the major secreted polymeric mucins in airways, and their compositions affect mucus properties. Despite the increasing appreciation of MUC5AC and MUC5B compositions in asthmatic airways, their pathophysiological relevance remains to be fully understood in humans.

METHODS

In this cross-sectional study, we prospectively enrolled newly referred steroid-untreated patients with mild asthma and healthy controls. We compared induced sputum MUC5AC and MUC5B levels between patients and controls. Subsequently, we assessed the correlation between MUC5AC and MUC5B levels and clinical indices in patients. Sputum MUC5AC and MUC5B levels were measured using enzyme-linked immunosorbent assays.

RESULTS

Sputum MUC5AC and MUC5B levels were significantly higher in patients (n = 87) than in controls (n = 22) (p = 0.0002 and p = 0.006, respectively). The ratio of sputum MUC5AC to MUC5B tended to be higher in patients than in controls (p = 0.07). Sputum MUC5AC levels significantly and positively correlated with fractional exhaled nitric oxide at expiratory flow of 50 mL/s (Spearman's rho = 0.29, p = 0.006), sputum eosinophil proportion (rho = 0.34, p = 0.0013), and airway sensitivity (rho = 0.39, p = 0.0005). By contrast, sputum MUC5B levels significantly and positively correlated with airway sensitivity (rho = 0.35, p = 0.002) and negatively correlated with airway reactivity (rho = -0.33, p = 0.004).

CONCLUSIONS

Sputum MUC5AC is increased by protein levels and involved in airway type 2/eosinophilic inflammation and airway hyperresponsiveness in steroid-untreated patients with mild asthma.

Nationwide survey of refractory asthma with bronchiectasis by inflammatory subtypes

RATIONALE

Bronchiectasis and bronchiolitis are differential diagnoses of asthma; moreover, they are factors associated with worse asthma control.

OBJECTIVE

We determined clinical courses of bronchiectasis/bronchiolitis-complicated asthma by inflammatory subtypes as well as factors affecting them.

METHODS

We conducted a survey of refractory asthma with non-cystic fibrosis bronchiectasis/bronchiolitis in Japan. Cases were classified into three groups, based on the latest fractional exhaled NO (FeNO) level (32 ppb for the threshold) and blood eosinophil counts (320/µL for the threshold): high (type 2-high) or low (type 2-low) FeNO and eosinophil and high FeNO or eosinophil (type 2-intermediate). Clinical courses in groups and factors affecting them were analysed.

RESULTS

In total, 216 cases from 81 facilities were reported, and 142 were stratified: 34, 40 and 68 into the type 2-high, -intermediate and -low groups, respectively. The frequency of bronchopneumonia and exacerbations requiring antibiotics and gram-negative bacteria detection rates were highest in the type 2-low group. Eighty-seven cases had paired latest and oldest available data of FeNO and eosinophil counts; they were analysed for inflammatory transition patterns. Among former type 2-high and -intermediate groups, 32% had recently transitioned to the -low group, to which relatively low FeNO in the past and oral corticosteroid use contributed. Lastly, in cases treated with moderate to high doses of inhaled corticosteroids, the frequencies of exacerbations requiring antibiotics were found to be higher in cases with more severe airway lesions and lower FeNO.

CONCLUSIONS

Bronchiectasis/bronchiolitis-complicated refractory asthma is heterogeneous. In patients with sputum symptoms and low FeNO, airway colonisation of pathogenic bacteria and infectious episodes are common; thus, corticosteroids should be carefully used.

Bronchiectasis in severe asthma and asthmatic components in bronchiectasis

Asthma and bronchiectasis are different diseases; however, differentiating them can be difficult because they share several symptomatic and physiological similarities. Approximately 20% of patients with bronchiectasis have eosinophilic inflammation, 34% show wheezing, and 7-46% have comorbid asthma, although comorbidity with severe asthma may be limited as shown in 3.3% of cases of bronchiectasis. Meanwhile, 25-68% of patients with severe asthma have comorbid bronchiectasis, and at least two phenotypes are present in the accompanying bronchiectasis: eosinophilic bronchiectasis and chronic infectious bronchiolitis/bronchiectasis. Recent studies show that type-2-targeted biologics are effective for eosinophilic bronchiectasis and theoretically effective for some of the remaining cases when used before oral corticosteroids. Further studies are needed to identify treatment strategies for severe asthma with comorbid bronchiectasis and vice versa.

Cost-effectiveness analysis of dupilumab among patients with oral corticosteroid-dependent uncontrolled severe asthma in Japan

Background: Asthma is a common, chronic inflammatory airway disorder, with up to 1,177,000 people receiving asthma treatment in Japan. Dupilumab is a first-in-class, monoclonal antibody for the treatment of atopic diseases, including persistent asthma. The objective of this study was to assess the cost-effectiveness of dupilumab, compared with other biologics, as add-on treatment to background therapy in patients aged ≥12 years with uncontrolled, persistent asthma in Japan.Methods: A life-time Markov cohort model was used to conduct cost-effectiveness analysis from the Japanese healthcare payer perspective with an annual discount rate of 2%. Dupilumab was compared with benralizumab and mepolizumab, and against omalizumab (as a hypothetical scenario). Inputs were informed by dupilumab clinical trials (VENTURE [NCT02528214] and QUEST [NCT02414854] trials), the literature, official Japanese sources and expert opinions.Results: The base case results suggest that treatment with dupilumab leads to fewer severe exacerbations and increased life-years (LYs) and quality-adjusted LYs (QALYs) than benralizumab and mepolizumab. At a willingness-to-pay (WTP) threshold of ¥5,000,000 per QALY gained, dupilumab was the dominant strategy (lower cost, increased QALYs) versus benralizumab, and cost-effective versus mepolizumab with an incremental cost effectiveness ratio (ICER) of ¥1,010,921 (US$9,190, US$1=¥110). Versus omalizumab, dupilumab was not cost-effective (ICER of ¥10,802,368 [US$98,203]).Conclusions: In Japan, dupilumab, as an add-on to background therapy, is economically dominant compared with benralizumab, and cost-effective versus mepolizumab.

The importance of central airway dilatation in patients with bronchiolitis obliterans

Background

Bronchiolitis obliterans (BO) is a clinical syndrome characterised by progressive small airway obstruction, causing significant morbidity and mortality. Central airway dilatation is one of its radiological characteristics, but little is known about the clinical and pathological associations between airway dilatation and BO.

Methods

This retrospective study consecutively included patients who underwent lung transplantation due to BO at Kyoto University Hospital from 2009 to 2019. Demographic and histopathological findings of the resected lungs were compared between patients with and without airway dilatation measured by chest computed tomography (CT) at registration for lung transplantation.

Results

Of a total of 38 included patients (median age, 30 years), 34 (89%) had a history of hematopoietic stem-cell transplantation, and 22 (58%) had airway dilatation based on CT. Patients with airway dilatation had a higher frequency of Pseudomonas aeruginosa isolation with greater residual volume than those without airway dilatation. Quantitative CT analysis revealed an increase in lung volume to predictive total lung capacity and a percentage of low attenuation volume <−950 HU at inspiration in association with the extent of airway dilatation. Airway dilatation on CT was associated with an increased number of bronchioles with concentric narrowing of the lumen and thickening of the subepithelium of the walls on histology.

Conclusions

In patients with BO, airway dilatation may reflect increased residual volume or air trapping and pathological extent of obstructive bronchioles, accompanied by a risk of Pseudomonas aeruginosa isolation. More attention should be paid to the development of airway dilatation in the management of BO.

In patients with bronchiolitis obliterans (BO), airway dilatation may reflect air trapping and the pathological extent of obstructive bronchioles. More attention should be paid to airway dilatation in the management of BO.https://bit.ly/3w7cRV6

Diaphragmatic excursion is correlated with the improvement in exercise tolerance after pulmonary rehabilitation in patients with chronic obstructive pulmonary disease

BACKGROUND

In patients with chronic obstructive pulmonary disease (COPD), the maximum level of diaphragm excursion (DEmax) is correlated with dynamic lung hyperinflation and exercise tolerance. This study aimed to elucidate the utility of DEmax to predict the improvement in exercise tolerance after pulmonary rehabilitation (PR) in patients with COPD.

METHODS

This was a prospective cohort study. Of the 62 patients with stable COPD who participated in the outpatient PR programme from April 2018 to February 2021, 50 completed the programme. Six-minute walk distance (6MWD) was performed to evaluate exercise tolerance, and ultrasonography was performed to measure DEmax. Responders to PR in exercise capacity were defined as patients who demonstrated an increase of > 30 m in 6MWD. The receiver operating characteristic (ROC) curve was used to determine the cut-off point of DEmax to predict responses to PR.

RESULTS

Baseline levels of forced expiratory volume in 1 s, 6MWD, maximum inspiratory pressure, DEmax and quadriceps muscle strength were significantly higher, and peak dyspnoea of modified Borg (mBorg) scale score was lower in responders (n = 30) than in non-responders (n = 20) to PR (p < 0.01). In multivariate analysis, DEmax was significantly correlated with an increase of > 30 m in 6MWD. The area under the ROC curve of DEmax to predict responders was 0.915, with a sensitivity and specificity of 83% and 95%, respectively, at a cut-off value of 44.9 mm of DEmax.

CONCLUSION

DEmax could adequately predict the improvement in exercise tolerance after PR in patients with COPD.

Deep learning-based plaque quantification from coronary computed tomography angiography: external validation and comparison with intravascular ultrasound

Background

Atherosclerotic plaque quantification from coronary computed tomography angiography (CTA) enables accurate assessment of coronary artery disease burden, progression, and prognosis. However, quantitative plaque analysis is time-consuming and requires high expertise. We sought to develop and externally validate an artificial intelligence (AI)-based deep learning (DL) approach for CTA-derived measures of plaque volume and stenosis severity. We compared the performance of DL to expert readers and the gold standard of intravascular ultrasound (IVUS).

Methods

This was a multicenter study of patients undergoing coronary CTA at 11 sites, with software-based quantitative plaque measurements performed at a per-lesion level by expert readers. AI-based plaque analysis was performed by a DL novel convolutional neural network which automatically segmented the coronary artery wall, lumen, and plaque for the computation of plaque volume and stenosis severity. Using expert measurements as ground truth, the DL algorithm was trained on 887 patients (4,686 lesions). Thereafter, the algorithm was applied to an independent test set of 221 patients (1,234 lesions), which included an external validation cohort of 171 patients from the SCOT-HEART (Scottish Computed Tomography of the Heart) trial as well as 50 patients who underwent IVUS within one month of CTA. We report the performance of AI-based plaque analysis in the independent test set.

Results

Within the external validation cohort, there was excellent agreement between DL and expert reader measurements of total plaque volume (intraclass correlation coefficient [ICC] 0.876), noncalcified plaque volume (ICC 0.869), and percent diameter stenosis (ICC 0.850; all p&lt;0.001). When compared with IVUS, there was excellent agreement for DL total plaque volume (ICC 0.945), total plaque burden (ICC 0.853), minimal luminal area (ICC 0.864), and percent area stenosis (ICC 0.805; all p&lt;0.001); with strong correlation between DL and IVUS for total plaque volume (r=0.915; p&lt;0.001; Figure). The average DL plaque analysis time was 20 seconds per patient, compared with 25–30 minutes taken by experts.

Conclusions

AI-based plaque quantification from coronary CTA using an externally validated DL approach enables rapid measurements of plaque volume and stenosis severity in close agreement with expert readers and IVUS.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): National Heart, Lung, and Blood Institute, United States

The impact of the COVID-19 pandemic on asthma treatment in Japan: Perspectives based on doctors' views

The coronavirus disease 2019 (COVID-19) pandemic has had a great influence on medical practice in Japan. In this study, an online questionnaire-based survey was conducted among doctors routinely involved in the treatment of asthma. The questions included in the survey pertained to their thoughts on asthma treatment amidst COVID-19, changes in their clinical approach toward patients with asthma, and the behavioral changes in patients in the pandemic era. The results revealed a significant impact of the pandemic on asthma treatment. Regardless of whether or not they were directly involved in the treatment of patients with COVID-19, the doctors had avoided using nebulizers in outpatient wards/clinics and routine pulmonary function testing. An increase in canceled appointments and inappropriate/non-adherence to treatment among their patients were noticeable. Furthermore, the survey revealed an extensive impact of the pandemic on the doctors engaged in asthma treatment irrespective of the differences in their medical backgrounds.

Change in Contralateral Muscle Blood Volume During Passive Unilateral Muscle Stretching Before and After Surgery

OBJECTIVE

Passive muscle stretching is a common physical therapy for critically ill patients in the intensive care units. This study aimed to evaluate the effects of unilateral passive stretching of the gastrocnemius muscle (GM) before and after surgery on blood volume (BV) in the contralateral (non-stretched) GM in patients who are sedated after surgery.

METHODS

We enrolled eight patients with esophageal cancer. The patients completed two sessions of passive cyclical stretching (20-s hold, 10-s release, 10 cycles) of the right GM: one before surgery (awake) and one after (under sedation). We used near-infrared spectroscopy to measure the BV in the stretched and contralateral GM. BV kinetics were compared between the ipsilateral and contralateral GM.

RESULTS

In seven of the eight patients, BV in the stretched GM decreased during stretching and increased during the stretch-relaxation phase, both before and after surgery. Both before and after surgery, the change in the BV in the contralateral GM was inversely synchronized to the stretching cycle.

CONCLUSIONS

Unilateral passive stretching of the GM influenced the microcirculation of the contralateral GM. The mechanism underlying the synchronous change in the BV in the contralateral GM remains to be clarified.

Core-shell hydrogel microfiber-expanded pluripotent stem cell-derived lung progenitors applicable to lung reconstruction in vivo

Lung transplantation is the only treatment available for end-stage lung diseases; however, donor shortage is a global issue. The use of human pluripotent stem cells (hPSCs) for organ regeneration is a promising approach. Nevertheless, methods for the expansion of isolated hPSC-derived lung progenitors (hLPs) for transplantation purposes have not yet been reported. Herein, we established an expansion system of hLPs based on their three-dimensional culture in core-shell hydrogel microfibers, that ensures the maintenance of their bipotency for differentiation into alveolar and airway epithelial cells including alveolar type II (AT2) cells. Further, we developed an efficient in vivo transplantation method using an endoscope-assisted transtracheal administration system; the successful engraftment and in vivo differentiation of hLPs into alveolar epithelial cells (incorporated into the alveoli) was observed. Importantly, expanded hLPs in the context of microfibers were successfully transplanted into the murine lungs, opening avenues for cell-based therapies of lung diseases. Therefore, our novel method has potential regenerative medicine applications; additionally, the high-quality hLPs and AT2 cells generated via the microfiber-based technology are valuable for drug discovery purposes.

Pneumonia Caused by Severe Acute Respiratory Syndrome Coronavirus 2 and Influenza Virus: A Multicenter Comparative Study

Background

Detailed differences in clinical information between severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pneumonia (CP), which is the main phenotype of SARS-CoV-2 disease, and influenza pneumonia (IP) are still unclear.

Methods

A prospective, multicenter cohort study was conducted by including patients with CP who were hospitalized between January and June 2020 and a retrospective cohort of patients with IP hospitalized from 2009 to 2020. We compared the clinical presentations and studied the prognostic factors of CP and IP.

Results

Compared with the IP group (n = 66), in the multivariate analysis, the CP group (n = 362) had a lower percentage of patients with underlying asthma or chronic obstructive pulmonary disease (P < .01), lower neutrophil-to-lymphocyte ratio (P < .01), lower systolic blood pressure (P < .01), higher diastolic blood pressure (P < .01), lower aspartate aminotransferase level (P < .05), higher serum sodium level (P < .05), and more frequent multilobar infiltrates (P < .05). The diagnostic scoring system based on these findings showed excellent differentiation between CP and IP (area under the receiver operating characteristic curve, 0.889). Moreover, the prognostic predictors were different between CP and IP.

Conclusions

Comprehensive differences between CP and IP were revealed, highlighting the need for early differentiation between these 2 pneumonias in clinical settings.

Risk factors associated with methicillin-resistant Staphylococcus aureus isolation from serially collected sputum samples of patients hospitalized with pneumonia

INTRODUCTION

Risk factors associated with the new detection of methicillin-resistant Staphylococcus aureus (MRSA) during hospitalization remain unclear. This study aimed to identify risk factors associated with MRSA isolation from the sputum of patients admitted with pneumonia, during their hospitalization.

METHODS

Patients were prospectively enrolled from 2003 to 2012. Sputum samples were collected for bacterial cultures on days 1, 4, 7, 11, and 14 of hospitalization and thereafter. Cases of MRSA first isolated from sputum obtained before day 4 were defined as "carriage on admission." Cases of MRSA first isolated on day 4 and thereafter, were defined as "new detection after admission." Statistical analysis was used to investigate the risk factors associated with MRSA isolation.

RESULTS

MRSA was isolated from 167 of 1,008 patients (carriage: 47; new detection: 120). Multivariate analysis revealed that the risk factors for MRSA carriage were activities of daily living (ADL) disability prior to admission (odds ratio [OR], 2.92; 95% confidence interval [CI], 1.37-6.22) and hospitalization within the previous 90 days (OR, 3.75; 95% CI, 1.90-7.41). ADL disability prior to admission (risk ratio [RR], 1.82; 95% CI, 1.17-2.84) and a high pneumonia severity index score upon admission (RR, 2.20; 95% CI, 1.37-3.65) were risk factors for new detection of MRSA.

CONCLUSIONS

Several risk factors were found to be associated with MRSA carriage and/or its new detection, based on the sputum samples from patients admitted with pneumonia. These factors may be indicators for selective surveillance and the early implementation of infection control measures.

Gastroesophageal reflux disease is a risk factor for sputum production in the general population: the Nagahama study

BACKGROUND

Chronic sputum production in the general population is historically associated with clinical indices including male sex and smoking history. However, its relationship with gastroesophageal reflux disease (GERD), which may prove an underlying factor in sputum production, is unclear. We aimed to clarify factors associated with sputum production in the general population in cross-sectional and longitudinal manners.

METHODS

In the Nagahama study, a community-based cohort study, 9804 subjects were recruited between 2008 and 2010 (baseline assessment), 8293 of whom were followed from 2013 to 2015 (follow-up assessment). This study contained a self-completed questionnaire which included medical history, assessment of sputum production, and a frequency scale for symptoms of GERD. A Frequency Scale for Symptoms of Gastroesophageal Reflux Disease score of ≥ 8 was defined as GERD. In addition to the frequency of sputum production at each assessment, frequency of persistent sputum production defined as sputum production at both assessments was examined.

RESULTS

Frequency of sputum production was 32.0% at baseline and 34.5% at follow-up. Multivariable analysis demonstrated that sputum production at baseline was significantly associated with GERD [odds ratio (OR), 1.92; 95% confidence interval (CI) 1.73-2.13] and post-nasal drip (PND) (OR, 2.40; 95% CI 2.15-2.68), independent of other known factors such as older age, male sex and smoking history. These associations between sputum production and GERD or PND were also observed at follow-up. In longitudinal analysis, 19.4% had persistent sputum production and 12.3% had transient sputum production, i.e., at baseline only. Multivariable analysis for risk of persistence of sputum production revealed that persistent sputum production was associated with GERD and PND, in addition to the known risk factors listed above. The proportion of subjects with GERD at both assessments was highest among subjects with persistent sputum production.

CONCLUSIONS

Cross-sectional and longitudinal analysis demonstrated an association in the general population between sputum production and GERD, as well as PND, independent of known risk factors. The presence of GERD should be assessed in patients complaining of sputum production.