FEV1/forced Vital Capacity Research Articles

Assessment of Metabolic Syndrome in Patients with Chronic Obstructive Pulmonary Disease: A 6-Month Follow-Up Study.

The association between chronic obstructive pulmonary disease (COPD) and metabolic syndrome (MetS) is a common one, with long-term therapeutic and prognostic impact. In view of the high pulmonary and cardiovascular morbidity and mortality, self-management contributes to decreasing the risk of an acute cardiac event or pulmonary decompensation. We conducted a prospective cohort study on 100 patients admitted to Iasi Clinical Rehabilitation Hospital who were divided into two groups according to the presence (67 patients) or absence (33 patients) of MetS. All patients benefited from multidisciplinary counseling sessions on their active role in improving modifiable cardiovascular risk factors and thus increasing quality of life. The aim of this study was to examine the impact of metabolic syndrome on lung function and the role of self-management in a 6-month follow-up period. The demographic, anthropometric, cardiovascular risk factors, and respiratory function were analyzed at baseline and at 6 months. The presence of MetS was associated with higher fasting blood glucose (p = 0.004) and triglycerides (p = 0.003) but not with higher levels of interleukins or TNF-alpha. At the 6-month follow-up, abdominal circumference, forced expiratory volume in one second (FEV1), dyspnea severity, and blood pressure values improved in male patients with COPD. Systolic and diastolic blood pressure decreased in the COPD group as a whole, but especially in male patients with and without associated MetS. BMI was positively correlated with FEV1 (r = 0.389, p = 0.001) and the FEV1/forced vital capacity (FVC) ratio (r = 0.508, p < 0.001) in all COPD patients and in the MetS subgroup. In the COPD group as a whole. the six-minute walk test (6MWT) results (m) were positively correlated with FEV1 and FVC. The correlation remained significant for FVC in COPD patients with and without MetS. An increase in BMI by one unit led to an increase in TG values by 3.358 mg/dL, and the presence of metabolic syndrome led to an increase in TG values by 17.433 mg/dL. In our study, MetS is a common comorbidity in patients with COPD and is associated with higher BMI, fasting glucose, and triglycerides but not with the inflammatory parameters. A mixed pulmonary-cardiovascular rehabilitation intervention leads to improvement in various parameters in both female and male COPD patients.

Similarities of metabolomic disturbances in prematurity-associated obstructive lung disease to chronic obstructive pulmonary disease

Prematurity-associated lung disease (PLD) is a long-term consequence of preterm-birth. Since the underlying mechanisms of PLD remain poorly characterised, we compared the urinary metabolome between recently described spirometry phenotypes of PLD. Preterm- and term-born children aged 7–12 years, from the Respiratory Health Outcomes in Neonates (RHiNO) cohort, underwent spirometry and urine collection. The urinary metabolome was analysed by gas chromatography time-of-flight mass spectrometry. Preterm-born children were classified into phenotypes of prematurity-associated obstructive lung disease (POLD, Forced expiratory volume in 1 s (FEV1) < lower limit of normal (LLN), FEV1/Forced Vital Capacity (FVC) < LLN), prematurity-associated preserved ratio impaired spirometry (pPRISm, FEV1 < LLN, FEV1/FVC ≥ LLN) and Preterm/Term controls (FEV1 ≥ LLN). Metabolite set enrichment analysis was used to link significantly altered metabolites between the groups with metabolic pathways. Univariable and multivariable linear regression models examined associations between early and current life factors and significantly altered metabolites of interest. Urine from 197 preterm- and 94 term-born children was analysed. 23 and 25 were classified into POLD and pPRISm groups respectively. Of 242 identified metabolites, 49 metabolites were significantly altered in the POLD group compared with Preterm controls. Decreased capric acid (log2 fold change − 0.23; p = 0.003), caprylic acid (− 0.18; 0.003) and ceratinic acid (− 0.64; 0.014) in the POLD group, when compared to preterm controls, were linked with reduced β-oxidation of very long chain fatty acids (p = 0.004). Reduced alanine (log2 fold change − 0.21; p = 0.046), glutamic acid (− 0.24; 0.023), and pyroglutamic acid (− 0.17; 0.035) were linked with decreased glutathione metabolism (p = 0.008). These metabolites remained significantly associated with POLD in multivariable models adjusting for early/current life factors. The pPRISm urinary metabolome was minimally changed when compared with preterm-born controls. When compared to term-born subjects, alterations in tryptophan metabolism were implicated (p = 0.01). The urinary metabolome in POLD showed significantly altered β-oxidation of fatty acids and glutathione metabolism, implying alterations in cellular metabolism and oxidative stress. Similar findings have been noted in adults with chronic obstructive pulmonary disease. Given the similarity of findings between the POLD group and those reported for COPD, the POLD group should be considered at future risk of developing COPD.

Relationship between symptoms and results on spirometry in adults seen in non-tertiary public health facilities presenting with preserved ratio impaired spirometry.

Preserved ratio impaired spirometry (PRISm), defined by reduced forced expiratory volume in 1 second (FEV1) without meeting criteria for airway obstruction, is often encountered in clinical practice. The management of this heterogeneous condition in individuals with chronic respiratory symptoms is challenging, especially under limited diagnostic resources. Since 2020, all consecutive patients referred for spirometry at our institution have been invited to participate in our registry. Other than spirometry, no other physiological lung function testing is available in this public health service. Therefore, we reviewed our databank with the aim of assessing: i) the proportion of symptomatic patients aged 18 years or older referred for spirometry presenting with PRISm; ii) the rate of inhaled medication used in this group, suggesting a referral diagnosis of obstructive airway disease (OAD); and iii) the relationship between symptoms and results on spirometry in PRISM compared to a group with obstruction matched by FEV1. To this end, the COPD Assessment Test (CAT) and the Asthma Control Test (ACT) were conjointly responded to by 1032 participants, irrespective of the clinical suspicion. We found that 22% had PRISM, of whom 200 were paired with obstruction by FEV1 (68±10% of predicted). The CAT and ACT results were well-correlated in both groups (r=-0.727 and -0,698, respectively; p<0.001) and used to measure symptoms. Participants in the final sample (n=400) were aged 62±13 years; 70% were ever smokers; and 55% reported household exposure to biomass smoke (at least 5 years). The CAT responses were in the range of moderate symptoms (17±9) and ACT borderline for uncontrolled symptoms (19±5). The main differences were higher body mass index (33±7 versus 29±7 kg/m2; p<0.001) and proportion of females (72 versus 49%; p<0.001) in PRISm compared to obstruction. This group had lower exposure to tobacco (65 versus 76% of ever-smokers) but greater exposure to biomass smoke (61 versus 49%) (p<0.05 for all). The rate of inhaled medication use was as high in PRISm as in obstruction (80%). Notwithstanding matched FEV1, we found less prominent signs of airway disease in PRISM: marginally reduced FEV1/forced vital capacity (FVC) ratio (94±8% of predicted); higher expiratory flow between 25% and 75% of vital capacity, despite presumed lower lung volumes (lower FVC); and lower rate of bronchial hyperresponsiveness. In an identical multivariate model, FEV1 predicted symptoms of obstruction only. In conclusion, these data raise suspicion of a substantial rate of misclassification of individuals with PRISM as having OAD in healthcare facilities with constraints on diagnostic resources.

The influence of CLEC5A on early macrophage-mediated inflammation in COPD progression

Chronic obstructive pulmonary disease (COPD) is a complex syndrome with poorly understood mechanisms driving its early progression (GOLD stages 1–2). Elucidating the genetic factors that influence early-stage COPD, particularly those related to airway inflammation and remodeling, is crucial. This study analyzed lung tissue sequencing data from patients with early-stage COPD (GSE47460) and smoke-exposed mice. We employed Weighted Gene Co-Expression Network Analysis (WGCNA) and machine learning to identify potentially pathogenic genes. Further analyses included single-cell sequencing from both mice and COPD patients to pinpoint gene expression in specific cell types. Cell–cell communication and pseudotemporal analyses were conducted, with findings validated in smoke-exposed mice. Additionally, Mendelian randomization (MR) was used to confirm the association between candidate genes and lung function/COPD. Finally, functional validation was performed in vitro using cell cultures. Machine learning analysis of 30 differentially expressed genes identified 8 key genes, with CLEC5A emerging as a potential pathogenic factor in early-stage COPD. Bioinformatics analyses suggested a role for CLEC5A in macrophage-mediated inflammation during COPD. Two-sample Mendelian randomization linked CLEC5A single nucleotide polymorphisms (SNPs) with Forced Expiratory Volume in One Second (FEV1), FEV1/Forced Vital Capacity (FVC) and early/later on COPD. In vitro, the knockdown of CLEC5A led to a reduction in inflammatory markers within macrophages. Our study identifies CLEC5A as a critical gene in early-stage COPD, contributing to its pathogenesis through pro-inflammatory mechanisms. This discovery offers valuable insights for developing early diagnosis and treatment strategies for COPD and highlights CLEC5A as a promising target for further investigation.

Flavonoid intakes, chronic obstructive pulmonary disease, adult asthma, and lung function: a cohort study in the UK Biobank

BackgroundGiven their antioxidative stress, anti-allergic, anti-inflammatory, and immune-modulating effects, flavonoids are hypothesized to play a role in preventing chronic obstructive pulmonary disease (COPD) and asthma. ObjectivesThis cohort study aimed to examine associations between flavonoid intake and COPD, asthma, and lung function. MethodsAmong 119,466 participants of the UK Biobank, median [interquartile range] age of 60 [53, 65] y, we estimated intakes of flavonoids, flavonoid-rich foods, and a flavodiet score from 24-h diet assessments. Prospective associations with both incident COPD and asthma and cross-sectional associations with measures of lung function [%predicted forced expiratory volume in 1s (FEV1); and FEV1/forced vital capacity (FVC)] were examined using multivariable-adjusted Cox proportional hazards and linear regression models, respectively. We investigated mediation by inflammation––represented by the INFLA score––and stratified analyses by smoking status. ResultsCompared with low intakes, moderate intakes of total flavonoids, flavonols, theaflavins + thearubigins, and flavanones, and moderate-to-high intakes of flavanol monomers, proanthocyanidins, anthocyanins, flavones, and the flavodiet score were associated with up to an 18% lower risk of incident COPD {e.g., [hazard ratio (95% confidence interval) for total flavonoids: 0.83 (0.75, 0.92)]} but not incident asthma. Furthermore, compared with low intakes, higher intakes of all flavonoid subclasses (except theaflavins + thearubigins), and the flavodiet score were associated with better percent predicted FEV1 baseline. Associations were most apparent in ever (current or former) smokers. Flavonoid intakes were inversely associated with the INFLA score, which appeared to mediate 11%–14% of the association between intakes of proanthocyanidins and flavones and incident COPD. ConclusionsModerate-to-high flavonoid intakes were associated with a lower risk of COPD and better lung function, particularly among ever smokers. Promoting intakes of healthy flavonoid-rich foods, namely, tea, apples, and berries, may improve respiratory health and lower COPD risk, particularly in individuals with a smoking history.

Walking or breathing: comparing the 6-minute walking distance test to the pulmonary function test for lung resection candidates.

Given the limited use of the 6-minute walking distance (6MWD) test as a replacement for standard tests in thoracic surgery, insufficient research exists on the prognostic value of this test, and further studies are necessary. This study aimed to investigate the correlation between pulmonary function tests (PFT) and the 6MWD test in lung resection patients. This cross-sectional study, conducted in 2021-2022, involved lung resection candidates referred to the thoracic surgery clinic. Demographic data, including age, sex, and body mass index (BMI), were collected, and pulmonary function tests and 6MWD tests were conducted for all patients. The sample size of the study was 31, and all patients received routine treatment during hospitalization. Of the 31 subjects included in the study, 16 were male (51.6%) and 15 (48.4%) were female. The mean age of the patients was 33.45±13.78 years. The median forced expiratory volume in one second (FEV1) and the mean ratio of FEV1/forced vital capacity (FVC) were 2.16 (1.49-2.85) liters and 81.80±7.34%, respectively. No significant correlation was found between the results of 6MWD and PFT, including FVC, FEV1, and FEV1/FVC ratio (P>0.05). The 6MWD test is a more economical and easily accessible test than PFT. However, this study found no correlation between the 6MWD test and spirometry parameters. Therefore, we suggest that surgeons should not rely on the 6MWD test as a predictive value for assessing respiratory function in lung resection candidates. The study's findings have important implications for clinical practice.

What constitutes an obstructive ventilatory impairment in a pediatric population? A study design.

There is no clear consensus as to what constitutes an obstructive ventilatory impairment (OVI) in pediatric populations. To determine the percentage of children/adolescents having an OVI among those addressed for spirometry after taking into account the definitions advanced by some international scholarly societies [British Columbia (BC), British thoracic-society (BTS), Canadian thoracic society (CTS), European respiratory society and American thoracic society (ERS-ATS), global initiative for asthma (GINA), Irish college of general practitioners (ICGP), national asthma council (NAC), national institute of clinical excellence (NICE), Société de pneumologie de langue française, Société pédiatrique de pneumologie et allergologie (SPLF-SP2A), and South African thoracic society (SATS)]. This bi-centric cross-sectional study involves two medical structures in Sousse/Tunisia, and will encompass children/adolescents aged 6-18 years. A medical questionnaire will be administered, clinical and anthropometric data will be collected, and the spirometric data will be measured by two spirometers. The following six definitions of OVI will be applied: i) GINA: Forced expiratory volume in 1 second (FEV1) < 80% and a FEV1/forced vital capacity (FVC) ≤ 0.90; ii) ICGP: FEV1/FVC < 0.70; iii) ERS-ATS or BTS or SATS or SPLF-SP2A or NAC: FEV1/FVC z-score < -1.645; iv) NICE: FEV1/FVC < 0.70 or FEV1/FVC z-score < -1.645; v) CTS: FEV1/FVC < 0.80 or a FEV1/FVC z-score < -1.645; and vi) ERS: "FEV1 z-score or FEV1/FVC z-score" < -1.645 or "FEV1 or FEV1/FVC" < 0.80. The percentage of children/adolescents having an OVI will significantly vary between the six definitions. The frequency of OVI in a pediatric population will depend on the definition chosen.

Neutrophil-to-Lymphocyte Ratio and Blood Eosinophil Levels As Inflammatory Indicators in Smoker and Non-smoker Young Adult Patients With Chronic Obstructive Pulmonary Disease at a Tertiary Care Hospital.

Background Inflammatory markers are elevated in chronic obstructive pulmonary disease (COPD) and can be quantified to detect severity, prognosis, mortality risk, and response to treatment. However, the estimation costs are high. The blood neutrophil-to-lymphocyte ratio (NLR) and eosinophil levels are emerging as biomarkers in COPD, yet there is a paucity of data. Aim and objectives This study was designed to elucidate the roles of the NLRand eosinophil levels in smokers and non-smokers with stable COPD male subjects, correlating them with lung functions. Materials and methods A prospective observational clinical study was conducted from January to June 2023, after receiving approval from the Institutional Ethics Committee, on 73 COPD patients aged 30-60 years who gave voluntary informed consent. Complete blood counts and spirometry were performed. Patients with a forced expiratory volume in one second(FEV1) % predicted <70% and an FEV1/forced vital capacity (FVC) % <70% based on the pulmonary function test (MIR Spirolab) were included. They were further divided into mild (n=10), moderate (n=27), severe (n=26), and very severe (n=10) categories as per the Global Initiative for Chronic Obstructive Lung Disease (GOLD) guidelines. Subjects were also categorized into smoker (n=45) and non-smoker (n=28) groups. The complete blood count was analyzed using an automated analyzer (Beckman Coulter). Analysis was also carried out with an NLR of more or less than three. A P-value of less than 0.05 was considered significant. Results Smokers constituted 61.65% (n=45) of the subjects, and non-smokers 38.35% (n=28). Among smokers, 17.78% had very severe airflow obstruction. In all COPD subjects (n=73), lymphocytes, eosinophils, and lung functions were lower in the group where the NLR was greater than three. NLR in smokers (3.52±1.43) was higher than in non-smokers (3.39±0.94). In non-smokers (n=28), blood eosinophils and lymphocytes were elevated. In smokers (n=45), blood neutrophils, monocytes, and basophils were increased. Smokers showed a non-significant increase in RBC, mean corpuscular volume (MCV), and mean corpuscular hemoglobin (MCH). Neutrophils, monocytes, eosinophils, and NLR increased with disease severity. NLR negatively correlated with FEV1 (r=-0.350, p=0.034) and positively with pack-years (r=0.546, p<0.001) in smokers. NLR negatively correlated with eosinophils, FVC, FEV1/FVC, and FEV1 % predicted. In all COPD subjects (n=73), NLR negatively correlated with blood eosinophils (r=-0.184, p=0.12), BMI, and lung functions. Conclusion NLR is elevated in COPD subjects and can serve as a marker of inflammation and a predictor of the risk and severity of airflow limitation. NLR correlates both positively and negatively with pack-years and lung functions, respectively.

Airway tree caliber heterogeneity and airflow obstruction among older adults.

Smaller mean airway tree caliber is associated with airflow obstruction and chronic obstructive pulmonary disease (COPD). We investigated whether airway tree caliber heterogeneity was associated with airflow obstruction and COPD. Two community-based cohorts (MESA Lung, CanCOLD) and a longitudinal case-control study of COPD (SPIROMICS) performed spirometry and computed tomography measurements of airway lumen diameters at standard anatomical locations (trachea-to-subsegments) and total lung volume. Percent-predicted airway lumen diameters were calculated using sex-specific reference equations accounting for age, height, and lung volume. The association of airway tree caliber heterogeneity, quantified as the standard deviation (SD) of percent-predicted airway lumen diameters, with baseline forced expired volume in 1-second (FEV1), FEV1/forced vital capacity (FEV1/FVC) and COPD, as well as longitudinal spirometry, were assessed using regression models adjusted for age, sex, height, race-ethnicity, and mean airway tree caliber. Among 2,505 MESA Lung participants (means ± SD age: 69 ± 9 yr; 53% female, mean airway tree caliber: 99 ± 10% predicted, airway tree caliber heterogeneity: 14 ± 5%; median follow-up: 6.1 yr), participants in the highest quartile of airway tree caliber heterogeneity exhibited lower FEV1 (adjusted mean difference: -125 mL, 95%CI: -171,-79), lower FEV1/FVC (adjusted mean difference: -0.01, 95%CI: -0.02,-0.01), and higher odds of COPD (adjusted odds ratio: 1.42, 95%CI: 1.01-2.02) when compared with the lowest quartile, whereas longitudinal changes in FEV1 and FEV1/FVC did not differ significantly. Observations in CanCOLD and SPIROMICS were consistent. Among older adults, airway tree caliber heterogeneity was associated with airflow obstruction and COPD at baseline but was not associated with longitudinal changes in spirometry.NEW & NOTEWORTHY In this study, by leveraging two community-based samples and a case-control study of heavy smokers, we show that among older adults, airway tree caliber heterogeneity quantified by CT is associated with airflow obstruction and COPD independent of age, sex, height, race-ethnicity, and dysanapsis. These observations suggest that airway tree caliber heterogeneity is a structural trait associated with low baseline lung function and normal decline trajectory that is relevant to COPD.

A POTENTIAL PARAMETER FOR ASSESSMENT OF EXERCISE CAPACITY IN PATIENTS WITH IDIOPATHIC PULMONARY DISEASE

https://youtu.be/_jIKpatUoGA BACKGROUND A 6-minute walk distance (6MWD) is widely used to assess functional exercise capacity in patients with cardiac or pulmonary disease and is known to hold strong prognostic utility. However, previous studies have shown that bodyweight negatively affects the predictive accuracy of the 6MWD. 6-minute walk work (6MWORK = 6MWD X bodyweight) has been shown to be more strongly associated with clinical markers in patients with chronic obstructive pulmonary disease (COPD), however, this has not been investigated in patients with idiopathic pulmonary fibrosis (IPF). This study aims to determine whether 6MWORK has a stronger correlation with clinical parameters compared to 6MWD in male patients with IPF. METHODS Clinical data was retrospectively analyzed from 22 male patients with IPF. Linear correlations between lung function, 6MWORK and 6MWD were performed. RESULTS There was a positive correlation between 6MWD and forced expiratory volume in the first second (FEV1) (r=0.488, p=0.021), while a strong positive correlation existed between 6MWORK and FEV1 (r=0.558, p=0.007). There was also a strong positive correlation between 6MWORK and FEV1/forced vital capacity (FVC) ratio (r=0.564, p=0.006), while there was no correlation between 6MWD and FEV1/FVC (r=0.320, p=0.146). Moreover, when performing a linear regression analysis, the FEV1 (β=0.411, p&amp;lt;0.033) and FEV1/FVC (β=0.420, p&amp;lt;0.030) were significant unique contributors to 6MWORK. The model was statistically significant check(R-square=0.47, F(2, 19)=8.31, p&amp;lt;0.003). CONCLUSION 6MWORK appears to be more closely associated with clinical parameters in male patients with IPF compared to 6MWD. 6MWORK may better characterize the clinical status of patients with IPF. Further study is needed to investigate the ability of 6MWORK to predict clinical endpoints.

COVID-19's Radiologic, Functional, and Serologic Consequences at 6-Month and 18-Month Follow-up: A Prospective Cohort Study.

We evaluated the radiologic, pulmonary functional, and antibody statuses of coronavirus disease 2019 (COVID-19) patients 6 and 18 months after discharge, comparing changes in status and focusing on risk factors for residual computed tomography (CT) abnormalities. This prospective cohort study was conducted on COVID-19 patients discharged between April 2020 and January 2021. Chest CT, pulmonary function testing (PFT), and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) immunoglobulin G (IgG) measurements were performed 6 and 18 months after discharge. We evaluated factors associated with residual CT abnormalities and the correlation between lesion volume in CT (lesionvolume), PFT, and IgG levels. This study included 68 and 42 participants evaluated 6 and 18 months, respectively, after hospitalizations for COVID-19. CT abnormalities were noted in 22 participants (32.4%) at 6 months and 13 participants (31.0%) at 18 months. Lesionvolume was significantly lower at 18 months than 6 months (P < 0.001). Patients with CT abnormalities at 6 months showed lower forced expiratory volume in 1 second (FEV1) and FEV1/forced vital capacity (FVC), and patients with CT abnormalities at 18 months exhibited lower FVC. FVC significantly improved between 6 and 18 months of follow-up (all P < 0.0001). SARS-CoV-2 IgG levels were significantly higher in patients with CT abnormalities at 6 and 18 months (P < 0.001). At 18-month follow-up assessments, age was associated with CT abnormalities (odds ratio, 1.17; 95% confidence interval, 1.03-1.32; P = 0.01), and lesionvolume showed a positive correlation with IgG level (r = 0.643, P < 0.001). At 18-month follow-up assessments, 31.0% of participants exhibited residual CT abnormalities. Age and higher SARS-CoV-2 IgG levels were significant predictors, and FVC was related to abnormal CT findings at 18 months. Lesionvolume and FVC improved between 6 and 18 months. Clinical Research Information Service Identifier: KCT0008573.

Pulmonary function characteristics in children with suspected asthma: implications for asthma diagnosis.

In children suspected of asthma, diagnosis is confirmed via variable expiratory airflow limitation. However, there is no single gold standard test for diagnosing asthma. This study aimed to evaluate the pulmonary function characteristics in children suspected of asthma without bronchodilator response (BDR) and bronchial hyperresponsiveness (BHR). We utilized two separate real-world retrospective observational cohorts of children who underwent both spirometry and bronchial provocation testing for asthma. Spirometry parameters were collected and compared between definite asthma, probable asthma, and non-asthma groups. The original cohort comprised 1199 children who visited the Severance Hospital (Seoul, Korea) between January 2017 and December 2019. The external cohort included 105 children who visited the Gangnam Severance Hospital between January 2019 and December 2019. Probable asthma accounted for 16.8% and 32.4% of the original and external cohorts, respectively. This group showed a significantly higher FeNO level and prevalence of allergic sensitization. Baseline forced expiratory volume in 1 second (FEV1), FEV1/forced vital capacity (FVC), forced expiratory flow at 25-75% of FVC (FEF25-75), and FEF75 showed stepwise decrements from non-asthma, probable asthma, to definite asthma patients (P < 0.001). The probable asthma group showed significantly higher odds of abnormal FEV1/FVC (OR, 2.24 [95%CI, 1.43-3.52])and FEF25-75 (2.05 [1.13-3.73]) than the non-asthma group and lower odds of abnormal FEV1(0.05 [0.01-0.19]),FEV1 /FVC (0.27 [0.18-0.41]), FEF25-75 (0.17 [0.11-0.28]), and FEF75 (0.14 [0.08-0.24]) compared to the definite asthma group. The external cohort was consistent with the original cohort. We show evidence of airway dysfunction in children for whom a high clinical suspicion of asthma exists without evidence of BDR and BHR. Repeated pulmonary function tests that closely monitor for subtle lung function impairments and active utilization of additional tests, such as allergic screening and FeNO, should be considered to close the gap in diagnosing asthma.

Impact of COVID-19 social distancing recommendations on pulmonary function, nutritional status, and morbidity in patients with cystic fibrosis.

To evaluate the impact of COVID-19 social distancing recommendations on nutritional status, pulmonary function, and morbidity in patients with cystic fibrosis (CF). A retrospective cohort study including patients older than six years with a diagnosis of CF was performed. Demographic and clinical data, anthropometric measurements, pulmonary function, days of antibiotic use, and length of hospital stay were recorded. Variables were recorded at three time points relative to the baseline for implementation of social distancing measures: T-1 (14 months before implementation), T0 (baseline), and T1 (14 months after implementation). Delta (Δ) was calculated for each period: Δ1 (pre-pandemic T0-T-1) and Δ2 (pandemic T1-T0). The study included 25 patients, with a mean age of 11.7±4.3 years. The mean forced expiratory volume in the first second (FEV1) was 85.6±23.6%, and body mass index (BMI) was 17.5±3.0 kg/m2. When comparing the two periods (Δ1 and Δ2), there was a significant increase in the FEV1/forced vital capacity (FVC) ratio (p=0.013) and in the forced expiratory flow between 25 and 75% of vital capacity (FEF25-75%) (p=0.037) in the pandemic period. There was also a significant reduction (p=0.005) in the use of antibiotics in the pandemic period compared with the pre-pandemic period. The Δ1 and Δ2 values did not differ significantly for BMI, FEV1, or length of hospital stay. COVID-19 social distancing recommendations had a positive impact (decrease) on morbidity (use of antibiotics) and small airway obstruction (FEF25-75%) in patients with CF.

A fully automated pipeline for the extraction of pectoralis muscle area from chest computed tomography scans.

Computed tomography (CT)-derived pectoralis muscle area (PMA) measurements are prognostic in people with or at-risk of COPD, but fully automated PMA extraction has yet to be developed. Our objective was to develop and validate a PMA extraction pipeline that can automatically: 1) identify the aortic arch slice; and 2) perform pectoralis segmentation at that slice. CT images from the Canadian Cohort of Obstructive Lung Disease (CanCOLD) study were used for pipeline development. Aorta atlases were used to automatically identify the slice containing the aortic arch by group-based registration. A deep learning model was trained to segment the PMA. The pipeline was evaluated in comparison to manual segmentation. An external dataset was used to evaluate generalisability. Model performance was assessed using the Dice-Sorensen coefficient (DSC) and PMA error. In total 90 participants were used for training (age 67.0±9.9 years; forced expiratory volume in 1 s (FEV1) 93±21% predicted; FEV1/forced vital capacity (FVC) 0.69±0.10; 47 men), and 32 for external testing (age 68.6±7.4 years; FEV1 65±17% predicted; FEV1/FVC 0.50±0.09; 16 men). Compared with manual segmentation, the deep learning model achieved a DSC of 0.94±0.02, 0.94±0.01 and 0.90±0.04 on the true aortic arch slice in the train, validation and external test sets, respectively. Automated aortic arch slice detection obtained distance errors of 1.2±1.3 mm and 1.6±1.5 mm on the train and test data, respectively. Fully automated PMA measurements were not different from manual segmentation (p>0.05). PMA measurements were different between people with and without COPD (p=0.01) and correlated with FEV1 % predicted (p<0.05). A fully automated CT PMA extraction pipeline was developed and validated for use in research and clinical practice.

Serum α-Klotho level, lung function, airflow obstruction and inflammatory markers in US adults.

α-Klotho is a pleiotropic protein that may have anti-oxidative and anti-inflammatory properties in the lung, but its role in airflow obstruction or lung function is largely unknown. This was a cross-sectional study of 6046 adults aged 40-79 years in the US National Health and Nutrition Examination Survey (NHANES) 2007-2012. We used multivariable logistic or linear regression to examine the relation between serum α-Klotho level and airflow obstruction, defined as forced expiratory volume in 1 s (FEV1) <80% of predicted and FEV1/forced vital capacity (FVC) ratio <0.70; FEV1, FVC and FEV1/FVC as percentage of predicted; and inflammatory markers in blood (white blood cell count, eosinophils, neutrophils and C-reactive protein (CRP)). α-Klotho levels in the second to fourth quartiles (Q2-Q4) were associated with significantly decreased odds of airflow obstruction (adjusted OR for Q2-Q4 versus lowest quartile (Q1) 0.54 (95% CI 0.35-0.81)) in never-smokers and ex-smokers with <10 pack-years of smoking, but not in current smokers or ex-smokers with ≥10 pack-years of smoking. In all participants, each unit increment in log10-transformed α-Klotho level was significantly associated with 5.0% higher FEV1 % pred and 3.7% higher FVC % pred. Higher α-Klotho was also associated with lower eosinophils, neutrophils and CRP in participants both with and without airflow obstruction. Higher serum α-Klotho is associated with lower inflammatory markers and higher lung function in adults with and without airflow obstruction, and with decreased odds of airflow obstruction in never-smokers and ex-smokers with <10 pack-years of smoking. Further studies are warranted to replicate our findings and evaluate underlying mechanisms.

Childhood Asthma Control Test and spirometry values in school-age children

Objective To determine the relationship between child and parent reports of asthma control using the Childhood Asthma Control Test (C-ACT) and spirometry. Methods This descriptive study included 648 children ages 5–11 years from a school-based asthma program. Not well-controlled asthma was defined as forced expiratory volume in 1 s (FEV1) and by FEV1/forced vital capacity (FVC) of 80% predicted or lower. Sensitivity and specificity of C-ACT scores for low FEV1 and FEV1/FVC levels were calculated. Logistic regression was used to obtain the area under the receiver operating characteristic curve (AUC) for C-ACT score categories by FEV1 level. Results Mean child age was 8.2 years, mean C-ACT score was 20.3 (SD = 3.96), mean FEV1 was 94.3% (SD = 17.1), and mean FEV1/FVC was 81.3 (SD = 8.5). Children with an FEV1 of 80% or less had significantly lower C-ACT scores than those with an FEV1 > 80% (p = .023, t = −2.015, df = 167); 95% CI [. −1.79 to −0.018]). The sensitivity and specificity of a C-ACT score of 19 or less for an FEV1 of 80% predicted or lower were 44.9 and 66.4%. With a C-ACT score of 22 or less, sensitivity and specificity for low FEV1 were 67.7 and 30.9%. The AUC for a C-ACT score of 19 or less and FEV1 of 80% or lower was .444 while the AUC was higher at .507 for a CACT score of 22 or less. Conclusion The C-ACT is a useful screen but spirometry should be performed in children with persistent symptoms to assess current asthma control.

Evaluation of the Double-Tracer Gas Single-Breath Washout Test in a Pediatric Field Study

The early life origins of chronic pulmonary diseases are thought to arise in peripheral small airways. Predictors of ventilation inhomogeneity, a proxy of peripheral airway function, are understudied in schoolchildren. Is the double-tracer gas single-breath washout (DTG-SBW) measurement feasible in a pediatric field study setting? What are the predictors of the DTG-SBW-derived ventilation inhomogeneity estimate in unselected schoolchildren? In this prospective cross-sectional field study, a mobile lung function testing unit visited participating schools in Switzerland. We applied DTG-SBW, fraction of exhaled nitric oxide (Feno), and spirometry measurements. The DTG-SBW is based on tidal inhalation of helium and sulfur-hexafluoride, and the phase III slope (SIIIHe-SF6) is derived. We assessed feasibility, repeatability, and associations of SIIIHe-SF6 with the potential predictors of anthropometrics, presence of wheeze (ie, parental report of one or more episode of wheeze in the prior year), Feno, FEV1, and FEV1/FVC. In 1,782 children, 5,223 DTG-SBW trials were obtained. The DTG-SBW was acceptable in 1,449 children (81.3%); the coefficient of variation was 39.8%. SIIIHe-SF6 was independently but weakly positively associated with age and BMI. In 276 children (21.2%), wheeze was reported. SIIIHe-SF6 was higher by 0.049 g.mol.L-1 in children with wheeze compared with those without and remained associated with wheeze after adjusting for age and BMI in a multivariable linear regression model. SIIIHe-SF6 was not associated with Feno, FEV1, and FEV1/FVC. The DTG-SBW is feasible in a pediatric field study setting. On the population level, age, body composition, and wheeze are independent predictors of peripheral airway function in unselected schoolchildren. The variation of the DTG-SBW possibly constrains its current applicability on the individual level. ClinicalTrials.gov; No.: NCT03659838; URL: www. gov.

Etiology and clinical characteristics of a non-cystic fibrosis bronchiectasis cohort in a middle eastern population

BackgroundBronchiectasis is a widely prevalent airway disease characterized by airway dilatation and recurrent infections, that can lead to respiratory failure in severe cases. The etiology of bronchiectasis varies geographically, but there is a lack of published data examining its etiology specifically within the Middle Eastern population.MethodsWe conducted a retrospective analysis of our bronchiectasis patient registry, extracting clinical and demographic characteristics from electronic medical records. Quantitative variables were presented as the median and interquartile range (IQR), while categorical variables were expressed as numbers and percentages. Statistical comparisons for continuous characteristics were performed using the t-test, and significance was determined by a p-value less than 0.05.ResultsIn total we analysed 260 records (63% female, 37% male), with median age of 58 years (interquartile range (IQR) 38–71), Body Mass Index (BMI) 25.8(IQR 22–30), forced expiratory volume in the first second (FEV1) %predicted 65 (IQR 43–79) and FEV1/forced vital capacity (FVC) 0.76 (0.67–0.86). Sixty-five cases (25%) were post-infectious in aetiology (excluding post-TB – n:27 10.4%). Forty-eight (18.5%) patients were labelled idiopathic, while Primary Ciliary Dyskinesia (PCD) accounted for 23 (8.8%) cases. Pseudomonas aeruginosa was the most common colonizing organism (32.7%), followed by Haemophilus influenzae (9.2%) and Methicillin-Sensitive Staphylococcus aureus(6.9%). At the time of review, 11 patients had died (median age, FEV %predicted, and bronchiectasis severity index (BSI) 59 years, 38% and 15.5 respectively), all due to respiratory failure, and as expected, all were classed severe on BSI. The BSI score was available for 109 patients, of which 31(28%) were classed mild, 29(27%) were moderate, and 49 (45%) were classed severe. The median BSI score was 8 (IQR 4–11). On dividing the patients according to obstructive vs. restrictive spirometry, we found that patients with FEV1/FVC < 0.70 had significantly higher BSI (10.1 vs. 6.9, p-value < 0.001) and that 8 out of the 11 deceased patients had FEV1/FVC < 70%.ConclusionsIn our study, post-infectious, idiopathic, and PCD were identified as the most common etiologies of bronchiectasis. Additionally, patients with obstructive spirometry appeared to have a worse prognosis compared to those with restrictive spirometry.

Associations between GrimAge acceleration and pulmonary function in the Coronary Artery Risk Development in Young Adults (CARDIA) study.

Background: Theobjective of this research wasto determine whether pulmonary function is associated with epigenetic aging (GrimAge) and whether GrimAge predicts emphysema. Methods: This prospective study examined 1042 participants enrolled as part of a community-based longitudinal cohort. Thecross-sectional associations betweenpulmonary function and GrimAge, measured at study year (Y) 20 (participant ages 40-45 years), and prospective associations with emphysema at Y25were examined. Results: At Y20, forced expiratory volume in 1 s (FEV1)and FEV1/forced vital capacity (FVC) were negatively associated with GrimAge; for Y0-Y10 cumulative measures, only theFEV1/FVC ratio was associated with GrimAge at Y15 and Y20. Emphysema at Y25 was associated with GrimAge at Y15 and Y20. Conclusion: Pulmonary function was associated with GrimAge during early and mid-life; GrimAge partially mediated the association between pulmonary function and emphysema.

Systemic Markers of Lung Function and Forced Expiratory Volume in 1 Second Decline across Diverse Cohorts.

Rationale: Chronic obstructive pulmonary disease (COPD) is a complex disease characterized by airway obstruction and accelerated lung function decline. Our understanding of systemic protein biomarkers associated with COPD remains incomplete. Objectives: To determine what proteins and pathways are associated with impaired pulmonary function in a diverse population. Methods: We studied 6,722 participants across six cohort studies with both aptamer-based proteomic and spirometry data (4,566 predominantly White participants in a discovery analysis and 2,156 African American cohort participants in a validation). In linear regression models, we examined protein associations with baseline forced expiratory volume in 1 second (FEV1) and FEV1/forced vital capacity (FVC). In linear mixed effects models, we investigated the associations of baseline protein levels with rate of FEV1 decline (ml/yr) in 2,777 participants with up to 7 years of follow-up spirometry. Results: We identified 254 proteins associated with FEV1 in our discovery analyses, with 80 proteins validated in the Jackson Heart Study. Novel validated protein associations include kallistatin serine protease inhibitor, growth differentiation factor 2, and tumor necrosis factor-like weak inducer of apoptosis (discovery β = 0.0561, Q = 4.05 × 10-10; β = 0.0421, Q = 1.12 × 10-3; and β = 0.0358, Q = 1.67 × 10-3, respectively). In longitudinal analyses within cohorts with follow-up spirometry, we identified 15 proteins associated with FEV1 decline (Q < 0.05), including elafin leukocyte elastase inhibitor and mucin-associated TFF2 (trefoil factor 2; β = -4.3 ml/yr, Q = 0.049; β = -6.1 ml/yr, Q = 0.032, respectively). Pathways and processes highlighted by our study include aberrant extracellular matrix remodeling, enhanced innate immune response, dysregulation of angiogenesis, and coagulation. Conclusions: In this study, we identify and validate novel biomarkers and pathways associated with lung function traits in a racially diverse population. In addition, we identify novel protein markers associated with FEV1 decline. Several protein findings are supported by previously reported genetic signals, highlighting the plausibility of certain biologic pathways. These novel proteins might represent markers for risk stratification, as well as novel molecular targets for treatment of COPD.