Respiratory Research
○ Springer Science and Business Media LLC
Preprints posted in the last 90 days, ranked by how well they match Respiratory Research's content profile, based on 19 papers previously published here. The average preprint has a 0.02% match score for this journal, so anything above that is already an above-average fit.
Haddan, S.; Waqas, A.; Rasool, G.; Schabath, M. B.
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Background: Our group previously reported that lung cancer (LC) screening history results and subsequent timing of diagnosis are associated with significant differences in survival outcomes. As a follow-up study, we sought to develop novel personalized risk models that considered screening history for incidence cancers, interval LCs, and prevalence LCs. Methods: Using data from the CT-arm of the NLST, four independent case-control analyses were conducted to develop parsimonious risk models. Controls (n=26,038) were those never diagnosed with LC. The four LC case groups were 270 prevalence LCs, 44 interval LCs, 206 screen-detected LCs (SDLCs) that had a baseline positive screen, and 164 SDLCs that had a baseline negative screen. For each case-control analysis, univariable analyses identified statistically significant covariates from 48 variables and then significant covariates were included into a stepwise backward selection approach to identify a model with the most informative covariates. Results: For prevalence LCs, the model (AUC=0.711) included age, pack-years smoked, BMI, smoking status, smoking onset age, personal history of cancer, family history of LC, alcohol consumption, and milling occupation. For interval LCs, the model (AUC=0.734) included age, smoking status, smoking onset age, cigar smoking, marital status, and asbestos occupation. For baseline positive SDLCs, the model (AUC=0.685) included age, pack-years smoked, BMI, emphysema, chemicals/plastics exposure, and milling occupation. For baseline negative SDLCs, the model (AUC=0.701) included age, pack-years smoked, BMI, smoking status, emphysema, sarcoidosis, and sandblasting occupation. Conclusions: Besides smoking and age, which are inclusion criteria for screening, these models identified other important risk factors which could be used to provide personalized LC risk assessment and screening management.
Verbanck, S.; Hughes, M.; Demolder, F.; Wellekens, S.; Vincken, S.; Vanderhelst, E.; Hanon, S.
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The ERS/ATS22 interpretative flowchart classifies diffusing capacity (DLco) into 5 scenarios with associated pathophysiology, and has not been tested on large patient groups. We aimed to obtain a more layered DLco interpretation, by interrogating DLco components Kco and VA, and by estimating lung inflation during the DLco test to identify the presence of restriction, which crucially impacts Kco interpretation. By assessing a "low VA" against lung inflation, a novel 9-scenario DLco classification with associated pathophysiology can be obtained. Lung patients from a tertiary center were classified according to the ERS/ATS22 chart and the novel 9-scenario one. Besides a control group of healthy subjects (n=303), disease groups under study were the following : asthma (n=1615), COPD (n=1338), CF (n=108), extrapulmonary restriction (n=122), ILD (n=98), post-COVID (n=193). Except for COPD, the prevalence of "normal DLco" (ERS/ATS22) was generally greater than that of "normal VA and normal Kco" (9-scenario); this discrepancy was most marked in CF (81% vs 56%) and in extrapulmonary restriction (57% vs 37%). With the novel 9-scenario chart, patients from very different diagnostic groups with a "low DLco" due to emphysema, bronchial disease, interstitial damage or incomplete expansion got classified across distinct scenarios, whereas ERS/ATS22 just grouped them together. In conclusion, when "low VA" is evaluated against lung inflation, a differentiation of DLco interpretation can be obtained in various patient groups involving obstruction and/or restriction. This approach can be readily implemented in clinical practice.
Palani, P. T.; Raut, S.; Sethi, P.; Gopalakrishnan, R. K.; Meena, V. P.; Sinha, S.; Wig, N.; Ray, A.
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BackgroundBronchiectasis is a debilitating respiratory condition characterized by chronic cough with expectoration of thick sputum. It accounts for significant morbidity and mortality, especially when associated with exacerbations. Assessing the health-related quality of life (HR-QoL) of patients with bronchiectasis is important to ascertain the impact of the disease on day-to-day life, as well as to gauge the effect of targeted interventions. Conventionally used methods for assessing HR-QoL such as the St. Georges Respiratory Questionnaire (SGRQ) are time-consuming and have limitations in day-to-day application. The Bronchiectasis Health Questionnaire (BHQ) is a novel, compact tool used for assessing the HR-QoL, and has been validated for use in Korean and Turkish populations. MethodsWe attempted to develop and validate the Hindi version of the Bronchiectasis Health Questionnaire (BHQ) in Indian adults with bronchiectasis. We assessed the correlation between the Hindi BHQ (H-BHQ) scores and other measures of lung health including the Hindi version of the COPD Assessment Tool (H-CAT), pulmonary function tests and the bronchiectasis severity index (BSI). In addition, we assessed the correlation between the H-BHQ scores and the number of exacerbations and hospital admissions in the previous year. ResultsA total of 145 subjects with bronchiectasis were included. The mean ({+/-} SD) H-BHQ total score was 49.10 {+/-} 10.3. The H-BHQ score correlated well with the H-CAT score (Correlation coefficient -0.6534, p value < 0.0001) and the mMRC scale (Correlation coefficient of -0.4459,p value < 0.0001). The H-BHQ score also had a moderate correlation with the number of exacerbations and low correlation with hospital admissions in the previous year, with correlation coefficients of -0.4193 (p < 0.0001) and -0.3030 (p < 0.0001), respectively. The correlation between the H-BHQ and the Bronchiectasis Severity Index (BSI) score was weak (Correlation coefficient of -0.3012, p value < 0.01). ConclusionThe H-BHQ offers a simple and convenient method to assess the HR-QoL in patients with bronchiectasis, and correlates well with other measures of respiratory health, including the H-CAT, the mMRC score and the number of exacerbations and hospital admissions in the previous year.
Trabadelo, H.
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BackgroundProgressive pulmonary fibrosis carries poor prognosis despite availability of antifibrotics. Current progression criteria rely on functional decline (FVC [≥]10% decline over 6-12 months), which detects disease worsening after significant structural damage. Previous quantitative CT (qCT) methods using fixed Hounsfield unit (HU) thresholds or volume-only measurements have shown inconsistent sensitivity for early progression. We hypothesized that a hybrid approach combining HU thresholding with Z-score normalization would detect qualitative progression (tissue densification) before quantitative territorial expansion. MethodsWe developed a novel hybrid CT analysis method integrating: (1) HU threshold-based fibrosis detection (>-600 HU), (2) Z-score normalization for severity stratification (mild Z=1-2, moderate Z=2-3, severe Z[≥]3), and (3) five clinical progression criteria including qualitative worsening ({Delta}Z-score [≥]0.5). The method was validated in two ILD patients with serial CT at short intervals (3.5 and 10 months). Automated lung segmentation, fibrosis quantification, and clinical decision support were implemented in Python (scikit-image, SimpleITK, NumPy). ResultsIn the index case (progressive COPD-fibrosis overlap, 3.5-month interval), traditional volume-based analysis showed minimal change (+1 mL, +2%), below significance threshold. However, the hybrid method detected significant qualitative progression: Z-score increased from 2.35 to 2.87 (+0.52 SD, p<0.05 criterion threshold), with emergence of 24 mL new severe fibrosis (Z[≥]3). This represented redistribution from mild/moderate to severe categories despite stable total volume. The qualitative progression criterion triggered clinical recommendation for antifibrotic consideration, which volume-only analysis would have missed. In a comparative case (10-month interval), massive quantitative progression (+136 mL, +191.5%) with moderate qualitative component ({Delta}Z +0.24) was detected, demonstrating method sensitivity across extreme progression patterns (pure densification vs dominant territorial expansion). ConclusionsThe hybrid HU-Z-score method overcomes critical limitations of previous qCT approaches by detecting qualitative fibrosis progression (tissue densification) independent of territorial expansion. This enables identification of "Phase 1 progression" (densification) at 3-6 month intervals, earlier than functional criteria (6-12 months) or traditional volumetric CT analysis. The method provides objective, standardized clinical decision support for antifibrotic therapy initiation, addressing a critical gap in progressive fibrosing ILD management. Prospective validation in larger cohorts is warranted to establish optimal {Delta}Z-score thresholds and evaluate impact on clinical outcomes.
Grudzinski, K. M.; Liu, G. Y.; Colangelo, L. A.; Selvan, K. C.; Putman, R.; Hunninghake, G. M.; San Jose Estepar, R.; Washko, G.; Kalhan, R.; Esposito, A. J.
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BackgroundInterstitial lung abnormalities (ILA) are radiologic findings of increased lung density or fibrosis in individuals without clinical interstitial lung disease (ILD) and are associated with increased mortality and progression to ILD. Understanding physiologic trajectories of lung function preceding ILA diagnosis may illuminate early mechanisms of lung injury. MethodsWe recruited participants from the Coronary Artery Risk Development in Young Adults (CARDIA) Lung Study, a prospective cohort of adults enrolled at ages 18-30 years and followed longitudinally for 25 years. Percent predicted forced vital capacity (ppFVC) was measured at five study visits over 20 years. Individual ppFVC trajectories were estimated using random coefficient models. Person-specific slopes were incorporated into logistic regression models to examine associations with visually detected ILA on chest CT at exam year 25. Models were adjusted for age, sex, race, body mass index, pack-years of smoking, and study center. ResultsAmong 3,136 participants with complete data, 57 (1.8%) had ILA at mean age 51 years. In univariable and multivariable models, individuals with ILA had greater cumulative decline in ppFVC over the 20 years preceding diagnosis. Each 10% absolute decline in ppFVC was associated with more than twice the odds of ILA (adjusted OR 2.21, 95% confidence interval 1.47-3.31, p = 0.0001). ConclusionsGreater longitudinal decline in FVC from early adulthood was strongly associated with the presence of ILA at midlife. These findings suggest that physiologic impairments precede radiologic evidence of subclinical parenchymal lung abnormalities, underscoring the potential of life course lung function trajectories to identify individuals at risk for developing ILD.
Sia, L. C.; Wong, C. K.; Sivakumar, D.; Chandran, D. M.; Yeoh, K. L.; Ling, S.-Y.; Leong, W. L.; Pang, Y.-K.
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Background and AimsThe prognosis of interstitial lung diseases (ILDs) other than idiopathic pulmonary fibrosis (IPF) has not been studied as extensively as IPF. This study aimed to evaluate baseline factors associated with mortality in non-IPF ILD, including demographic characteristics, respiratory function test (RFT), comorbidities, and ILD subtypes. MethodsThis retrospective cohort study analysed prospectively collected data of patients with non-IPF ILD at a single tertiary centre in Malaysia (2010-2023). Patients without baseline RFT or HRCT were excluded. Survival was assessed using Kaplan-Meier analysis, and mortality predictors were identified using Cox regression. ResultsThe mean age was 60 {+/-} 15 years, with a male-to-female ratio of 1:3. Indian ethnicity constituted the largest group (n = 109, 47.6%). The mean baseline forced vital capacity (FVC) was 53.3 {+/-} 21% predicted. An FVC <50% predicted, age [≥]50 years at diagnosis, specific ILD subtypes, and ethnicity were independently associated with mortality. Compared with Malays, both Chinese (hazard ratio [HR] 9.86, 95% confidence interval [CI] 1.27-76.89, p = 0.037) and Indians (HR 8.59, 95% CI 1.14-64.69, p = 0.001) were associated with a higher risk of death. Kaplan-Meier analysis demonstrated significant differences in survival across non-IPF ILD subtypes (log-rank p = 0.048), with hypersensitivity pneumonitis showing the poorest prognosis (mean survival 6.1 years). ConclusionEthnicity emerged as an independent prognostic factor for mortality in non-IPF ILD. The underlying mechanisms remain unclear and may reflect differences in genetic variation, cultural factors, or environmental exposures. Larger prospective studies are required to validate these findings.
Donastin, A.; Irawan, D.; Effendy, E.; Iryawan, R. D. A.; Nuari, N.; Oktaviana, B. M.; Yahya, D.; Muhammad, A. R.
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Background: Chronic Obstructive Pulmonary Disease (COPD) is the third leading cause of global mortality, with persistent lung inflammation contributing to disease progression. This inflammation is partly associated with reduced levels of histone deacetylase 2 (HDAC2). Previous studies suggest that Vitamin D may modulate HDAC2 levels. This study aimed to evaluate the effect of Vitamin D supplementation on HDAC2 expression in stable COPD patients. This experimental study aimed to evaluate the effect of vitamin D supplementation on HDAC2 expression in stable COPD patients at Jemursari Islamic Hospital. Methods: Five COPD patients received a daily dose of 5000 IU of Vitamin D for three months. Serum levels of 25(OH)D3 and HDAC2 were measured before and after the intervention. Results: Vitamin D supplementation resulted in a significant increase in both 25(OH)D and HDAC2 levels. Pulmonary function parameters showed an increasing trend, however, no statistically significant differences were observed. Conclusion: Vitamin D supplementation was associated with increased HDAC2 levels, suggesting a potential anti-inflammatory effect. However, no significant improvement in pulmonary function was observed. Further studies are needed to determine its clinical impact.
Bolig, T. C.; Grudzinski, K.; Shawabkeh, M.; Selvan, K. C.; Goodwin, R. J.; Olson, E.; Bemiss, B. C.; Parekh, N.; Savas, H.; Dematte, J. E.; Esposito, A. J.
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ObjectiveMyositis-associated interstitial lung disease (myositis-ILD) consists of two predominant radiologic patterns of lung injury--nonspecific interstitial pneumonia (NSIP) and organizing pneumonia (OP)--that oftentimes coexist. However, it remains unclear whether either is associated with clinical outcomes. We aimed to assess the therapeutic response in patients with NSIP-compared to those with OP-predominant myositis-ILD. MethodsThis retrospective, single-center cohort study recruited participants from the Northwestern University ILD Registry with a circulating myositis-associated antibody, ILD, and at least 6 months of follow-up while on immunomodulatory therapy during a 24-month observation period after diagnosis. Two thoracic radiologists determined the predominant radiologic pattern (NSIP or OP). The primary outcome was the absolute change in forced vital capacity (FVC) at 24 months post-diagnosis. Secondary outcomes included changes in the diffusing capacity of the lung for carbon monoxide (DLCO) and radiologic qualitative and quantitative measures of lung injury. ResultsForty-one participants were included in analyses. 71% had an OP-predominant while 29% had an NSIP-predominant radiologic pattern of lung injury. Both exposure cohorts had improvement in mean absolute FVC (OP cohort = +0.18L [p=0.005], NSIP cohort = +0.24L [p=0.07]) over the 24-month observation period. The OP (p<0.05) but not the NSIP cohort (p=0.20) had an increase in DLCO. The OP cohort demonstrated improvement in the qualitative assessment of follow-up imaging (p<0.05), driven by quantitative improvement in groundglass/consolidative opacities (p=0.006). A subset of participants demonstrated features of NSIP/OP overlap and had greater baseline radiologic severity of lung injury. ConclusionPatients with circulating myositis-associated antibodies and an OP-predominant pattern of lung injury may have a more favorable response to therapy than those with NSIP. Further studies are needed to validate our findings and delineate other features cognate with these associations. Significance and InnovationsO_LIRadiologic phenotyping may predict therapeutic response in myositis-ILD. This study demonstrates that an OP-predominant computed tomography (CT) pattern of lung injury is associated with greater improvement in lung function and radiologic signs of inflammation over 24 months on at least 6 months of immunomodulatory therapy compared with an NSIP-predominant pattern, suggesting that CT pattern may provide clinically meaningful prognostic information. C_LIO_LIFirst study to integrate blinded qualitative radiologic adjudication with quantitative CT scoring in myositis-ILD. By combining dual-radiologist review with Kazerooni quantitative scoring and longitudinal pulmonary function testing, this study offers a rigorous and multidimensional assessment of treatment response. C_LIO_LIExpands risk stratification beyond antibody-based toward imaging-based phenotyping strategies. In a heterogeneous population defined by diverse myositis-associated antibodies, this work introduces radiologic pattern as a practical and accessible framework for anticipating treatment responsiveness. C_LIO_LIProvides hypothesis-generating data for precision management in myositis-ILD. The findings support the concept that imaging-defined subgroups may exhibit differential therapeutic trajectories, laying groundwork for future multicenter studies integrating CT phenotype, antibody profile, and treatment strategy. C_LI
Majumder, S.; Biswas, P.; Chakrabortty, R.; Ahmed, S.; Rahman, M. A.
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BackgroundBronchiectasis in adults often goes undiagnosed following the routine assessment. Cystic Fibrosis (CF) is usually diagnosed during childhood, but some cases are identified in adulthood when disease is mild. High-resolution computed tomography (HRCT) of chest may offer structural information that can indicate CF as an underlying etiology. ObjectiveTo compare the HRCT features of adult patients with CF and non-CF bronchiectasis and to determine the radiologic features that may be suggestive of CF. MethodsThis retrospective, analytical, cross-sectional study was carried out in Bangladesh Medical University after IRB clearance. Total 130 adults (12 with CF and 118 with non-CF bronchiectasis) of both sexes, whose bronchiectasis was confirmed by chest HRCT were included. Imaging findings were assessed based on Reid morphological classification, anatomical distribution and extent of spread within the lungs, and their association was tested using chi-square test with statistical significance of p<0.05. ResultsCystic bronchiectasis was more common in CF than non-CF patients (83.3% vs 29.7; p<0.001). Mixed central-peripheral extension had been found a considerable associated with CF (66.7% vs. 42.4; p=0.034). There was no statistically significant difference in right lung lobar distribution (p=0.540) but combined upper and lower lobe involvement on the left side was more common in CF patients (54.5%) than non-CF patients (21.3) (p=0.054). ConclusionAdult CF had unique chest HRCT imaging characteristics when compared to non-CF bronchiectasis, especially cystic morphology and mixed extension. Identification of such features could help physician in the early diagnosis and selection of treatment strategy.
yin, h.; He, S.; Wu, Z.; Tan, W.; Du, F.; Yang, C.; Yu, H.
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Methods: Using Global Burden of Disease (GBD) data, we analyzed prevalence, incidence, mortality, and disability-adjusted life years (DALYs) rates across global and 21 GBD regions from 1990-2023. Joinpoint regression identified temporal trends, age-period-cohort models analyzed effect contributions, Das Gupta decomposition quantified demographic and epidemiological impacts, inequality indices assessed health equity, and Bayesian models projected 2024-2038 trends. Results: In 2023, the global number of children and adolescents with asthma reached 131 million, with an age-standardized prevalence rate (ASPR) of 1,789.9 per 100,000. From 1990 to 2023, the global ASPR and age-standardized incidence rate (ASIR) of asthma in children and adolescents showed an upward trend, while the age-standardized mortality rate (ASMR) and age-standardized disability-adjusted life years (DALYs) rate (ASDR) exhibited a downward trend. Among the 0-14 age group, the disease burden was greater in males than in females, whereas in the 15-19 age group, males had a lower disease burden than females. Projections indicate that over the next 15 years, the overall disease burden will continue to decline; however, female mortality rates and DALYs rates are projected to show an upward trend. Conclusions: The increasing prevalence and incidence rates, coupled with declining mortality and DALYs rates of asthma among children and adolescents globally, underscore the necessity for targeted public health interventions. These findings provide crucial insights for early diagnosis, treatment optimization, and global health policy formulation.
Stadler, S. V.; Stickley, L. C.; Bernasconi, E.; Guney-Ayra, S.; Trompette, A.; Piquilloud, L.; Funke-Chambour, M.; von Garnier, C.; Ubags, N. D.
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RationaleSevere SARS-CoV-2 infection induces disrupted oropharyngeal and gut microbiota during acute disease which may persist and contribute to the development of post-acute pulmonary sequelae. To date, it is unclear whether dysbiosis following severe disease is linked to long-term pulmonary function impairment. ObjectivesTo determine associations between oropharyngeal and gut microbiota composition with lung function after severe COVID-19. Methods16S and internal transcribed spacer (ITS) rRNA amplicon sequencing were performed on oropharyngeal (16S and ITS) and rectal (16S) swabs at 3-, 6- and 12-months post-hospitalisation from 83 subjects previously admitted to the ICU with severe COVID-19 (Swiss COVIDlung study, NCT04581135). Subjects underwent 1-3 follow-up visits during which lung function testing was performed to investigate associations with microbiota composition. Measurements and Main ResultsThe oropharyngeal microbiota of subjects having suffered from COVID-19-related-severe acute non-cardiogenic hypoxemic respiratory failure with bilateral lung infiltrates (AHRF-BLI) was characterized by decreased -diversity and the presence of differentially abundant taxa. Subjects who recovered in lung function (TLC, FVC, FEV1 and DLCO >Lower Limit of Normal) had a distinct oropharyngeal and gut microbiota composition compared to those whose lung function never recovered. Fungal analysis of oropharyngeal samples revealed the presence of three distinct clusters which were characterized by distinct lung-function associated bacterial-fungal co-occurrence. ConclusionsThis study provide first insights into the role of the airway and gut microbiota in the development of long-term pulmonary sequelae after severe SARS-CoV-2 infection, shedding the light on the potential of the microbiota for preventive and therapeutic strategies in severe COVID-19.
Oosterwegel, M. J.; Chatziioannoub, A. C.; Robinot, N.; Keski-Rahkonen, P.; McNeil, B. R.; Singh, R. R.; Miller, G. W.; Jeong, A.; Vogli, M.; Pickford, R.; Imboden, M.; Engelfriet, P. E.; Verschuren, W. M. M.; Peters, A.; Vermeulen, R.; Probst-Hensch, N.; Vlaanderen, J.; EXPANSE,
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ObjectiveChronic obstructive pulmonary disease (COPD) is a leading cause of death in the industrialized world. Although smoking, air pollution, and occupational exposures are well established risk factors, the molecular pathways linking environmental exposures and biological susceptibility to COPD remain incompletely understood. Untargeted metabolomics offers a unique opportunity to simultaneously capture internalized environmental chemicals and endogenous metabolic perturbations. However, large prospective studies integrating broad exposomic and metabolic screening prior to COPD onset are lacking. MethodsWe conducted a nested case-control study within three European population-based cohorts (Doetinchem Cohort Study, KORA, SAPALDIA) and analyzed 1473 prospectively collected plasma samples. COPD was defined by a pre-bronchodilation FEV1/FVC ratio below 0.7 at follow-up (4-16 years after blood sample collection). We applied complementary untargeted liquid- and gas chromatography high-resolution mass spectrometry (LC- and GC-HRMS), enabling extensive coverage of endogenous metabolism and exogenous environmental contaminants, including pesticides, plastic-related chemicals, and polycyclic aromatic hydrocarbons. Controls maintained normal lung function and were matched to cases on age, sex, follow-up time, and sample collection round. We performed separate conditional logistic regression models for each metabolomic feature, and used Mummichog for prediction of biological pathways involved. The false discovery rate (FDR) was controlled using the Benjamini-Hochberg procedure. Long-term measurement reliability was evaluated using intraclass correlation coefficients (ICCs) from repeat samples in the Doetinchem Cohort Study. ResultsIn total, thousands of metabolomic features were screened, including 724 annotated exogenous compounds, 13 endogenous metabolites, and 197 features that could be derived as both. Nicotine and cotinine intensity levels were statistically significantly associated with COPD incidence at an FDR of 10%, validating the analytical and epidemiologic framework. Lower levels of butyrylcarnitine were related to COPD onset in never-smokers. Beyond smoking-related markers, lower levels of butyrylcarnitine were associated with increased COPD risk among never-smokers, implicating altered mitochondrial fatty-acid metabolism as a potential early pathway independent of tobacco exposure. Although most screened environmental contaminants, including PAHs and pesticides, were not associated with COPD at stringent significance thresholds, restricting analyses to temporally stable metabolites identified the insecticide metabolite phenyl N-methylcarbamate as a predictor. ConclusionThis large-scale, prospective untargeted metabolomics study represents one of the most comprehensive assessments to date of both environmental and endogenous metabolic predictors of COPD. Our findings demonstrate the feasibility of exposome-wide molecular screening years before disease onset, identify butyrylcarnitine as a novel metabolic predictor in never-smokers, and highlight the importance of accounting for temporal variability in metabolomic epidemiology.
Walters, R.; Allen, M. B.; Scheen, H.; Beam, C.; Waldrip, Z.; Singule-Kollisch, M.; Varisco, A.; Williams, J. G.; De Luca, D.; Varisco, B. M.
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BackgroundIn patients requiring respiratory support, clinicians rely on physical exam, radiologic, laboratory, and ventilator-derived measures for the provision of sufficient support while minimizing ventilator and "work of breathing" induced lung injury. Point of care lung ultrasound (LUS) is a widely available tool in hospital and clinic environments. To date, LUS has not been used to evaluate lung strain. MethodsWe collected LUS images in four anesthetized, neuromuscularly blocked, and mechanically ventilated pigs being used for another experiment. A feature tracking tool was developed which tracked echo-bright lung structures in ten second clips obtained in triplicate of the right and left, upper and lower lung fields using tidal volumes of 4, 6, 8, 10, and 12 mL/kg. Pleural lines were manually drawn and a program for quantifying lung strain developed with assistance from Anthropic Claude Artificial Intelligence tool. Structures were identified in inspiratory and expiratory frames and tracked bidirectionally with median strain per frame used for calculations. ResultsTriplicate measures of lung ultrasound images in four pigs had a median coefficients of variation of 35% (23-47% IQR) and linear modeling of strain with tidal volumes of 4-12 mL/kg showed positive correlation with R2 value ranging from 0.89 to 0.97. Strain measurements were similar after bronchial administration of 1.5M hydrochloric acid. ConclusionsRegional lung strain quantification using LUS is a viable and potentially useful tool for respiratory support management.
Bottier, M.; Cant, E.; Perea, L.; Shuttleworth, M. K.; Fassad, M.; Mitchison, H. H.; Aliberti, S.; Goeminne, P. C.; Lind, H.; Viligorska, K.; Johnson, E. D.; New, J.; Long, M. B.; Altenburg, J.; Shteinberg, M.; Blasi, F.; Sibila, O.; Polverino, E.; Hogg, C.; Ollosson, S.; Loebinger, M. R.; Lorent, N.; Chalmers, J. D.; Shoemark, A.
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Mucociliary clearance is a key component of the pathophysiology of bronchiectasis but cilia function is poorly defined. This study aims to characterize nasal ciliary function in bronchiectasis and examine associations with disease severity, infection, inflammation and outcome. Adults with bronchiectasis and healthy volunteers were recruited to the international observational study EMBARC-BRIDGE. Individuals with a known diagnosis of Primary Ciliary Dyskinesia (PCD) were excluded. Nasal respiratory epithelium was sampled by brush biopsy. Ciliary function was assessed by high-speed video microscopy in primary samples and following re-differentiation in air-liquid interface (ALI) culture. Ciliary parameters (cilia length, angle, amplitude, clearance, frequency and ciliation) were quantified and compared with disease severity, microbiology, inflammation and future risk of exacerbations. 171 participants with bronchiectasis were recruited (54% female, age 68years (59-74)). Bronchiectasis nasal brushings showed greater epithelial disruption compared to healthy volunteers (p=0.0006). Six individuals with previously undiagnosed PCD were identified and excluded. In the remaining bronchiectasis cohort, ciliary beat frequency and length were similar to healthy controls. In contrast ciliary beat amplitude, angle, amplitude per second and clearance capacity, were significantly reduced (all p<0.001). These parameters were restored following ALI culture. Regenerated epithelia from bronchiectasis donors exhibited reduced ciliated area. Ciliary dysfunction was strongly associated with future risk of severe exacerbations. The upper airway epithelium is disrupted in bronchiectasis; ciliary movement is impaired and is associated with future risk of exacerbation. Ciliary dysmotility is reversible following ALI culture. This indicates that impaired ciliary function is secondary to the airway environment and therapeutically targetable.
Su, X.; Lin, L.; Yu, L.; Guo, Z.; Lin, M.; Zeng, G.; Chen, X.; Li, D.
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To explore the mechanism of Hsa_circ_0000629 adsorbing miR-212-5p/ nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) through sponge in bronchial asthma. Twenty BALB/C mice were randomly divided into a normal control group and an asthma group. Pathological changes in lung tissue were observed via HE staining. Human bronchial epithelial cells (16HBE) were transfected with Hsa_circ_0000629 overexpression group (Hsa_circ_0000629-over), Hsa_circ_0000629 siRNA (Hsa_circ_0000629-si), mimic NC, miR-212-5p mimic, inhibitor NC, miR-212-5p inhibitor, and LPS+Hsa_circ_0000629 si. LPS-induced asthmatic cell models (LPS group) and untransfected 16HBE cells (NC group) served as controls. qRT-PCR was used to measure Hsa_circ_0000629, miR-212-5p and NLRP3 expression. ELISA assessed interleukin 18 (IL-18), interleukin 1{beta} (IL-1{beta}), interleukin 6 (IL-6) and tumor necrosis factor - (TNF-) levels. Cell proliferation and the apoptosis were evaluated by EDU assay and flow cytometry, respectively. Western blot analyzed Cleaved-caspase 1, 3 and 9 proteins expression. Dual-luciferase assay verified the binding sites of Hsa_circ_0000629 to miR-212-5p and NLRP3 to miR-212-5p. HE staining revealed inflammatory cell infiltration, bronchial wall thickening, smooth muscle hyperplasia, and alveolar destruction in asthmatic mice. Compared with the controls, Hsa_circ_0000629 and NLRP3 expression were significantly increased, while miR-212-5p expression was decreased in asthmatic lung tissues. In 16HBE cells, Hsa_circ_0000629-over and LPS groups showed elevated Hsa_circ_0000629 and NLRP3 expression but reduced miR-212-5p levels. Silencing Hsa_circ_0000629 in LPS-treated cells (LPS+Hsa_circ_0000629-si) reversed these effects. Overexpression of miR-212-5p counteracted Hsa_circ_0000629-induced NLRP3 upregulation, while miR-212-5p inhibition enhanced NLRP3 expression. LPS exposure increased TNF-, IL-18, IL-6, and IL-1{beta} levels, reduced cell proliferation, and promoted apoptosis. These changes were attenuated by Hsa_circ_0000629 silencing or miR-212-5p overexpression. Western blot confirmed that Hsa_circ_0000629 overexpression upregulated Cleaved-Caspase 1, 3, and 9, whereas miR-212-5p mimic or Hsa_circ_0000629-si reversed this trend. Dual-luciferase assays demonstrated targeted interactions among Hsa_circ_0000629, miR-212-5p, and NLRP3. Interference with Hsa_circ_0000629 expression can alleviate LPS induced apoptosis in 16HBE cells and inhibit the expression of inflammatory factors by targeting the miR-212-5p/NLRP pathway, which may be a new target for the treatment of asthma.
Cheng, I.-H.; Lin, H.-E.; Lu, R. T.-C.; Soong, W.-J.; Yong, S.-B.; Lin, C.-H.
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BackgroundImpulse oscillometry is a noninvasive pulmonary function test performed during quiet breathing and requires minimal patient cooperation. It is useful for detecting small airway disease and provides increased sensitivity for diagnosing asthma in younger children who may have difficulty completing standard spirometry. Bronchodilator testing, a standard assessment of airflow obstruction reversibility, is recommended in patients with suspected asthma who present obstructive airflow patterns. ObjectiveTo evaluate impulse oscillometry parameters before and after bronchodilator administration across different age groups and to examine the relationship between age and airway resistance in patients with clinician-diagnosed asthma. MethodsThis retrospective study included patients with clinician-diagnosed asthma who demonstrated obstructive airflow patterns and a positive bronchodilator response. Participants were grouped by age: younger than 6 years, 6 to 20 years, and older than 20 years. Key impulse oscillometry parameters--airway resistance at 5 Hz, airway resistance at 20 Hz, the difference between these values, and resonance frequency--were collected and compared across groups. A positive bronchodilator response was defined as a reduction in airway resistance of more than 30% in individuals younger than 18 years and more than 40% in adults. ResultsA total of 225 patients (123 males and 102 females) were included, with a median age of 6 years. At baseline, the median airway resistance at 5 Hz was 175.34% of the reference value (95% CI, 171.66-178.62), and airway resistance at 20 Hz was 121.68% (95% CI, 118.73-127.12). The median difference between these values was 52.32% (95% CI, 49.89-57.14), and the median resonance frequency was 5.11 Hz (95% CI, 4.62-5.35). After bronchodilator administration, airway resistance at 5 Hz decreased to 123.56% (95% CI, 119.07-126.77), corresponding to a median reduction of 52.8% (95% CI, 49.48-56.08; P < 0.0001). Age demonstrated a moderate positive correlation with airway resistance at 20 Hz (r = 0.51, P < 0.001). ConclusionsProximal airway resistance increases with age among patients with asthma, suggesting age-related differences in airway inflammation. Impulse oscillometry combined with bronchodilator assessment provides a practical approach for evaluating airflow reversibility and enhances diagnostic accuracy in suspected asthma.
Patel, D.; D'Cruz, L.; Ahmed, W.; Chauhan, A.; Bakerly, N.; Grundy, S.; Trivedi, D. K.; Knight, S.
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Background Scalable, non invasive tools are critically needed to improve early lung cancer detection and optimize primary care referral pathways. We evaluated Inflammacheck, a point-of-care device utilizing exhaled breath condensate (EBC) H2O2 and physiological parameters with machine learning, for non-invasive lung cancer detection in a real-world screening population. Methods ExPeL study participants, from the UK Targeted Lung Health Check (TLHC) programme, included individuals with suspected lung cancer and low-risk ever-smoker controls. EBC was collected via Inflammacheck, measuring H2O2;, end-tidal CO2;, humidity, temperature, and exhalation flow rate. Multivariate analyses (PCA, LDA, Mahalanobis distance) assessed intrinsic group separation. SMOTE-balanced data trained supervised machine learning models (stacked and voting ensembles), which were then evaluated on held-out test sets. In parallel, untargeted LCMS metabolomics was performed to identify discriminatory molecular features. Results Analysing 34 participants with valid EBC data, 83% of cancer cases were early-stage (I or II), reflecting a screening population. Multivariate analysis clearly separated lung cancer and controls across PCA, LDA, and Mahalanobis mapping. The voting ensemble model achieved: Accuracy 85.7%, Sensitivity 80%, Specificity 100%, Precision (PPV) 100%, ROC AUC 0.90, MCC 0.73. Crucially, no false positives were identified. EBC variables revealed greater dispersion in cancer patients, reflecting physiological heterogeneity missed by univariate analysis. Untargeted metabolomics identified 2,132 features, with four key metabolites yielding an AUC of 0.969 for cancer discrimination. Discussion Inflammacheck effectively distinguishes early-stage lung cancer via a rapid, non-invasive breath test, findings which are highly relevant for primary care and screening triage, where non-specific symptoms and low prevalence pose challenges.
Cook, S. F.; Brouwer, A. F.; Taylor, J. M. G.; Cummings, K. M.; Arenberg, D. A.; Fleischer, N. L.; Meza, R.
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ImportanceChronic obstructive pulmonary disease (COPD) remains a leading cause of morbidity and mortality in the United States (US), largely driven by cigarette smoking and characterized by progressive lung injury. While e-cigarettes are promoted as a less harmful alternative to cigarette smoking, their long-term health effects, including the impact of prolonged use on COPD incidence among adults who have smoked, are not well understood. ObjectiveTo evaluate the prospective association between duration of e-cigarette use and incident COPD among US adults aged 40 years or older with a history of cigarette smoking, and to determine whether baseline respiratory symptoms modify this association. Design, Settings, and ParticipantsWe used data from Waves 4 to 7 (2017-2022) of the Population Assessment of Tobacco and Health (PATH) Study, a nationally representative US longitudinal cohort study. Our analysis included adults aged 40 years or older who currently or formerly smoked cigarettes. Main Outcomes and MeasuresThe outcome was incident, self-reported COPD diagnosis. The main exposure was the time-varying duration of e-cigarette use. Baseline functionally important respiratory symptoms were defined by a validated index. Multivariable models adjusted for demographics, COPD risk factors, and detailed tobacco use history, including cigarette smoking status, time since quitting, and pack-years. ResultsAmong 4,895 adults aged 40 year or older who currently or formerly smoked cigarettes, 408 reported an incident COPD diagnosis. Among individuals with baseline respiratory symptoms, longer e-cigarette use duration was associated with increased COPD risk (adjusted hazard ratio [AHR]: 1.28, 95% CI: 1.16, 1.40), whereas no significant association was observed among those without baseline respiratory symptoms (AHR: 1.01, 95% CI: 0.92, 1.12). Results were consistent after adjusting for cumulative cigarette exposure and other risk factors and remained robust across multiple sensitivity analyses. Conclusion and RelevanceProlonged e-cigarette use may increase COPD risk among individuals with pre-existing respiratory vulnerabilities. Although switching from combustible cigarettes remains an important harm reduction strategy, behavioral counseling and pharmacotherapy should be prioritized for those at high risk for COPD, with e-cigarette cessation support available to high-risk former smokers. Continued surveillance and research are warranted as e-cigarette products and use patterns evolve. Key PointsO_ST_ABSQuestionC_ST_ABSDoes longer e-cigarette use increase COPD risk in adults with a smoking history? FindingsIn this national cohort study of U.S. adults aged 40+ who currently or formerly smoked, e-cigarette duration was associated with higher self-reported COPD incidence among individuals with respiratory symptoms at baseline (adjusted hazard ratio [AHR] 1.28, 95% CI 1.16, 1.40) but not among those without symptoms (AHR 1.01, 95% CI 0.92, 1.12). MeaningProlonged e-cigarette use may increase COPD risk among individuals with respiratory vulnerabilities. While cigarette cessation should remain the priority, evidence-based e-cigarette cessation strategies are needed to prevent long-term use in this population.
Charalampopoulos, T.; Selvaraju, S. M.; Smith, I.; Cerrone, E.; Mohanraj, R.; Condliffe, R.; Elliot, C.; Hameed, A.; Hurdman, J.; Rothman, A. M. K.; Swift, A.; Kiely, D.; THOMPSON, A. A. R.
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IntroductionCardiopulmonary exercise testing (CPET) quantifies exercise limitation and helps differentiate cardiovascular dysfunction from deconditioning in patients with exertional dyspnoea. In mild pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH), traditional CPET oxygen delivery parameters may not adequately distinguish cardiac limitation. We evaluated whether oxygen pulse (O2 pulse) kinetics and the ratio of ventilation-carbon dioxide slope to peak oxygen uptake (VEVCO2/peakVO2) improve identification of cardiovascular limitation and prognostication. MethodsWe retrospectively analysed 289 consecutive patients referred for CPET. Patients were categorised into pre-capillary PH, no PH, or "unclassified" PH based on haemodynamics. O2 pulse slopes were calculated across exercise phases, and qualitative curve patterns were classified. VEVCO2/peakVO2 was derived from standard CPET parameters. Logistic regression assessed predictors of cardiac dysfunction (peak O2 pulse <65% predicted). Survival was evaluated using Kaplan-Meier and Cox regression analyses. ResultsPre-capillary PH patients demonstrated more impaired aerobic capacity and ventilatory efficiency than those without PH. Abnormal O2 pulse patterns (early plateauing or down-sloping) were associated with shallower slopes, lower peak O2 pulse, and greater chronotropic index. A work-phase O2 pulse slope < 0.40 identified impaired oxygen delivery but was not independently predictive in multivariable analysis. VEVCO2/peakVO2 independently predicted cardiac dysfunction (OR 3.9 [2.6-6.2], p < 0.001) and showed strong discrimination (AUC 0.83). VEVCO2/peakVO2 [≥] 2.7 independently predicted mortality (HR 13.6, 95% CI 3.8-48.5, p<0.001) outperforming peak O2 pulse and VE/VCO2 slope. ConclusionO2 pulse kinetics, particularly a work-phase slope < 0.40 and plateauing or decreasing trajectories, are associated with cardiac dysfunction in patients with pre-capillary PH. VEVCO2/peakVO2 appears to be a marker of cardiovascular limitation and mortality and may aid differentiation between cardiac dysfunction and deconditioning in this population when conventional CPET parameters are inconclusive.
Qiao, J.; Yao, K.; Zheng, S.; Chang, M.; Zhang, P.; Yang, Y.; Kong, Y.; Qiao, Y.; Chen, J.; Han, Z.; Hou, J.; Tan, N.; Wang, L.; He, P.; Fan, G.-c.; Sadayappan, S.; Jegga, A. G.; Jiang, L.; Feng, Y.
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BackgroundExtensive comorbidity between cardiovascular (CVD) and respiratory (RT) diseases is well-documented, yet the shared genetic mechanisms remain elusive. Genetic pleiotropy may play a pivotal role in understanding the intricate comorbidity patterns associated with cardiovascular and respiratory conditions. MethodsOur comprehensive analysis encompasses the largest available GWAS dataset of European ancestry covering six major CVDs (atrial fibrillation, coronary artery disease, venous thromboembolism, heart failure, peripheral arterial disease, and stroke) and four prevalent RTs (asthma, chronic obstructive pulmonary disease, idiopathic pulmonary fibrosis, and sleep apnea). Initially, we aimed to unveil the common genetic basis of major CVDs, through genome-wide and local genetic correlations and polygenic overlap. Subsequently, the shared genetic mechanisms between RTs and CVDs was investigated in terms of both horizontal and vertical pleiotropy. From a horizontal pleiotropy perspective, cross-trait analysis was utilized to identify pleiotropic genetic determinants including genomic loci, single nucleotide polymorphisms (SNPs), genes, biological pathways, and protein targets. From a vertical pleiotropic perspective, Mendelian randomization was employed to evaluate potential causal relationships between CVDs and RTs. ResultsOur study confirmed the significant existence of genetic correlations and overlaps between CVDs and RTs. Pleiotropy analysis under the composite null hypothesis identified 17,964 significant potential pleiotropic SNPs in 24 trait pairs, with 73 pleiotropic loci and 69 colocalized loci detected. Gene-based analysis revealed 59 candidate pleiotropic genes, highly enriched in unsaturated fatty acid biosynthetic processes and MHC class I-mediated antigen processing and presentation. Mendelian randomization analysis demonstrated a positive causal relationship only between chronic obstructive pulmonary disease and heart failure. Overall, the genetic basis between CVDs and RTs was inconsistent with vertical pleiotropy, suggesting the dramatic impact of horizontal pleiotropy. ConclusionsOur findings indicate widely distributed pleiotropic genetic determinants between RTs and CVDs across the genome. These results support a common genetic basis for RTs and CVDs and are important for intervention and therapeutic targets in comorbidities. Clinical PerspectiveO_ST_ABSWhat Is New?C_ST_ABSO_LIA common genetic underpinning for CVDs and RTs has been identified using a variety of approaches and further explained as a shared genetic mechanism mediated by pleiotropy. C_LIO_LIThe systematic atlas of horizontal pleiotropy addressed key questions about pleiotropic SNPs, genomic loci, genes, functional features, and protein targets contributing to comorbidity between CVDs and RTs. C_LIO_LIThe systematic atlas of vertical pleiotropy highlighted causal associations between CVDs and RTs beyond the observed correlations. C_LI What Are the Clinical Implications?This study may help to elucidate the shared genetic mechanism between respiratory and cardiovascular diseases and further prioritize shared drug targets between RTs and CVDs.