Airflow Obstruction Research Articles

Type-2 Inflammation in Health and Disease: Prevalence, Risk Factors and Multimorbidity

Background: In patients with airflow obstruction, the levels of biomarkers of Type-2 (T2) inflammation serve to predict the effectiveness of inhaled corticosteroid and biological therapies. Elevated biomarkers of T2 inflammation, including fractional exhaled nitric oxide (FeNO, ≥20 ppb) and blood eosinophil counts (BEC, ≥300 cells/µL), were investigated in a population-based cohort of the Austrian LEAD study. Methods: A total of 4976 individuals (aged 18–82 years) were categorised into four groups based on their FeNO and BEC levels: normal with FeNO < 20 ppb and BEC < 300 cells/µL (n = 2634); FeNO ≥ 20 ppb only (n = 1623); BEC ≥ 300 cells/µL only (n = 340); and FeNO ≥ 20 ppb and BEC ≥ 300 cells/µL (n = 379). Results: In age- and sex-adjusted regression models, individuals with elevated BEC only were most associated with chronic cough and sputum production (odds ratios [95% CI]: 1.22 [0.78, 1.84] and 1.37 [1.13, 2.62], respectively), whilst individuals with both elevated T2 biomarkers were most associated with wheezing, dyspnoea and asthma (odds ratios [95% CI]: 2.27 [1.56, 3.26], 1.32 [0.64, 2.50] and 3.63 [2.69, 4.88] respectively). Elevated levels of both FeNO and BEC presented an additive effect in extrapulmonary conditions, particularly in allergy, eczema and rhino conjunctivitis (odds ratios [95% CI]: 2.30 [1.84, 2.88], 1.37 [1.03, 1.81] and 2.95 [2.34, 3.70], respectively). Conclusions: T2 inflammation marked by elevated levels of FeNO and/or BEC is not only associated with respiratory conditions but also extends to extrapulmonary characteristics, with an additive effect.

Persistent Airflow Limitation Prediction and Risk Factor Analysis Among Asthmatic Children: A Retrospective Cohort Study.

A minority of asthmatic children develop persistent airflow limitation (PAL), associated with an increased risk of chronic airflow obstruction and poor prognosis. This study aimed to identify risk factors for PAL and develop a prediction model to identify high-risk asthmatic children. This retrospective study included 2072 children (5-16 years) with asthma. After a 2-year follow-up, patients were categorized into non-PAL, reversible PAL (RPAL), and irreversible PAL (IPAL) groups. Logistic regression (LR) was used to identify independent risk factors for RPAL and IPAL. A prediction model based on multivariate LR was developed and validated to identify asthmatic children at high risk of developing PAL. A nomogram was created for visualization. Among the 2072 asthmatic patients, 14.72% (n = 305) developed PAL. Asthma exacerbation history (OR 1.80, 95% CI 1.03-3.01) and poor adherence (OR 1.83, 95% CI 1.26-2.65) were independent risk factors of RPAL. Independent risk factors for IPAL were BMI over 19.0 kg/m2 (OR: 1.81, 95% CI: 1.03-3.21) and a history of pneumonia (OR: 2.40, 95% CI: 1.30-4.26). The prediction model incorporated nine variables and showed good discriminatory ability, with AUC values of 0.79 (95% CI: 0.76-0.81) for the training set, 0.76 (95% CI: 0.76-0.77) for internal validation, and 0.73 (95% CI: 0.64-0.81) for temporal validation. Asthma exacerbation history and poor adherence were independent risk factors for developing RPAL. BMI over 19.0 kg/m2 and a history of pneumonia were risk factors for IPAL. Our prediction model effectively identified asthmatic children at high risk of developing PAL.

Associations of pulmonary microvascular blood volume with per cent emphysema and CT emphysema subtypes in the community: the MESA Lung study

BackgroundPulmonary microvasculature alterations are implicated in emphysema pathogenesis, but the association between pulmonary microvascular blood volume (PMBV) and emphysema has not been directly assessed at scale, and prior studies have...

Prevalence and clinical significance of pre- and post-bronchodilator airflow obstruction in COPD patients

Prevalence and clinical significance of pre- and post-bronchodilator airflow obstruction in COPD patients

Traditional Chinese Herbal Medicine: Therapeutic Potential in Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) is characterized by persistent airflow obstruction and manifested by symptoms such as chronic cough, sputum, and dyspnea. Traditional Chinese medicine (TCM) has long been used to treat COPD. This article summarizes potential Chinese herbal medicines (CHM) for COPD treatment through a literature review and collation. The findings highlight 14 kinds of effective CHM for COPD, including Scutellaria radix, Salvia miltiorrhiza radix et rhizoma, Hippophae fructus, Ginseng radix et rhizoma, and Astragali radix. Flavonoids, terpenoids, alkaloids, and volatile oil constituents are the main bioactive components for the treatment of COPD. They mainly inhibit the tumor necrosis factor alpha/nuclear factor kappa B (TNF-α/NF-κB) signaling pathway by reducing the production and release of inflammatory factors such as interleukin 1 beta (IL-1β), interleukin 6 (IL-6), interleukin 8 (IL-8), TNF-α, and NF-κB, thereby reducing inflammation in lungs of rats with COPD and protect the lung tissues. Some active ingredients can inhibit toll-like receptor 4 (TLR4), mitogen-activated protein kinase (MAPK), phosphoinositide 3-kinase-protein kinase B (PI3K-Akt), Janus kinase-signal transducer and activator of transcription (JAK-STAT), and transforming growth factor beta (TGF-β) signaling pathways to express anti-inflammatory activity. This work establishes a foundation for using CHM in COPD treatment and offers new insights and approaches for developing novel anti-COPD drugs.

Neutrophilic inflammation in sputum or blood does not define a clinically distinct asthma phenotype in ATLANTIS

IntroductionNeutrophilic asthma has been suggested to be a clinically distinct phenotype characterized by more severe airflow obstruction and higher exacerbation risk. However, this has only been assessed in few and smaller studies, using different cut-offs to define neutrophilia, and with conflicting results.We used data from ATLANTIS, an observational longitudinal study including a large number of patients with asthma and healthy controls.AimTo examine if neutrophilic inflammation, either in sputum or blood, is more prevalent in asthma and whether it correlates with disease severity.MethodsATLANTIS included 773 asthma patients, with blood collected from 767 (99%) and sputum from 228 patients (30%). Data were available from 244 healthy controls, all providing blood and 126 (52%) providing sputum. Asthma patients were characterized including parameters of large and small airways disease at baseline and after 6- and 12-months follow-up. Sputum and blood neutrophilia were defined as values exceeding the upper quartile in asthma patients.ResultsThe prevalence of sputum neutrophilia did not differ between asthma patients and healthy controls. Asthma patients with sputum neutrophilia did not display more severe symptoms, large or small airways disease, or more frequent exacerbations. Blood neutrophilia was more common in asthma and associated with higher BMI, female sex, current smoking and systemic corticosteroid use. Patients with blood neutrophilia had a statistically significant, but small, increase in RV/TLC. Blood neutrophilia was not associated with large or small airways disease, or exacerbation risk.ConclusionSputum and blood neutrophilia do not define a distinct clinical phenotype in asthma.

Innovative Approach of High-Throughput Screening in the Drug Discovery Quest for Chronic Bronchitis Treatment

Chronic bronchitis (CB) is a challenging condition that worsens over time. Patients continue to experience an abundance of symptoms despite their best attempts to manage them. The etiology of CB is goblet cell overproduction and mucus hypersecretion, which aggravates airflow obstruction by luminal blockage of small airways, epithelial remodeling and modification of airway surface tension that predisposes to collapse. Larger randomized controlled trials are required to validate the pilot data that are currently accessible and assess the treatment’s durability as therapies are still in the early stages of clinical development. To overcome the prevailing increase in CB with the rise in air pollution globally, this study proposes a de novo drug discovery candidate for the effective treatment of CB. With the aid of cutting-edge technology of high-throughput screening, a phytochemical, apigenin, has been administered to target the Beta-2 adrenergic receptor protein and utilized as an exemplary ligand to target the discovery of a suitable drug candidate for Beta-2 adrenergic receptor protein. The drug likeness scores, no evident toxicity and binding affinity –9.092 kcal/mol the “CHEMBL294878” proves to be a potential drug candidate discovered for CB. A therapeutic drug specifically meant to treat CB can be developed with the help of the computational data provided by the research presented in this study.

Clinical characteristics of chronic obstructive pulmonary disease according to smoking status.

COPD can be caused by various factors, including lung infections, asthma, air pollution, childhood growth disorders, and genetic factors, although smoking is a predominant risk factor. The main pathological mechanisms in COPD involve small airway disease, emphysema, mucus hypersecretion, and vascular disorders. COPD in non-smokers is characterized by normal FEV1 decline, equal distribution of sex, younger age of onset, fewer comorbidities, milder airflow obstruction, normal diffusing capacity of the lungs for carbon monoxide (DLCO) and radiological features such as more air-trapping and less severe emphysema, compared to COPD in smokers. COPD in non-smokers is still accompanied by a high prevalence of acute exacerbation almost equal to COPD in smokers. Moreover, COPD per se is an independent risk factor for the development of lung cancer, irrespective of smoking status. Considering that COPD coexists with numerous comorbidities, effective management of these comorbidities is essential, and multifaceted efforts are required for the comprehensive treatment of COPD.

Comparison of the Determinants of the "Chronic Obstructive Pulmonary Disease Assessment Test" (CAT) and the "Asthma Control Test" (ACT) in Patients with Asthma-COPD Overlap.

Objective: The objective of this study was to investigate which of two short questionnaires, the Asthma Control Test (ACT) or the COPD Assessment Test (CAT), correlates better with severity variables and whether they share similar determinants in patients with asthma-COPD overlap. Method: This observational, cross-sectional, multicentric study included smokers and former smokers of more than 10 pack-years, with non-fully reversible airflow obstruction and either a concomitant diagnosis of asthma or signs of type 2 inflammation, from 15 centres in Spain. Results: A total of 157 patients were included, 109 (69.4%) were men, the mean age was 63.3 (SD: 9) years and the mean FEV1 (%) was 59.7% (SD: 20.5%). The mean CAT score was 14.5 (SD: 8.7), and the mean ACT score was 17.9 (SD: 5.2). Both scores showed good correlations (r = 0.717; p < 0.001). In the multivariate analysis, the Hospital Anxiety and Depression Scale and mMRC dyspnoea scores were independently and significantly associated with both the CAT and ACT scores; however, age was only significantly associated with the CAT, and the EQ-5D scores and the number of exacerbations in the previous year were only significantly associated with the ACT scores. The ACT had a slightly better predictive value for exacerbations than the CAT (AUC = 0.70 (95% CI: 0.62 to 0.79 vs. 0.65 (95% CI: 0.56 to 0.74))). Conclusions: There is a good correlation between ACT and CAT scores in patients with ACO. However, severe patients scored worse on the CAT than the ACT. Anxiety, depression and dyspnoea were significantly associated with both the CAT and ACT scores. The ACT was a slightly better predictor of exacerbations than the CAT in this population.

Transforming Care in SEA: Evidence and Considerations for Evolution of the Current Treatment Paradigm

This article reviews an industry symposium held on 8 September 2024 as part of the European Respiratory Society (ERS) Congress 2024 in Vienna, Austria, which brought together four experts to discuss the current treatment paradigm for severe eosinophilic asthma (SEA), including the role of biologics and background medication tapering. Katrin Milger-Kneidinger, Professor of Respiratory Medicine at the University Hospital of the Ludwig Maximilian University Munich (LMU), in Germany, and the MedUni Graz, in Austria, explored the critical role eosinophils play in SEA pathology and how biologic therapies targeting eosinophils can address key disease features, including airway remodelling, airway hyperresponsiveness (AHR), and mucus production. Felix Herth, Professor of Pulmonary and Critical Care Medicine at Thoraxklinik Heidelberg, Heidelberg University Hospital, in Germany, discussed persistent airflow obstruction (PAO) in patients with SEA, focusing on a typical patient profile to understand the clinical manifestation and opportunities for management. Stephanie Korn, Professor of Pulmonary and Respiratory Medicine at Thoraxklinik Heidelberg, Heidelberg University Hospital, in Germany, and Head of the Clinical Research Centre, Institute für Klinische Forschung (IKP) Pneumologie in Mainz, Germany, presented on remission as a clinical target in SEA, focusing on how biologics can help achieve remission in some patients. Lastly, in a discussion led by symposium chair Stefano Del Giacco, Professor of Medicine, Allergy, and Clinical Immunology, at the University of Cagliari, Sardinia, in Italy, the experts agreed that a positive practice change would be to get more patients with relevant clinical manifestations on biologics, and that background medication tapering, when appropriate, could lead to improved patient outcomes and quality of life (QoL) in SEA.

CRP Levels and Vitamin D as Predictors of Asthma Control: A Data-Driven Approach

Background: Asthma is a chronic inflammatory disease of the airways characterized by episodic exacerbations and airflow obstruction. Elevated C-reactive protein (CRP) levels indicate systemic inflammation and are associated with increased disease severity in asthma. Additionally, vitamin D is thought to modulate immune responses and inflammation, potentially influencing asthma control. This study explores the relationships between CRP levels, vitamin D levels, and asthma control, as measured by the Asthma Control Test (ACT). Objectives: The primary objective of this study was to assess the correlation between CRP levels, vitamin D levels, and asthma control in adult patients with asthma. The study aimed to determine whether CRP and vitamin D could serve as predictive markers for asthma control. Methods: This single-center, prospective observational study enrolled 40 adult patients with confirmed asthma from the outpatient pulmonary clinic of ESIC Government Hospital, Guwahati, Assam, India. Asthma control was evaluated using the ACT, with scores categorized as well-controlled (ACT ≥ 20) or poorly controlled (ACT &lt; 20). Serum CRP and vitamin D levels were measured using the ELISA method. Pearson’s correlation coefficient and ANOVA were employed to analyze the relationships between these variables. Results: The study found a moderate negative correlation between CRP levels and ACT scores (r = -0.58), indicating that higher CRP levels were associated with poorer asthma control. Patients with CRP levels greater than 10 mg/dL had significantly lower mean ACT scores compared to those with lower CRP levels. In contrast, a strong positive correlation was observed between vitamin D levels and ACT scores (r = 0.879), with higher vitamin D levels associated with better asthma control. The ANOVA test revealed significant differences in ACT scores across different vitamin D and CRP categories (p &lt; 0.05). Conclusions: The study suggests that elevated CRP levels are indicative of poorer asthma control, while higher vitamin D levels are associated with better control of asthma. CRP and vitamin D levels may serve as valuable biomarkers for assessing asthma severity and guiding treatment strategies. However, the variability in response to vitamin D supplementation highlighted the need for personalized approaches to asthma management. Further research is required to confirm these findings and explore the underlying mechanisms.

CHF6523 data suggest that the phosphoinositide 3-kinase delta isoform is not a suitable target for the management of COPD

BackgroundChronic obstructive pulmonary disease (COPD) is a chronic inflammatory condition. Given patients with COPD continue to experience exacerbations despite the availability of effective therapies, anti-inflammatory treatments targeting novel pathways are needed. Kinases, notably the phosphoinositide 3-kinases (PI3K), are thought to be involved in chronic airway inflammation, with this pathway proposed as a critical regulator of inflammation and oxidative stress response in COPD. CHF6523 is an inhaled PI3Kδ inhibitor that has shown positive preclinical results. This manuscript reports the results of a study of CHF6523 in patients with stable COPD (chronic bronchitis phenotype), and who had evidence of type-2 inflammation.MethodsThis randomised, double-blind, placebo-controlled, two-way crossover study comprised two 28-day treatment periods separated by a 28-day washout. Patients (N = 44) inhaled CHF6523 in one period, and placebo in the other, both twice daily. The primary objective was to assess the safety and tolerability of CHF6523; the secondary objective was to assess CHF6523 pharmacokinetics. Exploratory endpoints included target engagement (the relative reduction in phosphatidylinositol (3,4,5)-trisphosphate [PIP3]), pharmacodynamic evaluations such as airflow obstruction, and hyperinflation, and to identify biomarker(s) of drug response using proteomics and transcriptomics.ResultsCHF6523 plasma pharmacokinetics were characterised by an early maximum concentration (Cmax), reached 15 and 10 min after dosing on Days 1 and 28, respectively, followed by a rapid decline. Systemic exposure on Day 28 showed limited accumulation, with ratios < 1.6 for Cmax and area under the curve from 0 to 12 h post-dose, and with steady state achieved on Day 20. Target engagement was confirmed by a significant 29.7% reduction from baseline in induced sputum PIP3 (29.5% reduction vs. placebo; adjusted ratio 0.705 [0.580, 0.856]; p = 0.001), but this did not translate into an anti-inflammatory pharmacodynamic effect, as assessed through measures including biomarkers and multi-omics. Additionally, although CHF6523 was generally well-tolerated, 95.2% of patients reported cough as an adverse event, most mild to moderate and resolving within one-hour post-dose.ConclusionsThese data, together with those from other PI3K inhibitors, suggest that PI3Kδ is not a suitable pathway for the management of COPD, as the achieved target engagement did not translate into any pharmacodynamic anti-inflammatory effect.Trial registrationClinicalTrials.gov (NCT04032535); posted 23rd July 2019.

Reference formulas for chest CT-derived lobar volumes in the lung-healthy general population.

Lung hyperinflation, a key contributor to dyspnea in chronic obstructive pulmonary disease (COPD), can be quantified via chest computed tomography (CT). Establishing reference equations for lobar volumes and total lung volume (TLV) can aid in evaluating lobar hyperinflation, especially for targeted lung volume reduction therapies. The Imaging in Lifelines study (ImaLife) comprises 11,729 participants aged 45 and above with analyzed inspiratory low-dose thoracic CT scans. Lung and lobar volumes were measured using an automatic AI-based segmentation algorithm (LungSeg). For the main analysis, participants were excluded if they had self-reported COPD/asthma, lung disease on CT, airflow obstruction on lung function testing, were currently smoking, aged over 80 years, or had height outside the 99% confidence interval. Reference equations for TLV and lobar volumes were determined using linear regression considering age and height, stratified by sex. For the subanalysis, participants who were currently smoking or experiencing airflow obstruction were compared to the group of the main analysis. The study included 7306 lung-healthy participants, 97.5% Caucasian, 43.6% men, with mean age of 60.3 ± 9.5 years. Lung and lobar volumes generally increased with age and height. Men consistently had higher volumes than women when adjusted for height. R2 values ranged from 7.8 to 19.9%. In smokers and those with airway obstruction, volumes were larger than in lung-healthy groups, with the largest increases measured in the upper lobes. The established reference equations for CT-derived TLV and lobar volumes provide a standardized interpretation for individuals aged 45 to 80 of Northern European descent. Question Lobar lung volumes can be derived from inspiratory CT scans, but healthy-lung reference values are lacking. Findings Lung and lobar volumes generally increased with age and height. Reference equations for lung/lobar volumes were derived from a sizeable lung-healthy population. Clinical relevance This study provides reference equations for inspiratory CT-derived lung and lobar volumes in a lung-healthy population, potentially useful for assessing candidates for lung volume reduction therapies, for lobe removal in lung cancer patients, and in case of restrictive pulmonary diseases.

CT Radiomics Features Predict Change in Lung Density and Rate of Emphysema Progression.

Rationale Emphysema progression is heterogeneous. Predicting temporal changes in lung density and detecting rapid progressors may facilitate selection of individuals for targeted therapies. Objective To test whether computed tomography (CT) radiomics can be used to predict changes in lung density and detect rapid progressors. Methods We extracted radiomics features from inspiratory chest CT in 4,575 subjects with and without airflow obstruction at enrollment, who completed a follow-up visit at approximately 5 years. We quantified emphysema using adjusted lung density (ALD) and estimated emphysema progression as the annualized change in ALD (∆ALD/year) between visits. We categorized participants into rapid progressors (>1% ∆ALD/year) and stable disease (≤1% ∆ALD/year). A gradient boosting model was used (1) to predict ALD at 5-years and (2) to identify rapid progressors. Four models using demographics (base clinical model); CT density; radiomics; and combined features (clinical, radiomics, and CT density) were evaluated and tested. Results There were 1,773 (38.8%) rapid progressors. For predicting ALD at 5-years in the 20% held-out data, the base model explained 31% of the variance (adjusted R2 = 0.31) whereas R2 was 0.74 for the CT density model, 0.66 for the radiomics-only model, and 0.77 for the combined features model. For detecting rapid progressors, the base model (AUC = 0.57, 95%CI 0.53-0.61) was outperformed by the radiomics-only model (AUC = 0.73, 95%CI 0.69-0.76, ∆ =0.0003, p < 0.001) and the combined model (AUC = 0.74, 95%CI 0.71-0.77, ∆ = 0.0003, p < 0.001). Conclusions Parenchymal and airway radiomics features derived from inspiratory scans can be used to predict temporal changes in lung density and help identify rapid progressors.

Dedicated low-cost electronic ocarina for people with COPD: Rationale and prototype development

ABSTRACT Introduction Chronic obstructive pulmonary disease (COPD) is a condition characterized by airflow obstruction which can lead to physical and psychosocial challenges, with a higher prevalence in developing countries. Non-pharmacological interventions for this group of people include pulmonary rehabilitation as well as music interventions. Although music technology was recommended to adjust to the user’s breathing capacity for music-making and to gather information about their performance, music therapy trials used acoustic wind instruments for their rehabilitation. This interdisciplinary project aims to develop a dedicated electronic wind instrument for people with COPD. Method This project follows a systematic prototype methodology that includes product research, instrument development, and user validation. Based in Brazil, our team has decided on an electronic ocarina based on its cultural features, its popularity as a digital application, and its potential for respiratory training. Unlike existing technologies, the prototype intends to be dedicated and a low-cost solution. Results The development process includes decision making about the appropriate mouthpiece, sensors, Arduino, pushbuttons, 3-D printing projects, building a MIDI interface and a dedicated software. This is an ongoing project, and our team is in the MIDI interface development stage. We aim to run the first hardware trial with users so that we can integrate their feedback into the functional prototype and the dedicated software for the following trials. Discussion This project’s strengths rely on the innovation of building viable electronic wind instruments that can facilitate self-management of people with COPD in developing countries, where access to healthcare can be challenging.

Chronic obstructive pulmonary disease and its treatment in the Russian Federation: Results of a cross-sectional assessment from the CORSAIR observational study

Abstract Up-to-date data on patients with chronic obstructive pulmonary disease (COPD) in the Russian Federation are necessary to improve medical care effectiveness.This article presents the results of the retrospective part and the cross-sectional assessment of the CORSAIR study, which aimed to assess the distribution of COPD patients in the Russian population by symptom severity and exacerbation risk as per GOLD (2020) classification groups A, B, C, D.Methods. The observational multicenter study CORSAIR included a cross-sectional assessment with data collection during the previous 12 months (retrospective part) and subsequent follow-up for 12 months (prospective part). Data from 704 patients obtained at 18 study sites from August 2021 to November 2022 are presented. At the first visit, the physician recorded medical history, clinical data on the disease course, and COPD therapy, assessed compliance of treatment with national guidelines, and determined whether treatment change was needed considering the predominant treatable trait (dyspnea or exacerbation).Results. Upon inclusion, most patients had severe COPD symptoms (mMRC score ≥ 2; САТ score ≥ 10) and severe and very severe airflow obstruction (GOLD III and GOLD IV; FEV1 &lt; 50% оf predicted). More than half of the patients had at least one moderate or severe COPD exacerbation within the previous 12 months. As per the GOLD (2020) classification, 57.2% of patients belonged to Group B (severe symptoms and low risk of exacerbations) and 30.3% to Group D (severe symptoms and high risk of exacerbations). 58.8% of patients received treatment that was not compliant with national clinical guidelines in force at the study initiation. 31.7% of patients had not COPD control. Blood eosinophil count was above 300 cells/μL in 15.1% of patients.Conclusion. In most cases, patients had severe COPD symptoms with frequent exacerbations, and the prescribed treatment did not comply with national clinical guidelines. These data will be analyzed alongside the prospective study results.

Degree of Airway Obstruction and Contributing Factors, Exploring Potential Mismatches and Pitfalls

BACKGROUND: The study investigates asthma, a chronic inflammatory respiratory condition that poses diagnostic challenges due to its variable symptoms, highlighting the importance of accurate documentation and interpretation. It aims to explore the demographic and clinical profiles of asthma patients, particularly focusing on the relationships among airway obstruction severity, spirometric measurements, atopic history, and family history to reveal the complex factors influencing asthma. AIMS: Employing a retrospective descriptive-analytic design, the research analyzes medical records of 107 patients treated at the Outpatient Installation of the Lung Polyclinic at Wlingi General Hospital in Blitar Regency from 2021 to 2022. The analysis incorporates descriptive statistics for demographic and clinical variables alongside Spearman correlation tests. METHOD: Results indicate a significant prevalence of smoking history among asthma patients, with 22.4% being active smokers and 52.3% passive smokers; however, no significant correlation with asthma control was found. Environmental risk factors such as dust and cold air were common but did not consistently correlate with asthma exacerbations. Spirometric analysis revealed a significant relationship between airway obstruction severity and parameters like FEV1, FVC, FEV1/FVC, PEF, FEF 25, FEF 50, and FEF 75, emphasizing the link between airflow obstruction and reduced lung function. Furthermore, no significant correlation was observed between stable asthma diagnosis and atopic or family history, suggesting that asthma control is influenced by various complex factors. CONCLUSION: Our research reveals critical pitfalls in the current understanding of asthma, advocating for a comprehensive evaluation of all contributing factors to enhance diagnostic accuracy and treatment efficacy. Recognizing these complexities is essential for improving asthma management and ensuring better health outcomes for patients.

Expiratory flow limitation development index (ELDI): a novel method of assessing respiratory mechanics in COPD

BackgroundExpiratory flow limitation (EFL) can be detected using oscillometric reactance and is associated with a worse clinical presentation in chronic obstructive pulmonary disease (COPD). Reactance can show negative swings upon exhalation, which may develop at different rates between patients. We propose a new method to quantify the rate of EFL development; the EFL Development Index (ELDI).MethodsA retrospective analysis of data from 124 COPD patients was performed. Data included lung function tests, Impulse Oscillometry (IOS), St Georges Respiratory Questionnaire (SGRQ), modified Medical Research Council (mMRC) scale and COPD Assessment Test (CAT) score. Fifty four patients had repeat data after 6 months. Twenty two patients had data recorded after 5 days of treatment with long acting bronchodilator therapy. EDLI was calculated as the mean expiratory reactance divided by the minimum expiratory reactance.ResultsThe mean ELDI was used to categorise patients with rapid onset of EFL (> 0.63; n = 29) or gradual onset (≤ 0.63; n = 34). Those with rapid development had worse airflow obstruction, lower quality of life scores, and greater resting hyperinflation, compared to those with gradual development. In patients with EFL, ELDI correlated with symptoms scores, airflow obstruction, lung volumes and gas diffusion. Both EFL and ELDI were stable over 6 months. EFL and EDLI improved with bronchodilator treatment.ConclusionsCOPD patients with rapid EFL development (determined by ELDI) had worse clinical characteristics than those with gradual EFL development. The rate of EFL development appears to be associated with clinical and physiological characteristics.

Debunking the GAMLSS Myth: Simplicity Reigns in Pulmonary Function Diagnostics

RationaleCurrent technical standards advocate using Generalized, Additive Models of Location, Scale, and Shape (GAMLSS) for lung function reference equations. These equations are complicated and require supplementary spline tables. Objective(1) To demonstrate that segmented (piecewise) linear regression (SLR) yields similar prediction accuracies as GAMLSS in pulmonary function diagnostics. (2) To determine the agreement between both SLR and GAMLSS. MethodsThe NHANES 2007-2012 database was utilized to construct spirometric reference equations for FEV1, FVC, and FEV1/FVC using both SLR and GAMLSS modeling techniques. K-fold cross-validation was used to provide the 95% confidence interval (CI) of the root-mean-square error (RMSE) as indicators of prediction accuracy. Additionally, agreement was assessed between the two modeling techniques in classifying spirometric patterns (standard, airflow obstruction, restrictive, or mixed disorder) using an unweighted kappa statistic. ResultsThe RMSE values for FEV1, FVC, and FEV1/FVC and correlation coefficients between predicted values and test data were similar between the two techniques. Agreement in classifying spirometric patterns between the two techniques ranged from 0.78 to 0.80 (95% CI). ConclusionsThe findings suggest that simple linear regression for FEV1/FVC and SLR for FEV1 and FVC offer prediction accuracies on par with GAMLSS while being more straightforward, parsimonious, and accessible to a broader audience in the field of pulmonary function diagnostics.

New Classifications of COPD Severity Based on Impulse Oscillometry: A SAIO Grade Base on ECOPD Cohort in China

BackgroundRecently, the severity of chronic obstructive pulmonary disease (COPD) can also be assessed by impulse oscillometry (IOS). This study aimed to explore a new classification of severity of COPD based on IOS and associations with acute exacerbations (AE) in patients with COPD. MethodsThe data of our study were based on the baseline and 2-year follow-up data of a prospective cohort in China. COPD was defined as post-bronchodilation FEV1/FVC <0.70. A new severity classification (staging of airflow obstruction by IOS, SAIO) was evaluated based on IOS parameters (R5, R5–R20, and X5 z-scores). We quantified using the weighted Bangdiwala B for agreement of severities of COPD between IOS parameters and FEV1%pred. The differences among SAIO stages were performed in symptom scores and imaging using analysis of covariance, and in the AE using negative binomial regression. ResultsOverall, 833 patients with COPD were included in this study. The weighted Bangdiwala B of R5, R5–R20, X5 z-scores, and FEV1%pred for evaluating agreement of the severity of COPD was 0.68, 0.70 and 0.83, respectively. The SAIO classifications system identified a greater number of adults with stage III–IV disease. SAIO provided significant discrimination between the stage I and stage III, IV for symptom scores, emphysema, and air trapping. SAIO provided significant discrimination between the stage I and other stages for AE. ConclusionsThe SAIO classifications provide discrimination between the stage I and stage III, IV for symptom scores, emphysema, air trapping, and AE, similar to the GOLD classifications. Trial registrationChinese Clinical Trial Registry, ChiCTR1900024643. Registered on 19 July, 2019.