General considerations for lung function testing

Assessing sterility techniques in bronchodilator responsiveness testing by practicing allergists in North America

Background

The American Thoracic Society has published general guidelines for sterility when testing for bronchodilator responsiveness. However, the extent to which practicing allergists implement sterility measures is currently unknown.

Objective

This study aims to understand the adherence to the American Thoracic Society guidelines for sterility among practicing allergists.

Methods

In 2015, a questionnaire was approved and distributed by the American Academy of Allergy, Asthma & Immunology to all its members. The anonymous responses were recorded and tabulated after a 3-week period.

Results

Of the 6800 allergists who received surveys from the American Academy of Allergy, Asthma & Immunology members, 496 participated in the survey (response rate 7.3%). Using metered dose inhalers with a spacer and nebulizers were the most common bronchodilator administration techniques, as indicated by 59.35% and 58.52% of responses, respectively. Whereas 69.25% of the allergists considered their bronchodilator administration techniques to be sterile, 14.05% did not consider their administration technique to be sterile and 16.70% were unsure. For maintaining sterility, 38.75% of the respondents indicated using a new disposable attachment for reused inhalers, 18.71% indicated using a new inhaler for each patient, and 9.13% reported wiping inhalers with a cleaning agent.

Conclusions

When asked about the sterility of the techniques used by them, nearly one-third of the allergists either stated that the measures used by them were unsterile or stated that they were were unsure. To increase adherence to sterility measures among North American allergists, promoting guideline awareness and proposing updated guidelines focused on the most common bronchodilator administration techniques is essential.

Association of computed tomography-derived pectoralis muscle area and density with disease severity and respiratory symptoms in patients with chronic obstructive pulmonary disease: A case-control study

RATIONALE AND OBJECTIVES

Computed tomography (CT) is commonly used and offers an additional viewpoint for evaluating extrapulmonary symptoms, disease severity, and muscle atrophy. This study assessed whether the pectoralis muscle area (PMA) and pectoralis muscle density (PMD) are lower in patients with chronic obstructive pulmonary disease (COPD) than in healthy controls and elucidated their relationships with these variables.

MATERIALS AND METHODS

The participants were enrolled in the hospital outpatient clinic between October 2023 and May 2024. Information was obtained from questionnaires, lung function, and CT imaging findings. On full-inspiratory CT, the PMA and PMD were measured at the aortic arch level using predetermined attenuation ranges of -29 and 150 Hounsfield units. We observed lower PMA and PMD and evaluated their associations with lung function, respiratory symptoms, and CT imaging findings in patients with COPD.

RESULTS

Overall, 120 participants were enrolled at baseline (60 healthy controls and 60 patients with COPD). PMA and PMD were lower with progressive airflow limitation severity in those with COPD. The degree of emphysema and air trapping, as well as lung function, were correlated with PMA and PMD (P < 0.05), although not with the COPD Assessment Test or modified Medical Research Council scores (P > 0.05).

CONCLUSION

Participants with COPD had smaller PMA and PMD. These measurements were correlated with the severity of airflow limitation, lung function, emphysema, and air trapping, suggesting that these features of the pectoralis muscle obtained from CT are helpful in assessments of patients with COPD.

Effect of high-dose N-acetylcysteine on exacerbations and lung function in patients with mild-to-moderate COPD: a double-blind, parallel group, multicentre randomised clinical trial

Evidence for the treatment of patients with mild-to-moderate chronic obstructive pulmonary disease (COPD) is limited. The efficacy of N-acetylcysteine (an antioxidant and mucolytic agent) for patients with mild-to-moderate COPD is uncertain. In this multicentre, randomised, double-blind, placebo-controlled trial, we randomly assigned 968 patients with mild-to-moderate COPD to treatment with N-acetylcysteine (600 mg, twice daily) or matched placebo for two years. Eligible participants were 40-80 years of age and had mild-to-moderate COPD (forced expiratory volume in 1 second [FEV1] to forced vital capacity ratio <0.70 and an FEV1 ≥ 50% predicted value after bronchodilator use). The coprimary outcomes were the annual rate of total exacerbations and the between-group difference in the change from baseline to 24 months in FEV1 before bronchodilator use. COPD exacerbation was defined as the appearance or worsening of at least two major symptoms (cough, expectoration, purulent sputum, wheezing, or dyspnoea) persisting for at least 48 hours. Assessment of exacerbations was conducted every three months, and lung function was performed annually after enrolment. The difference between the N-acetylcysteine group and the placebo group in the annual rate of total exacerbation were not significant (0.65 vs. 0.72 per patient-year; relative risk [RR], 0.90; 95% confidence interval [CI], 0.80-1.02; P = 0.10). There was no significant difference in FEV1 before bronchodilator use at 24 months. Long-term treatment with high-dose N-acetylcysteine neither significantly reduced the annual rate of total exacerbations nor improved lung function in patients with mild-to-moderate COPD. Chinese Clinical Trial Registration: ChiCTR-IIR-17012604.

The Association Between Respiratory Functions, Pain Tolerance and Body Awareness in Obstructive Lung Diseases

PURPOSE

There are only a limited number of studies in the literature evaluating body awareness, pain perception, and the relationship between clinical parameters and respiratory functions in patients with obstructive lung disease (OLD) and compared with healthy individuals. Therefore, this study aimed to evaluate respiratory functions, pain tolerance, and body awareness in patients with OLD and compare these findings with those of healthy individuals.

METHODS

The study included 33 patients and 30 healthy individuals. The respiratory function (spirometer), respiratory muscle strength (mouth pressure device), endurance (threshold loading device), pain level and tolerance (short-form McGill Pain Questionnaire and algometer), posture, and body awareness (Body Awareness Questionnaire-BAQ) were evaluated.

RESULTS

The pain threshold and tolerance of the biceps, triceps, trapezius, and quadriceps muscles were significantly lower and BAQ scores were higher in patients with OLD compared with healthy individuals (p < .05). There was a significant relationship between FEV1 (%) and pain tolerance of the triceps (r = 0.371, p = .047) and gastrocnemius muscles (r = 0.419, p = .024); FVC (%) and pain threshold of the gastrocnemius (r = 0.413, p = .023), triceps muscles (r = 0.394, p = .034), and pain tolerance of the gastrocnemius muscle (r = 0.549, p = .002).

CONCLUSIONS

Patients with OLD have a marked increase in pain perception and body awareness levels and a decrease in pain threshold and tolerance compared with healthy controls. Future studies should assess the effectiveness of pain management interventions as a part of pulmonary rehabilitation for patients with chronic respiratory diseases.

CLINICAL IMPLICATIONS

Pain management is important for planning pulmonary rehabilitation programmes.

Chest wall muscle area, ventilatory efficiency and exercise capacity in systemic sclerosis

To investigate the potential contribution of chest wall muscle area (CWMA) to the ventilatory efficiency and exercise capacity in patients with Systemic Sclerosis (SSc) without interstitial lung disease (ILD). Forty-four consecutive SSc patients [F = 37, median age 53.5 years (IQR 43.5-58)] were examined using chest high-resolution computed tomography (HRCT), pulmonary function tests and cardiopulmonary exercise testing (CPET). The CWMA was evaluated at the level of the ninth thoracic vertebra on CT images by two independent evaluators blinded to the patient information. CPET parameters analyzed were maximum oxygen uptake (VO2 max) and VO2 at anaerobic threshold (VO2@AT); minute ventilation (VE); maximum tidal volume (VT). A statistically significant positive correlation was found between CWMA and maximum workload (r = 0.470, p < 0.01), VO2 max ml/min (r = 0.380, p < 0.01), VO2@AT (r = 0.343, p < 0.05), VE (r = 0.308, p < 0.05), VT (r = 0.410, p < 0.01) and VO2/heart rate (r = 0.399, p < 0.01). In multiple regression analysis, VO2 max (ml/min) was significantly associated with CWMA [β coefficient = 5.226 (95% CI 2.824, 7.628); p < 0.001], diffusing capacity for carbon monoxide (DLco) [β coefficient = 6.749 (95% CI 1.460, 12.039); p < 0.05] and body mass index (BMI) [β coefficient = 41.481 (95% CI 8.802, 74.161); p < 0.05]. In multiple regression analysis, maximum workload was significantly associated with CWMA [β coefficient = 0.490 (95% CI 0.289, 0.691); p < 0.001], DLco [β coefficient = 0.645 (95% CI 0.202, 1.088); p < 0.01] and BMI [β coefficient = 3.747 (95% CI 1.013, 6.842); p < 0.01]. In SSc-patients without ILD, CWMA represents an important variable in exercise capacity and can be evaluated by the mediastinal window available in the HRCT images required for lung disease staging.

Sarcopenia and sleep in individuals with chronic obstructive pulmonary disease

OBJECTIVE

To verify the relationship between sarcopenia and sleep in individuals with chronic obstructive pulmonary disease (COPD).

METHODS

Individuals with COPD were cross-sectionally assessed for lung function (spirometry), sleep (both subjectively [Pittsburgh Sleep Quality Index, PSQI] and objectively [Actiwatch sleep monitor]) and the presence of sarcopenia (handgrip strength by dynamometry). All tests were carried out in accordance with international standards.

RESULTS

Twenty-nine individuals with COPD were analyzed (16 women; 69 ± 7 years; BMI 27 ± 5 kg/m2; FEV1 59 ± 19% predicted). Upon division in groups according to the presence or absence of sarcopenia, individuals with sarcopenia (in comparison to those without sarcopenia) had shorter sleep time (81 [75-85] vs. 86 [81-90] %; p = 0.043), lower sleep efficiency (77 [69-83] vs. 85 [75-87] %; p = 0.038), longer time awake after sleep onset (92 [71-120] vs. 58 [47-83] minutes; p = 0.0012) and more marked sleep fragmentation, represented by a higher number of sleep blocks/night (46 [41-49] vs. 34 [26-48]; p = 0.018), higher number of awake blocks/night (45 [40-49] vs. 34 [26-48]; p = 0.018) and shorter duration of sleep blocks/night (9 [8-10] vs. 14 [8-58] minutes; p = 0.043). There was no statistical difference when comparing the PSQI variables between the groups. However, handgrip strength was negatively associated with PSQI components 2 [R= -0.51, p = 0.005] and 5 [R= -0.39, p = 0.037].

CONCLUSION

Individuals with COPD and sarcopenia (as measured by handgrip strength) have worse objectively measured sleep outcomes. This was not the case regarding a self-reported perception of worse sleep quality, although there was weak-to-moderate association between handgrip strength and subjective sleep.

Twice-Yearly Depemokimab in Severe Asthma with an Eosinophilic Phenotype

BACKGROUND

Depemokimab is an ultra-long-acting biologic therapy with enhanced binding affinity for interleukin-5 that may enable effective 6-month dosing intervals.

METHODS

In these phase 3A, randomized, placebo-controlled replicate trials, we evaluated the efficacy and safety of depemokimab in patients with severe asthma and an eosinophilic phenotype characterized by a high eosinophil count (≥300 cells per microliter in the previous 12 months or ≥150 cells per microliter at screening) and a history of exacerbations despite the receipt of medium- or high-dose inhaled glucocorticoids. Patients were randomly assigned in a 2:1 ratio to receive either depemokimab (at a dose of 100 mg subcutaneously) or placebo at weeks 0 and 26, plus standard care. The primary end point was the annualized rate of exacerbations at 52 weeks. Secondary end points, which were analyzed in a hierarchical manner to adjust for multiplicity, included the change from baseline in the score on the St. George's Respiratory Questionnaire (SGRQ), the forced expiratory volume in 1 second, and asthma symptom reports at 52 weeks.

RESULTS

Across the two trials, 792 patients underwent randomization and 762 were included in the full analysis; 502 were assigned to receive depemokimab and 260 to receive placebo. The annualized rate of exacerbations was 0.46 (95% confidence interval [CI]), 0.36 to 0.58) with depemokimab and 1.11 (95% CI, 0.86 to 1.43) with placebo (rate ratio, 0.42; 95% CI, 0.30 to 0.59; P<0.001) in SWIFT-1 and 0.56 (95% CI, 0.44 to 0.70) with depemokimab and 1.08 (95% CI, 0.83 to 1.41) with placebo (rate ratio, 0.52; 95% CI, 0.36 to 0.73; P<0.001) in SWIFT-2. No significant between-group difference in the change from baseline in the SGRQ score was observed in either trial, so no statistical inference was drawn on subsequent secondary end points. The proportion of patients with any adverse event was similar in the two groups in both trials.

CONCLUSIONS

Depemokimab reduced the annualized rate of exacerbations among patients with severe asthma with an eosinophilic phenotype. (Funded by GSK; SWIFT-1 and SWIFT-2 ClinicalTrials.gov numbers, NCT04719832 and NCT04718103.).

Investigating the relationship of trunk and postural control with pulmonary functions in subacute stroke patients

Stroke is a disease with high mortality and morbidity that not only causes weakness in the extremities, loss of balance, and disturbances in trunk and postural control, but also affects respiratory function. The aim of this study was to investigate the relationship between trunk and postural control and pulmonary function in subacute stroke patients. Herein, 32 volunteer patients who were diagnosed with hemiplegia by a competent physician after unilateral hemorrhagic or ischemic stroke and who met the inclusion criteria participated in the study. Functional independence of the participants was evaluated using the Modified Rankin Scale (mRS) and their cognitive function was assessed with the Standardized Mini Mental State Examination. Respiratory function was evaluated with spirometric measurements, inspiratory muscle strength was evaluated with intraoral pressure measurements, trunk control was evaluated using the Trunk Impairment Scale (TIS), postural control was evaluated using the Postural Assessment Scale for Stroke Patients (PASS-T), computerized postural sway evaluation, and static posture analysis. A significant correlation was found between the TIS scores and inspiratory muscle strength (p < 0.05). A significant correlation was also found between the PASS-T scores and inspiratory muscle strength and pulmonary function (p < 0.05). All of the COP parameters measured were significantly correlated with the PEF(L/s) and FEF25-75 (L/s) (p < 0.05). In conclusion, this study showed that trunk and postural control are associated with inspiratory muscle strength and pulmonary function. It is recommended that evaluation of trunk and postural control and respiratory functions, as well as exercise training to improve these parameters, should be included in rehabilitation programs for individuals with stroke.

Self-report underestimates the frequency of the acute respiratory exacerbations of COPD but is associated with BAL neutrophilia and lymphocytosis: an observational study

RATIONALE

Research studies typically quantify acute respiratory exacerbation episodes (AECOPD) among people with chronic obstructive pulmonary disease (COPD) based on self-report elicited by survey questionnaire. However, AECOPD quantification by self-report could be inaccurate, potentially rendering it an imprecise tool for identification of those with exacerbation tendency.

OBJECTIVE

Determine the agreement between self-reported and health records-documented quantification of AECOPD and their association with airway inflammation.

METHODS

We administered a questionnaire to elicit the incidence and severity of respiratory exacerbations in the three years preceding the survey among current or former heavy smokers with or without diagnosis of COPD. We then examined electronic health records (EHR) of those with COPD and those without (tobacco-exposed persons with preserved spirometry or TEPS) to determine whether the documentation of the three-year incidence of moderate to very severe respiratory exacerbations was consistent with self-report using Kappa Interrater statistic. A subgroup of participants also underwent bronchoalveolar lavage (BAL) to quantify their airway inflammatory cells. We further used multivariable regressions analysis to estimate the association between respiratory exacerbations and BAL inflammatory cell composition with adjustment for covariates including age, sex, height, weight, smoking status (current versus former) and burden (pack-years).

RESULTS

Overall, a total of 511 participants completed the questionnaire, from whom 487 had EHR available for review. Among the 222 participants with COPD (70 ± 7 years-old; 96% male; 70 ± 38 pack-years smoking; 42% current smoking), 57 (26%) reported having any moderate to very severe AECOPD (m/s-AECOPD) while 66 (30%) had EHR documentation of m/s-AECOPD. However, 42% of those with EHR-identified m/s-AECOPD had none by self-report, and 33% of those who reported m/s-AECOPD had none by EHR, suggesting only moderate agreement (Cohen's Kappa = 0.47 ± 0.07; P < 0.001). Nevertheless, self-reported and EHR-identified m/s-AECOPD events were both associated with higher BAL neutrophils (ß ± SEM: 3.0 ± 1.1 and 1.3 ± 0.5 per 10% neutrophil increase; P ≤ 0.018) and lymphocytes (0.9 ± 0.4 and 0.7 ± 0.3 per 10% lymphocyte increase; P ≤ 0.041). Exacerbation by either measure combined was associated with a larger estimated effect (3.7 ± 1.2 and 1.0 ± 0.5 per 10% increase in neutrophils and lymphocytes, respectively) but was not statistically significantly different compared to the self-report only approach. Among the 184 TEPS participants, there were fewer moderate to very severe respiratory exacerbations by self-report (n = 15 or 8%) or EHR-documentation (n = 9 or 5%), but a similar level of agreement as those with COPD was observed (Cohen's Kappa = 0.38 ± 0.07; P < 0.001).

DISCUSSION

While there is modest agreement between self-reported and EHR-identified m/s-AECOPD, events are missed by relying on either method alone. However, m/s-AECOPD quantified by self-report or health records is associated with BAL neutrophilia and lymphocytosis.

Prevalence and clinical relevance of comorbid pertussis infection in adult patients with asthma: A prospective, cross-sectional study

BACKGROUND

Viral or atypical bacterial respiratory infections are involved in the new development and the pathogenesis of asthma. Though an association between pertussis and asthma has been expected, few studies have reported it consistently. We assessed the prevalence and clinical relevance of pertussis infection in adult patients with asthma.

METHODS

In this prospective, cross-sectional study, newly referred, adult patients with asthma (n = 107) and with non-asthmatic subacute/chronic cough (n = 31) were enrolled. The prevalence of pertussis in patients with asthma and in those with non-asthmatic subacute/chronic cough was assessed. Next, the prevalence of newly diagnosed asthma was compared between asthmatic patients with and without pertussis. Finally, demographic characteristics of patients, blood test results, pulmonary function test results, and questionnaire scores were compared between the two patient groups.

RESULTS

The prevalence of pertussis infection was significantly higher in patients with asthma than in those with non-asthmatic subacute/chronic cough (36% vs 10%; P = 0.004). The prevalence of newly diagnosed asthma was significantly higher in asthmatic patients with pertussis than in those without (74.4% vs 50.0%; P = 0.014). The physical, psychological, and total scores of the Leicester Cough Questionnaire were significantly lower in asthmatic patients with pertussis than in those without (all P < 0.05). The acid-reflux, dyspeptic, and total scores of the Frequency Scale for Symptoms of Gastroesophageal Reflux Disease (GERD) (FSSG) were significantly higher in asthmatic patients with pertussis than in those without (all P ≤ 0.05). The FSSG acid-reflux score was negatively correlated with the cough-specific quality of life (QOL) score only in asthmatic patients with pertussis (rho = -0.68, P = 0.01).

CONCLUSIONS

The prevalence of pertussis infection was significantly higher in adult patients with asthma than in those with non-asthmatic subacute/chronic cough. In patients with asthma, comorbid pertussis infection may play a role in newly diagnosed asthma and may contribute to impaired cough-specific QOL partly due to worsening acid-reflux symptoms of GERD.

Physical activity, sedentary behaviour, and childhood asthma: a European collaborative analysis

OBJECTIVES

To investigate the associations of physical activity (PA) and sedentary behaviour in early childhood with asthma and reduced lung function in later childhood within a large collaborative study.

DESIGN

Pooling of longitudinal data from collaborating birth cohorts using meta-analysis of separate cohort-specific estimates and analysis of individual participant data of all cohorts combined.

SETTING

Children aged 0-18 years from 26 European birth cohorts.

PARTICIPANTS

136 071 individual children from 26 cohorts, with information on PA and/or sedentary behaviour in early childhood and asthma assessment in later childhood.

MAIN OUTCOME MEASURE

Questionnaire-based current asthma and lung function measured by spirometry (forced expiratory volume in 1 s (FEV1), FEV1/forced vital capacity) at age 6-18 years.

RESULTS

Questionnaire-based and accelerometry-based PA and sedentary behaviour at age 3-5 years was not associated with asthma at age 6-18 years (PA in hours/day adjusted OR 1.01, 95% CI 0.98 to 1.04; sedentary behaviour in hours/day adjusted OR 1.03, 95% CI 0.99 to 1.07). PA was not associated with lung function at any age. Analyses of sedentary behaviour and lung function showed inconsistent results.

CONCLUSIONS

Reduced PA and increased sedentary behaviour before 6 years of age were not associated with the presence of asthma later in childhood.

Co-exposure effects of urinary polycyclic aromatic hydrocarbons and metals on lung function: mediating role of systematic inflammation

BACKGROUND

Polycyclic aromatic hydrocarbons (PAHs) and metals were associated with decreased lung function, but co-exposure effects and underlying mechanism remained unknown.

METHODS

Among 1,123 adults from National Health and Nutrition Examination Survey 2011-2012, 10 urinary PAHs, 11 urinary metals, and peripheral white blood cell (WBC) count were determined, and 5 lung function indices were measured. Least absolute shrinkage and selection operator, Bayesian kernel machine regression, and quantile-based g-computation were used to estimate co-exposure effects on lung function. Mediation analysis was used to explore mediating role of WBC.

RESULTS

These models demonstrated that PAHs and metals were significantly associated with lung function impairment. Bayesian kernel machine regression models showed that comparing to all chemicals fixed at median level, forced expiratory volume in 1 s (FEV1)/forced vital capacity, peak expiratory flow, and forced expiratory flow between 25 and 75% decreased by 1.31% (95% CI: 0.72%, 1.91%), 231.62 (43.45, 419.78) mL/s, and 131.64 (37.54, 225.74) mL/s respectively, when all chemicals were at 75th percentile. In the quantile-based g-computation, each quartile increase in mixture was associated with 104.35 (95% CI: 40.67, 168.02) mL, 1.16% (2.11%, 22.40%), 294.90 (78.37, 511.43) mL/s, 168.44 (41.66, 295.22) mL/s decrease in the FEV1, FEV1/forced vital capacity, peak expiratory flow, and forced expiratory flow between 25% and 75%, respectively. 2-Hydroxyphenanthrene, 3-Hydroxyfluorene, and cadmium were leading contributors to the above associations. WBC mediated 8.22%-23.90% of association between PAHs and lung function.

CONCLUSIONS

Co-exposure of PAHs and metals impairs lung function, and WBC could partially mediate this relationship. Our findings elucidate co-exposure effects of environmental mixtures on respiratory health and underlying mechanisms, suggesting that focusing on highly prioritized toxicants would effectively attenuate adverse effects.

Severe Eosinophilic Asthma or Eosinophilic Granulomatosis With Polyangiitis: Potential Biomarkers for Novel Diagnostic Strategies

BACKGROUND

Severe eosinophilic asthma (SEA) may be the prodromal phase of eosinophilic granulomatosis with polyangiitis (EGPA). Nevertheless, few studies have tried to recognize EGPA in the early stages of the disease.

OBJECTIVE

To identify a panel of clinical and biological markers to detect which severe asthmatic patient might be considered in a prodromal phase of EGPA and crafting a strategy for diagnostic decision-making.

METHODS

A total of 30 patients with EGPA and 49 with SEA were enrolled. A complete pulmonary, ear, nose, and throat, and rheumatologic assessment were made. Blood (eosinophil count, eosinophilic cationic protein, IL-5, IL-4, total-IgE, IgG4, and antineutrophil cytoplasmic antibody), sputum (eosinophils count, periostin, IL-8, and granulocyte-monocyte colony-stimulating factor [GM-CSF]), and nasal smear (eosinophilia) biomarkers were assessed. Asthma Control Test, Short Form-36, SinoNasalOutcome Test-22, and Asthma Quality of Life Questionnaire were also used.

RESULTS

Patients with SEA had poorer asthma control (P < .001) and a higher level of sputum eosinophils (P < .002), whereas patients with EGPA reported higher levels of blood eosinophils in the past. Sputum GM-CSF was the only biomarker significantly increased in patients with EGPA compared with those with SEA (P < .0001). Among patients with SEA, those with some suggestive but not diagnostic criteria of EGPA, particularly tissue eosinophilic infiltrates, presented higher levels of sputum GM-CSF (P < .0005), blood, and sputum eosinophils (P < .0006 and P < .011) than the other patients.

CONCLUSION

Sputum GM-CSF and eosinophils might be useful biomarkers to support early diagnosis and treatment choices in patients with SEA, suspected of having EGPA.

Chronic Cough and Cerebellar Ataxia With Neuropathy and Bilateral Vestibular Areflexia Syndrome (CANVAS): Screening for Mutations in Replication Factor C Subunit 1 (RFC1)

INTRODUCTION

A common complaint in patients is chronic cough (CC), which may be refractory (RCC) or unexplained (UCC). Recent studies point, as a possible cause of CC, to the hereditary cerebellar ataxia with neuropathy and bilateral vestibular areflexia syndrome (CANVAS), with an estimated carrier prevalence of 1 in 20000.

AIM

In patients with CC, determine the prevalence of the biallelic (AAGGG)exp mutation in replication factor C subunit 1 (RFC1) responsible for CANVAS, test the usefulness of the Rydel-Seiffer fork test, and evaluate patient quality of life (QoL).

METHODS

Clinical and functional data were collected for the 33 included patients undergoing CC studies in our specialized unit. Performed were an etiological study of CC following European Respiratory Society recommendations, a genetic study of RFC1 mutations, and Rydel-Seiffer fork testing to detect possible peripheral vibratory sensitivity impairment. Administered to evaluate QoL were 4 questionnaires.

RESULTS

Prevalence of biallelic (AAGGG)exp in RFC1 was 6.1% (n=2) overall, increasing to 7.1% in the RCC subgroup, and to 33.3% in the Rydel-Seiffer fork altered results subgroup. Prevalence of monoallelic (AAGGG)exp in RFC1 was 18.2% (n=6) overall, rising to 50.0% (n=2) in the UCC subgroup.

CONCLUSION

Genetic screening for (AAGGG)exp in RFC1, and also use of the Rydel-Seiffer fork test, should be considered in specialized CC consultations for patients with RCC and UCC. Detecting possible CANVAS symptoms in CC studies would identify candidates for early genetic screening, of interest in reducing the disease burden for patients and health systems alike.

Clinical features and associated factors of impaired ventilatory efficiency: findings from the ECOPD study in China

BACKGROUND

Impaired ventilatory efficiency during exercise is a predictor of mortality in chronic obstructive pulmonary disease. However, little is known about the clinical features and associated factors of impaired ventilatory efficiency in China.

METHODS

We conducted a cross-sectional community-based study in China and collected demographic and clinical information, cardiopulmonary exercise testing, spirometry, and CT data. Impaired ventilatory efficiency was defined by a nadir ventilatory equivalent for CO2 production above the upper limit of normal. Multivariable linear and logistic regression models were used to explore the clinical features and associated factors of impaired ventilatory efficiency.

RESULTS

The final analyses included 941 subjects, 702 (74.6%) of whom had normal ventilatory efficiency and 239 (25.4%) had impaired ventilatory efficiency. Participants with impaired ventilatory efficiency had more chronic respiratory symptoms, poorer lung function and exercise capacity, and more severe emphysema (natural logarithm transformation of the low-attenuation area of the lung with attenuation values below -950 Hounsfield units, logLAA-950: 0.19±0.65 vs -0.28±0.63, p<0.001) and air trapping (logLAA-856: 1.03±0.65 vs 0.68±0.70, p<0.001) than those with normal ventilatory efficiency. Older age (60-69 years, OR 3.10 (95% CI 1.33 to 7.21), p=0.009 and 70-80 years, OR 6.48 (95% CI 2.56 to 16.43), p<0.001 vs 40-49 years) and smoking (former, OR 3.19 (95% CI 1.29 to 7.86), p=0.012; current, OR 4.27 (95% CI 1.78 to 10.24), p=0.001 vs never) were identified as high risk factors of impaired ventilatory efficiency.

CONCLUSIONS

Impaired ventilatory efficiency was associated with poorer respiratory characteristics. Longitudinal studies are warranted to explore the progression of individuals with impaired ventilatory efficiency.

Physical activity and body mass related to catch-up lung function growth in childhood: a population-based accelerated cohort study

OBJECTIVE

The existence of catch-up lung function growth and its predictors is uncertain. We aimed to identify lung function trajectories and their predictors in a population-based birth cohort.

METHODS

We applied group-based trajectory modelling to z-scores of forced expiratory volume in 1 second (zFEV1) and z-scores of forced vital capacity (zFVC) from 1151 children assessed at around 4, 7, 9, 10, 11, 14 and 18 years. Multinomial logistic regression models were used to test whether potential prenatal and postnatal predictors were associated with lung function trajectories.

RESULTS

We identified four lung function trajectories: a low (19% and 19% of the sample for zFEV1 and zFVC, respectively), normal (62% and 63%), and high trajectory (16% and 13%) running in parallel, and a catch-up trajectory (2% and 5%) with catch-up occurring between 4 and 10 years. Fewer child allergic diseases and higher body mass index z-score (zBMI) at 4 years were associated with the high and normal compared with the low trajectories, both for zFEV1 and zFVC. Increased children's physical activity during early childhood and higher zBMI at 4 years were associated with the catch-up compared with the low zFEV1 trajectory (relative risk ratios: 1.59 per physical activity category (1.03-2.46) and 1.47 per zBMI (0.97-2.23), respectively). No predictors were identified for zFVC catch-up growth.

CONCLUSION

We found three parallel-running and one catch-up zFEV1 and zFVC trajectories, and identified physical activity and body mass at 4 years as predictors of zFEV1 but not zFVC catch-up growth.

Deciphering Alveolo-Capillary Gas Transfer Disturbances in Patients Recovering from COVID-19 Lung Disease

Impaired lung gas exchange is commonly seen in patients with pulmonary involvement related to SARS-CoV-2 acute infection or post-acute COVID-19 syndrome (PACS). The primary aim of our study was to assess lung gas transfer, measuring the pulmonary diffusion capacity for nitric oxide (DLNO) and carbon monoxide (DLCO) in all COVID-19 patients. Our secondary aim was to decipher the respective roles of perturbed lung membrane conductance (DM) and reduced pulmonary capillary volume (VC) in patients with impaired lung gas exchange. From May to October 2020, we measured DLNO-DLCO in 118 patients during their post-COVID-19 period (4.6 months after infection) to decipher alveolo-capillary gas transfer disturbances. DLNO-DLCO measurement was also performed in 28 healthy non-smokers as controls. Patients were classified into three groups according to the severity (mild, moderate, and severe) of acute COVID-19 infection. Patients with mild COVID-19 had normal lung volumes and airways expiratory flows but impaired pulmonary gas exchange, as shown by the significant decreases in DLNO, DLCO, DM, and VC as compared with controls. VC was significantly impaired and the DLNO/DLCO ratio was increased in patients with moderate (n = 4, 11%) and severe COVID-19 (n = 23, 49%). Abnormal membrane conductance was also seen in all three groups of post-COVID-19 patients. These findings suggest a persistent alveolo-capillary gas transfer defect, implying not only reduced membrane conductance but also abnormal pulmonary vascular capacitance in all PACS patients, even those with a milder form of COVID-19 infection.

Home and school pollutant exposure, respiratory outcomes, and influence of historical redlining

BACKGROUND

The discriminatory and racist policy of historical redlining in the United States during the 1930s played a role in perpetuating contemporary environmental health disparities.

OBJECTIVE

Our objectives were to determine associations between home and school pollutant exposure (fine particulate matter [PM2.5], NO2) and respiratory outcomes (Composite Asthma Severity Index, lung function) among school-aged children with asthma and examine whether associations differed between children who resided and/or attended school in historically redlined compared to non-redlined neighborhoods.

METHODS

Children ages 6 to 17 with moderate-to-severe asthma (N = 240) from 9 US cities were included. Combined home and school exposure to PM2.5 and NO2 was calculated based on geospatially assessed monthly averaged outdoor pollutant concentrations. Repeated measures of Composite Asthma Severity Index and lung function were collected.

RESULTS

Overall, 37.5% of children resided and/or attended schools in historically redlined neighborhoods. Children in historically redlined neighborhoods had greater exposure to NO2 (median: 15.4 vs 12.1 parts per billion) and closer distance to a highway (median: 0.86 vs 1.23 km), compared to those in non-redlined neighborhoods (P < .01). Overall, PM2.5 was not associated with asthma severity or lung function. However, among children in redlined neighborhoods, higher PM2.5 was associated with worse asthma severity (P < .005). No association was observed between pollutants and lung function or asthma severity among children in non-redlined neighborhoods (P > .005).

CONCLUSIONS

Our findings highlight the significance of historical redlining and current environmental health disparities among school-aged children with asthma, specifically, the environmental injustice of PM2.5 exposure and its associations with respiratory health.

Efficacy of dupilumab for severe chronic rhinosinusitis with nasal polyps and asthma: A prospective study

BACKGROUND

Dupilumab exerts clinical effects, including improved sinus opacification, olfactory function, and quality of life, in patients with severe chronic rhinosinusitis with nasal polyps (CRSwNPs). Meanwhile, only a few studies have reported its effects on nasal airway resistance and olfactory function, particularly in the Japanese population. Predictors of response remain unclear.

OBJECTIVE

To assess the comprehensive efficacy and therapeutic response to dupilumab in patients with severe CRSwNP with comorbid asthma.

METHODS

In 16 adult patients with severe CRSwNP with comorbid asthma, the efficacy of 48-week dupilumab treatment, including olfactory function measured by a T&T olfactometer, nasal airway resistance measured by rhinomanometry, nasal polyp score, Lund-Mackay computed tomography score, and 22-item Sinonasal Outcome Test (SNOT-22), was assessed. Regarding asthma, the annualized rate of exacerbations, 7-item Asthma Control Questionnaire (ACQ-7), and spirometry were assessed. Treatment responsiveness was analyzed.

RESULTS

With 48-week dupilumab treatment, olfactory function, nasal airway resistance, nasal polyp score, Lund-Mackay computed tomography score, and SNOT-22 scores improved significantly. Regarding comorbid asthma, the annualized rate of exacerbations decreased, and ACQ-7 scores and lung function improved significantly. According to the European Position Paper on Rhinosinusitis and Nasal Polyps 2020/European Forum for Research and Education in Allergy and Airway Diseases criteria, 15 patients (94%) were moderate-to-excellent responders at 48 weeks of treatment. Patients with higher SNOT-22 scores, ACQ-7 scores, the rate of asthma exacerbations in the previous year, and blood eosinophil counts benefited more from the treatment.

CONCLUSION

Dupilumab improved upper and lower airway outcomes especially in patients with severe CRSwNP with comorbid, poorly controlled asthma.

TRIAL REGISTRATION

UMIN Clinical Trials Registry: UMIN000038669.

Reproducibility, validity, and reliability of the incremental step test for subjects with moderate to severe asthma

OBJECTIVE

We investigated the measurement properties of the incremental step test in subjects with moderate to severe asthma.

METHODS

Subjects with moderate to severe persistent asthma were recruited from a tertiary university hospital specializing in treating severe asthma. All subjects performed one cardiopulmonary exercise test (CPET) and two incremental step tests (IST) in random sequences. Pulmonary gas exchange was measured during all exercise tests. The measurement properties investigated were reliability by intraclass correlation coefficient (ICC), measurement error by the standard error of measurement and minimum detectable difference, construct validity by Pearson's correlation, and interpretability by the ceiling and floor effects.

RESULTS

Fifty subjects (38 females, mean [SD], age 43.7 [11.6] yr, % FEV1 70 [14.3], BMI 28.5 [5.3] kg/m2) completed the study. The peak oxygen uptake (peak VO2) for the CPET was 27.6 [±6.8] ml/kg/min, for the first IST was 22.3 [±5.3] ml/kg/min and for the second IST was 23.3 [±5.3] ml/kg/min. The IST presented excellent reliability (ICC=0.93, CI95% 0.88-0.96), very good measurement error (2.5%), and construct validity for peak VO2 measurement compared to the CPET (r = 0.85; p < 0.001) to assess exercise capacity in subjects with moderate to severe asthma, with appropriate ceiling (10%) and floor (0%) effects.

CONCLUSION

The IST presented excellent reliability and very good measurement error and validity to assess exercise capacity in subjects with moderate to severe asthma, without ceiling or floor effects.

Combining Spirometry and the ARISCAT Respiratory Risk Assessment Can Improve Postoperative Outcomes and Reduce Mortality Risk in Mexico

Introduction

Although a major goal of preoperative evaluation is to identify risk factors and improve postoperative outcomes, current clinical guidelines in Mexico indicate that preoperative spirometry should only be performed on patients with pulmonary disease. The aim of this study was to compare the incidence of postoperative complications (POC), mortality, and risk factors among adults who did or did not undergo preoperative spirometry, based on their Assess Respiratory Risk in Surgical Patients in Catalonia (ARISCAT) risk level.

Material and methods

An observational, retrospective and comparative study design was used to identify 2059 patients from the General Hospital of Mexico who had an ARISCAT assessment during 2013-2017. Patients were classified in two groups: ARISCAT with spirometry (n = 1306) and ARISCAT without spirometry (n = 753). Chi-square, Fisher's exact test and the Student's t-tests were used to compare groups. Logistic regression was used to identify factors associated with an increased risk of POC and mortality.

Results

In the ARISCAT with spirometry group, 11% of patients had POC, compared with 48% of patients in the ARISCAT without spirometry group. High-risk ARISCAT patients who did not receive spirometry had higher mortality (18%), than those who underwent spirometry (0.4%). Logistic regression results indicate that not performing preoperative spirometry increases the probability of POC and mortality.

Conclusions

Our findings suggest that the combined use of preoperative spirometry and ARISCAT is associated with reduced POC and mortality. Future clinical guidelines should recommend the use of preoperative spirometry for patients with a moderate or high ARISCAT level in Mexico.

Efficacy of dupilumab for airway hypersecretion and airway wall thickening in patients with moderate-to-severe asthma: A prospective, observational study

BACKGROUND

Dupilumab has clinical effects in patients with moderate-to-severe asthma. When considering interleukin (IL)-4 and IL-13 signaling, effects of dupilumab on airway mucus hypersecretion and airway remodeling are expected, but they have been reported in only a few short-term studies. Its efficacy for airway hyperresponsiveness (AHR) remains unknown. We comprehensively assessed the efficacy of dupilumab, especially for subjective and objective measures of airway mucus hypersecretion and airway dimensions in moderate-to-severe asthmatic patients.

METHODS

In 28 adult patients with moderate-to-severe uncontrolled asthma, the comprehensive efficacy of 48-week dupilumab treatment, including the Cough and Sputum Assessment Questionnaire (CASA-Q), radiological mucus scores and airway dimensions on computed tomography (CT), was assessed prospectively. Treatment responsiveness to dupilumab was analyzed.

RESULTS

With 48-week dupilumab treatment, all four cough and sputum domain scores of CASA-Q improved significantly. Radiological mucus scores and airway wall thickening on CT were significantly decreased. The decreases in mucus scores were significantly associated with improvements in Asthma Control Questionnaire scores, Asthma Quality of Life Questionnaire (AQLQ) overall scores, airway obstruction, and airway type 2 inflammation. When defined by > 0.5 improvement in AQLQ overall scores, 18 patients (64%) were identified as responders.

CONCLUSIONS

Dupilumab reversed subjective and objective measures of airway mucus hypersecretion and some aspects of airway remodeling in patients with moderate-to-severe uncontrolled asthma.

Lung ultrasound is a promising screening tool to rule out interstitial lung disease in patients with rheumatoid arthritis

BACKGROUND AND OBJECTIVE

It is still controversial how to screen for interstitial lung disease (ILD) in patients with rheumatoid arthritis (RA). We aimed to evaluate the performance of lung ultrasound (LUS) as a screening tool for RA-ILD and to compare it with the performance of chest auscultation, chest x-ray and pulmonary function tests (PFTs).

METHODS

Cross-sectional study of consecutive RA patients evaluated at a Rheumatology Clinic in Buenos Aires between January and December 2022. High-resolution computed tomography (HRCT) was the gold standard for diagnosing ILD and was performed within 30 days of the LUS, chest x-ray and PFTs. Investigators were blinded to HRCT results and patients' clinical data. LUS was performed by exploring 14 areas and was considered positive when the sum of B lines was ≥5. Performance for the diagnosis of ILD was reported for each diagnostic test.

RESULTS

One hundred and six patients were included; 87 (82%) were women. Median age was 60.9 (±9.5) years-old. A total of 32 (30.2%, 95% CI: 21.6%-39.9%) had ILD. The sensitivity and negative predictive value of LUS were 90.6% (95% CI 75.0%-98.0%) and 94.7% (95% CI 85.4%-98.9%), respectively. LUS performance was superior to that of the other evaluated diagnostic tests for screening ILD.

CONCLUSIONS

Given that the US is a low-cost point-of-care tool with a high negative predictive value, it is emerging as a valuable tool for ruling out ILD in patients with RA.

Contrast agent-free functional magnetic resonance imaging with matrix pencil decomposition to quantify abnormalities in lung perfusion and ventilation in patients with cystic fibrosis

Background

Previous studies showed that contrast-enhanced (CE) morpho-functional magnetic resonance imaging (MRI) detects abnormalities in lung morphology and perfusion in patients with cystic fibrosis (CF). Novel matrix pencil decomposition MRI (MP-MRI) enables quantification of lung perfusion and ventilation without intravenous contrast agent administration.

Objectives

To compare MP-MRI with established morpho-functional MRI and spirometry in patients with CF.

Methods

Thirty-nine clinically stable patients with CF (mean age 21.6 ± 10.7 years, range 8-45 years) prospectively underwent morpho-functional MRI including CE perfusion MRI, MP-MRI and spirometry. Two blinded chest radiologists assessed morpho-functional MRI and MP-MRI employing the validated chest MRI score. In addition, MP-MRI data were processed by automated software calculating perfusion defect percentage (QDP) and ventilation defect percentage (VDP).

Results

MP perfusion score and QDP correlated strongly with the CE perfusion score (both r = 0.81; p < 0.01). MP ventilation score and VDP showed strong inverse correlations with percent predicted FEV1 (r = -0.75 and r = -0.83; p < 0.01). The comparison of visual and automated parameters showed that both MP perfusion score and QDP, and MP ventilation score and VDP were strongly correlated (r = 0.74 and r = 0.78; both p < 0.01). Further, the MP perfusion score and MP ventilation score, as well as QDP and VDP were strongly correlated (r = 0.88 and r = 0.86; both p < 0.01).

Conclusion

MP-MRI detects abnormalities in lung perfusion and ventilation in patients with CF without intravenous or inhaled contrast agent application, and correlates strongly with the well-established CE perfusion MRI score and spirometry. Automated analysis of MP-MRI may serve as quantitative noninvasive outcome measure for diagnostic monitoring and clinical trials.

Bronchiectasis is associated with lower lung function in lung cancer screening participants

BACKGROUND AND OBJECTIVE

Bronchiectasis is a frequent incidental finding on chest computed tomography (CT), but its relevance in lung cancer screening is not fully understood. We investigated the association between bronchiectasis and respiratory symptoms, pulmonary function, and emphysema in lung cancer screening participants with and without chronic obstructive pulmonary disease (COPD).

METHODS

We included 3260 (ex-)smokers from the Dutch-Belgian lung cancer screening trial (NELSON). Bronchiectasis was scored by chest radiologists. The relationship with pulmonary function (FEV1%predicted, FEV1/FVC), respiratory complaints (cough, dyspnea, wheezing, mucus hypersecretion), and CT-quantified emphysema (15th percentile) was examined with independent t-tests and multivariate regression.

RESULTS

Bronchiectasis was present in 5.4% (n = 175/3260). There was no difference in prevalence between subjects with and without COPD (68/1121 [5.9%] vs. 109/2139 [5.1%]; p = .368). COPD subjects with bronchiectasis had a lower FEV1%predicted (76.2% vs. 85.0%; p < .001), lower FEV1/FVC (0.58 vs. 0.62; p < .001), and more emphysema (- 938 HU vs. - 930 HU; p = .001) than COPD subjects without bronchiectasis. In COPD subjects, bronchiectasis was independently associated with a lower FEV1%predicted (B =  - 7.7; CI [- 12.3, - 3.3]), lower FEV1/FVC (B =  - 2.5; CI [- 4.3, - 0.8]), more cough (OR 2.4; CI [1.3, 4.3]), more mucus hypersecretion (OR 1.8; CI [1.0, 3.1]) and more dyspnea (OR 2.3; CI [1.3, 3.9]). In those without COPD (n = 2139), bronchiectasis was associated with more cough, mucus hypersecretion, and wheezing, but not with deteriorating lung function.

CONCLUSION

Bronchiectasis was present in 5.4% of our lung cancer screening participants and was associated with more respiratory symptoms and, in those with COPD, with lower lung function and more emphysema.

CLINICAL RELEVANCE STATEMENT

In a lung cancer screening population, bronchiectasis has a prevalence of 5.4% with a mainly mild severity. This finding is of little clinical relevance unless mild COPD is also present. In those subjects, bronchiectasis was associated with a lower lung function, more respiratory symptoms, and more emphysema.

KEY POINTS

• Bronchiectasis was found in 5.4% of lung cancer screening participants, consisting of (ex-)smokers with and without mild COPD. • In those with mild COPD, bronchiectasis was associated with a lower lung function, more respiratory symptoms, and more emphysema. • Incidental findings of mild bronchiectasis are not very relevant in a lung cancer screening population, unless COPD is also present.

Understanding the Added Value of High-Resolution CT Beyond Chest X-ray in Determining Extent of Physiologic Impairment

BACKGROUND

Sarcoidosis staging primarily has relied on the Scadding chest radiographic system, although chest CT imaging is finding increased clinical use.

RESEARCH QUESTION

Whether standardized chest CT scan assessment provides additional understanding of lung function beyond Scadding stage and demographics is unknown and the focus of this study.

STUDY DESIGN AND METHODS

We used National Heart, Lung, and Blood Institute study Genomics Research in Alpha-1 Antitrypsin Deficiency and Sarcoidosis (GRADS) cases of sarcoidosis (n = 351) with Scadding stage and chest CT scans obtained in a standardized manner. One chest radiologist scored all CT scans with a visual scoring system, with a subset read by another chest radiologist. We compared demographic features, Scadding stage and CT scan findings, and the correlation between these measures. Associations between spirometry and diffusing capacity of the lungs for carbon monoxide (Dlco) results and CT scan findings and Scadding stage were determined using regression analysis (n = 318). Agreement between readers was evaluated using Cohen's κ value.

RESULTS

CT scan features were inconsistent with Scadding stage in approximately 40% of cases. Most CT scan features assessed on visual scoring were associated negatively with lung function. Associations persisted for FEV1 and Dlco when adjusting for Scadding stage, although some CT scan feature associations with FVC became insignificant. Scadding stage was associated primarily with FEV1, and inclusion of CT scan features reduced significance in association between Scadding stage and lung function. Multivariable regression modeling to identify radiologic measures explaining lung function included Scadding stage for FEV1 and FEV1 to FVC ratio (P < .05) and marginally for Dlco (P < .15). Combinations of CT scan measures accounted for Scadding stage for FVC. Correlations among Scadding stage and CT scan features were noted. Agreement between readers was poor to moderate for presence or absence of CT scan features and poor for degree and location of abnormality.

INTERPRETATION

In this study, CT scan features explained additional variability in lung function beyond Scadding stage, with some CT scan features obviating the associations between lung function and Scadding stage. Whether CT scan features, phenotypes, or endotypes could be useful for treating patients with sarcoidosis needs more study.

Analyzing key elements of breathing patterns, deriving remaining variables, and identifying cutoff values in individuals with chronic respiratory disease and healthy subjects

BACKGROUND

Pulmonary physiology encompasses intricate breathing patterns (BPs), characterized by breathing frequency (Bf), volumes, and flows. The complexities intensify in the presence of interstitial lung disease (ILD) and chronic obstructive pulmonary disease (COPD), especially during exercise. This study seeks to identify pivotal factors driving changes among these variables and establish cutoff values, comparing their efficacy in differentiating BPs to traditional methods, specifically a breathing reserve (BR) of 30% and a Bf of 50 bpm.

METHODS

Screening 267 subjects revealed 23 with ILD, 126 with COPD, 33 healthy individuals, and the exclusion of 85 subjects. Lung function tests and ramp-pattern cardiopulmonary exercise testing (CPET) were conducted, identifying crucial BP elements. Changes were compared between groups at peak exercise. The area under the receiver operating characteristic curve (AUC) analysis determined cutoff values.

RESULTS

Inspiratory time (TI) remained constant at peak exercise for all subjects (two-group comparisons, all p=NS). Given known differences in expiratory time (TE) and tidal volume (VT) among ILD, COPD, and healthy states, constant TI could infer patterns for Bf, total breathing cycle time (TTOT=60/Bf), I:E ratio, inspiratory duty cycle (IDC, TI/TTOT), rapid shallow breathing index (Bf/VT), tidal inspiratory and expiratory flows (VT/TI and VT/TE), and minute ventilation (V̇E=Bf×VT) across conditions. These inferences aligned with measurements, with potential type II errors causing inconsistencies. RSBI of 23 bpm/L and VT/TI of 104 L/min may differentiate ILD from control, while V̇E of 54 L/min, BR of 30%, and VT/TE of 108 may differentiate COPD from control. BR of 21%, TE of 0.99 s, and IDC of .45 may differentiate ILD from COPD. The algorithm outperformed traditional methods (AUC 0.84-0.91 versus 0.59-0.90).

CONCLUSION

The quasi-fixed TI, in conjunction with TE and VT, proves effective in inferring time-related variables of BPs. The findings have the potential to significantly enhance medical education in interpreting cardiopulmonary exercise testing. Moreover, the study introduces a novel algorithm for distinguishing BPs among individuals with ILD, COPD, and those who are healthy.

Acute and Late Pulmonary Effects After Radiation Therapy in Childhood Cancer Survivors: A PENTEC Comprehensive Review

OBJECTIVES

The Pediatric Normal Tissue Effects in the Clinic (PENTEC) pulmonary task force reviewed dosimetric and clinical factors associated with radiation therapy (RT)-associated pulmonary toxicity in children.

METHODS

Comprehensive search of PubMed (1965-2020) was conducted to assess available evidence and predictive models of RT-induced lung injury in pediatric cancer patients (<21 years old). Lung dose for radiation pneumonitis (RP) was obtained from dose-volume histogram (DVH) data. RP grade was obtained from standard criteria. Clinical pulmonary outcomes were evaluated using pulmonary function tests (PFTs), clinical assessment, and questionnaires.

RESULTS

More than 2,400 abstracts were identified; 460 articles had detailed treatment and toxicity data; and 11 articles with both detailed DVH and toxicity data were formally reviewed. Pooled cohorts treated during 1999 to 2016 included 277 and 507 patients age 0.04 to 22.7 years who were evaluable for acute and late RP analysis, respectively. After partial lung RT, there were 0.4% acute and 2.8% late grade 2, 0.4% acute and 0.8% late grade 3, and no grade 4 to 5 RP. RP risk after partial thoracic RT with mean lung dose (MLD) <14 Gy and total lung V20Gy <30% is low. Clinical and self-reported pulmonary outcomes data included 8,628 patients treated during 1970 to 2013, age 0 to 21.9 years. At a median 2.9- to 21.9-year follow-up, patients were often asymptomatic; abnormal PFTs were common and severity correlated with lung dose. At ≥10-year follow-up, multi-institutional studies suggested associations between total or ipsilateral lung doses >10 Gy and pulmonary complications and deaths. After whole lung irradiation (WLI), pulmonary toxicity is higher; no dose response relationship was identified. Bleomycin and other chemotherapeutics at current dose regimens do not contribute substantially to adverse pulmonary outcomes after partial lung irradiation but increase risk with WLI.

CONCLUSIONS

After partial lung RT, acute pulmonary toxicity is uncommon; grade 2 to 3 RP incidences are <1%. Late toxicities, including subclinical/asymptomatic impaired pulmonary function, are more common (<4%). Incidence and severity appear to increase over time. Upon review of available literature, there appears to be low risk of pulmonary complications in children with MLD < 14 Gy and V20Gy <30% using standard fractionated RT to partial lung volumes. A lack of robust data limit guidance on lung dose/volume constraints, highlighting the need for additional work to define factors associated with RT-induced lung injury.

Utilizing data from the clinical pulmonary function laboratory to teach about respiratory physiology: illustrating airway-parenchymal interdependence

Here we demonstrate how data from the clinical pulmonary function lab can help students learn about the principle of airway-parenchymal interdependence. We examined the relationship between airway conductance (Gaw) and lung volume (thoracic gas volume, TGV) in 48 patients: 17 healthy; 20 with emphysema, expected to have reduced airway-parenchymal interdependence; and 11 with pulmonary fibrosis, expected to have increased airway-parenchymal interdependence. Our findings support these expectations, with the slope of Gaw vs. TGV being steeper among those with pulmonary fibrosis and flatter among those with emphysema, compared to the slope of the healthy group. This type of analytic approach, using real-world patient data readily available from any pulmonary function laboratory, can be used to explore other fundamental principles of respiratory physiology.NEW & NOTEWORTHY This report demonstrates how common data obtained from the clinical pulmonary function testing laboratory can be used to illustrate important principles of respiratory physiology. Here we show how the relationship between airway conductance and lung volume across different disease states reflects intrinsic differences in airway-parenchymal interdependence.

Lung Clearance Index as a Screening Parameter of Pulmonary Impairment in Patients under Immune Checkpoint Therapy: A Pilot Study

Background: Immune checkpoint blockade (ICB) has presented a breakthrough in the treatment of malignant tumors and increased the overall survival of patients with various tumor entities. ICB may also cause immune-related adverse events, such as pneumonitis or interstitial lung disease. The lung clearance index (LCI) is a multiple-breath washout technique offering information on lung pathology in addition to conventional spirometry. It measures the degree of pulmonary ventilation inhomogeneity and allows early detection of pulmonary damage, especially that to peripheral airways. Methods: This cross-sectional study compared the lung function of patients with melanoma or metastatic cutaneous squamous cell carcinoma who received programmed cell death 1 (PD-1) and cytotoxic T-Lymphocyte-associated Protein 4 (CTLA-4) antibodies, alone or in combination, to age- and sex-matched controls. Lung function was assessed using spirometry, according to American Thoracic Society and European Respiratory Society standards, the LCI, and a diffusion capacity of carbon monoxide (DLCO) measurement. Results: Sixty-one screened patients and thirty-eight screened controls led to nineteen successfully included pairs. The LCI in the ICB-treated patients was 8.41 ± 1.15 (mean ± SD), which was 0.32 higher compared to 8.07 ± 1.17 in the control group, but the difference was not significant (p = 0.452). The patients receiving their ICB therapy for under five months showed a significantly lower LCI (7.98 ± 0.77) compared to the ICB patients undergoing therapy for over five months (9.63 ± 1.22) at the point of testing (p = 0.014). Spirometric analysis revealed that the forced expiratory volume between 25 and 75% of the forced vital capacity (FEF25-75%) in the ICB-treated patients was significantly reduced (p = 0.047) compared to the control group. DLCO (%predicted and adjusted for hemoglobin) was 94.4 ± 19.7 in the ICB patients and 93.4 ± 21.7 in the control group (p = 0.734). Conclusions: The patients undergoing ICB therapy showed slightly impaired lung function compared to the controls. Longer periods of ICB treatment led to deterioration of the LCI, which may be a sign of a subclinical inflammatory process. The LCI is feasible and may be easily integrated into the clinical daily routine and could contribute to early detection of pulmonary (auto-)inflammation.

Clinical features and 1-year outcomes of variable obstruction in participants with preserved spirometry: results from the ECOPD study in China

BACKGROUND

There are limited data on the clinical features and longitudinal prognosis of variable obstruction, particularly among never smokers and different variable obstruction types. Therefore, we aimed to evaluate the clinical characteristics of the participants with variable obstruction and determine the relationship between variable obstruction and the development of chronic obstructive pulmonary disease (COPD) and the decline of lung function in a community-dwelling study of Chinese, especially among never smokers and different variable obstruction subtypes.

METHODS

Participants with preserved spirometry (postbronchodilator forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC) ≥0.70) at baseline from the Early COPD cohort were included in our analysis. Participants with variable obstruction (prebronchodilator FEV1/FVC <0.70) were compared with those without variable obstruction (prebronchodilator FEV1/FVC ≥0.70). We performed subgroup analyses in never smokers, former and current smokers, and different variable obstruction types (postbronchodilator FVC

RESULTS

The final analysis included 1140 participants with preserved spirometry (169 in the variable obstruction group) at baseline. Participants with variable obstruction were older, had lower lung function and had greater severe emphysema and computed tomography-defined air trapping than participants without variable obstruction. Participants with variable obstruction had a significantly increased risk of incident spirometry-defined COPD (relative risk: 3.22, 95% confidence interval 2.23 to 4.64, p <0.001) than those without variable obstruction after adjustment for covariates. These findings remained consistent among both former and current smokers, never smokers, and different variable obstruction types. Additionally, participants with variable obstruction had a faster decline in postbronchodilator FEV1/FVC (2.3±0.5%/year vs 0.9±0.4%/year, mean difference: 1.4 (95% confidence interval 0.5 to 2.3), p=0.002) than participants without variable obstruction after adjustment for covariates.

CONCLUSIONS

The results of our study revealed that variable obstruction can identify individuals who are at risk for the development of COPD and accelerated postbronchodilator FEV1/FVC decline in preserved spirometry.

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Key Words

• COPD epidemiology
• Respiratory Function Test

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MESH Headings

• Humans
• Male
• Spirometry
• Female
• Pulmonary Disease, Chronic Obstructive/physiopathology
• Pulmonary Disease, Chronic Obstructive/epidemiology
• Pulmonary Disease, Chronic Obstructive/diagnosis
• Middle Aged
• China/epidemiology
• Aged
• Forced Expiratory Volume
• Vital Capacity
• Smoking/epidemiology
• Smoking/adverse effects
• Lung/physiopathology
• Prognosis

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Grants

• the Local Innovative and Research Teams Project of Guangdong Pearl River Talents Programme
• the National Key Research and Development Programme

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Affiliation(s)

Fan Wu State Key Laboratory of Respiratory Disease & National Clinical Research Center for Respiratory Disease & National Center for Respiratory Medicine & Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China Guangzhou National Laboratory, Guangzhou, Guangdong, China
Haiqing Li State Key Laboratory of Respiratory Disease & National Clinical Research Center for Respiratory Disease & National Center for Respiratory Medicine & Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China
Zhishan Deng State Key Laboratory of Respiratory Disease & National Clinical Research Center for Respiratory Disease & National Center for Respiratory Medicine & Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China
Huajing Yang State Key Laboratory of Respiratory Disease & National Clinical Research Center for Respiratory Disease & National Center for Respiratory Medicine & Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China Guangzhou National Laboratory, Guangzhou, Guangdong, China
Youlan Zheng State Key Laboratory of Respiratory Disease & National Clinical Research Center for Respiratory Disease & National Center for Respiratory Medicine & Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China Guangzhou National Laboratory, Guangzhou, Guangdong, China
Ningning Zhao State Key Laboratory of Respiratory Disease & National Clinical Research Center for Respiratory Disease & National Center for Respiratory Medicine & Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China
Cuiqiong Dai State Key Laboratory of Respiratory Disease & National Clinical Research Center for Respiratory Disease & National Center for Respiratory Medicine & Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China
Jieqi Peng State Key Laboratory of Respiratory Disease & National Clinical Research Center for Respiratory Disease & National Center for Respiratory Medicine & Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China Guangzhou National Laboratory, Guangzhou, Guangdong, China
Lifei Lu State Key Laboratory of Respiratory Disease & National Clinical Research Center for Respiratory Disease & National Center for Respiratory Medicine & Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China
Zihui Wang State Key Laboratory of Respiratory Disease & National Clinical Research Center for Respiratory Disease & National Center for Respiratory Medicine & Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China
Xiang Wen State Key Laboratory of Respiratory Disease & National Clinical Research Center for Respiratory Disease & National Center for Respiratory Medicine & Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China
Shan Xiao State Key Laboratory of Respiratory Disease & National Clinical Research Center for Respiratory Disease & National Center for Respiratory Medicine & Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China
Kunning Zhou State Key Laboratory of Respiratory Disease & National Clinical Research Center for Respiratory Disease & National Center for Respiratory Medicine & Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China
Xiaohui Wu State Key Laboratory of Respiratory Disease & National Clinical Research Center for Respiratory Disease & National Center for Respiratory Medicine & Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China
Gaoying Tang State Key Laboratory of Respiratory Disease & National Clinical Research Center for Respiratory Disease & National Center for Respiratory Medicine & Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China
Qi Wan State Key Laboratory of Respiratory Disease & National Clinical Research Center for Respiratory Disease & National Center for Respiratory Medicine & Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China
Ruiting Sun State Key Laboratory of Respiratory Disease & National Clinical Research Center for Respiratory Disease & National Center for Respiratory Medicine & Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China
Jiangyu Cui State Key Laboratory of Respiratory Disease & National Clinical Research Center for Respiratory Disease & National Center for Respiratory Medicine & Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China
Changli Yang Wengyuan County People's Hospital, Shaoguan, Guangdong, China
Shengtang Chen Wengyuan County People's Hospital, Shaoguan, Guangdong, China
Jianhui Huang Lianping County People's Hospital, Heyuan, Guangdong, China
Shuqing Yu Lianping County People's Hospital, Heyuan, Guangdong, China
Yumin Zhou State Key Laboratory of Respiratory Disease & National Clinical Research Center for Respiratory Disease & National Center for Respiratory Medicine & Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China Guangzhou National Laboratory, Guangzhou, Guangdong, China
Pixin Ran State Key Laboratory of Respiratory Disease & National Clinical Research Center for Respiratory Disease & National Center for Respiratory Medicine & Guangzhou Institute of Respiratory Health, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China Guangzhou National Laboratory, Guangzhou, Guangdong, China

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Reference ranges for ambulatory heart rate measurements in a middle-aged population

BACKGROUND

Elevated heart rate (HR) predicts cardiovascular disease and mortality, but there are no established normal limits for ambulatory HR. We used data from the Swedish CArdioPulmonary Imaging Study to determine reference ranges for ambulatory HR in a middle-aged population. We also studied clinical correlates of ambulatory HR.

METHODS

A 24-hour ECG was registered in 5809 atrial fibrillation-free individuals, aged 50-65 years. A healthy subset (n=3942) was used to establish reference values (excluding persons with beta-blockers, cardiovascular disease, hypertension, heart failure, anaemia, diabetes, sleep apnoea or chronic obstructive pulmonary disease).Minimum HR was defined as the lowest 1-minute HR. Reference ranges are reported as means±SDs and 2.5th-97.5th percentiles. Clinical correlates of ambulatory HR were analysed with multivariable linear regression.

RESULTS

The average mean and minimum HRs were 73±9 and 48±7 beats per minute (bpm) in men and 76±8 and 51±7 bpm in women; the reference range for mean ambulatory HR was 57-90 bpm in men and 61-92 bpm in women. Average daytime and night-time HRs are also reported. Clinical correlates, including age, sex, height, body mass index, physical activity, smoking, alcohol intake, diabetes, hypertension, haemoglobin level, use of beta-blockers, estimated glomerular filtration rate, per cent of predicted forced expiratory volume in 1 s and coronary artery calcium score, explained <15% of the interindividual differences in HR.

CONCLUSION

Ambulatory HR varies widely in healthy middle-aged individuals, a finding with relevance for the management of patients with a perception of tachycardia. Differences in ambulatory HR between individuals are largely independent of common clinical correlates.

Changes in vitamins and trace elements after initiation of highly effective CFTR modulator therapy in children and adults with cystic fibrosis - a real-life insight

BACKGROUND

Highly-effective CFTR-modulator therapy with elexa-/teza-/ivacaftor (ETI) has led to improvements in pulmonary outcomes, sweat chloride, body mass index (BMI) and quality of life in people with cystic fibrosis (CF). Improved uptake of fat-soluble vitamins and micronutrients has been reported for CFTR-modulators but data regarding ETI therapy is lacking.

METHODS

This single-center retrospective study evaluated forced expiratory volume in one second (FEV-1), sweat chloride, BMI, transaminases (AST, ALT), bilirubin, vitamins A, D, E, zinc and selenium in children and adults eligible for ETI. Parameters were assessed before and up to one year after initiation of ETI.

RESULTS

58 patients (median age m = 28 years, SD ± 11.6 years, 51.7% female14 < 18 years old) were included. FEV-1 and sweat chloride improved significantly after ETI. There were no changes in BMI or AST. ALT was increased significantly after 4 weeks of ETI but returned to normal levels in further course. Bilirubin levels remained elevated after ETI. Vitamin A was significantly higher 12 months after ETI. No changes were found for vitamins D, E, zinc and selenium.

CONCLUSIONS

This study adds to the evidence that improvements of some fat-soluble vitamin levels can be found after ETI. No changes regarding micronutrients were noted. Individualized follow-up and supplementation are recommended.

Evaluating the diagnostic and therapeutic significance of KL-6 in patients with interstitial lung diseases

Background

This study aimed to assess the diagnostic value of Krebs von den Lungen-6 (KL-6), Surfactant protein-A (SP-A), SP-D and molecular matrixmetalloproteinase-7 (MMP-7) in discriminating patients with interstitial lung diseases (ILDs) from disease control subjects.

Methods

Serum levels of KL-6, SP-A, SP-D and MMP-7 were measured in both the ILD and non-ILD (NILD) groups. Receiver operating characteristic (ROC) curve analysis was conducted to evaluate the diagnostic potential of these markers and laboratory indices. High-resolution computed tomography (HRCT) fibrosis scores were determined, and their correlation with the serum markers was analyzed.

Results

Serum levels of KL-6 and MMP-7 were significantly elevated in the ILD group compared to the control group, while no significant differences were observed for SP-A and SP-D. ROC analysis of KL-6 demonstrated superior diagnostic accuracy, with a sensitivity of 76.36%, specificity of 91.07%, and an area under curve (AUC) of 0.902 (95%CI 0.866-0.945). These findings were consistent across an additional cohort. Correlation analysis revealed a link between KL-6 levels at initial diagnosis and HRCT fibrosis scores, indicating disease severity. Moreover, a negative correlation was found between KL-6 and pulmonary function indices, reflecting disease progression. Patients with increased 12-month HRCT fibrosis score showed higher lactate dehydrogenase (LDH) levels, with LDH exhibiting an AUC of 0.767 (95% CI: 0.520-0.927) as a predictor of progression.

Conclusions

Serum KL-6 detection proves to be a valuable tool for accurately distinguishing ILDs from control subjects. While KL-6 shows a correlation with HRCT fibrosis scores and a negative association with pulmonary function indices, its predictive value for ILDs prognosis is limited.

Trial registration

This study received retrospective approval from the Ethical Committee of Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China (institutional review board ID: TJ-IRB20210331, date: 2021.03.30).

Effects of donor smoking history on early post-transplant lung function measured by oscillometry

Introduction

Prior studies assessing outcomes of lung transplants from cigarette-smoking donors found mixed results. Oscillometry, a non-invasive test of respiratory impedance, detects changes in lung function of smokers prior to diagnosis of COPD, and identifies spirometrically silent episodes of rejection post-transplant. We hypothesise that oscillometry could identify abnormalities in recipients of smoking donor lungs and discriminate from non-smoking donors.

Methods

This prospective single-center cohort study analysed 233 double-lung recipients. Oscillometry was performed alongside routine conventional pulmonary function tests (PFT) post-transplant. Multivariable regression models were constructed to compare oscillometry and conventional PFT parameters between recipients of lungs from smoking vs non-smoking donors.

Results

The analysis included 109 patients who received lungs from non-smokers and 124 from smokers. Multivariable analysis identified significant differences between recipients of smoking and non-smoking lungs in the oscillometric measurements R5-19, X5, AX, R5z and X5z, but no differences in %predicted FEV1, FEV1/FVC, %predicted TLC or %predicted DLCO. An analysis of the smoking group also demonstrated associations between increasing smoke exposure, quantified in pack years, and all the oscillometry parameters, but not the conventional PFT parameters.

Conclusion

An interaction was identified between donor-recipient sex match and the effect of smoking. The association between donor smoking and oscillometry outcomes was significant predominantly in the female donor/female recipient group.

The contribution of estimated dead space fraction to mortality prediction in patients with chronic obstructive pulmonary disease-a new proposal

Background

Mortality due to chronic obstructive pulmonary disease (COPD) is increasing. However, dead space fractions at rest (VD/VTrest) and peak exercise (VD/VTpeak) and variables affecting survival have not been evaluated. This study aimed to investigate these issues.

Methods

This retrospective observational cohort study was conducted from 2010-2020. Patients with COPD who smoked, met the Global Initiatives for Chronic Lung Diseases (GOLD) criteria, had available demographic, complete lung function test (CLFT), medication, acute exacerbation of COPD (AECOPD), Charlson Comorbidity Index, and survival data were enrolled. VD/VTrest and VD/VTpeak were estimated (estVD/VTrest and estVD/VTpeak). Univariate and multivariable Cox regression with stepwise variable selection were performed to estimate hazard ratios of all-cause mortality.

Results

Overall, 14,910 patients with COPD were obtained from the hospital database, and 456 were analyzed after excluding those without CLFT or meeting the lung function criteria during the follow-up period (median (IQR) 597 (331-934.5) days). Of the 456 subjects, 81% had GOLD stages 2 and 3, highly elevated dead space fractions, mild air-trapping and diffusion impairment. The hospitalized AECOPD rate was 0.60 ± 2.84/person/year. Forty-eight subjects (10.5%) died, including 30 with advanced cancer. The incidence density of death was 6.03 per 100 person-years. The crude risk factors for mortality were elevated estVD/VTrest, estVD/VTpeak, ≥2 hospitalizations for AECOPD, advanced age, body mass index (BMI) <18.5 kg/m2, and cancer (hazard ratios (95% C.I.) from 1.03 [1.00-1.06] to 5.45 [3.04-9.79]). The protective factors were high peak expiratory flow%, adjusted diffusing capacity%, alveolar volume%, and BMI 24-26.9 kg/m2. In stepwise Cox regression analysis, after adjusting for all selected factors except cancer, estVD/VTrest and BMI <18.5 kg/m2 were risk factors, whereas BMI 24-26.9 kg/m2 was protective. Cancer was the main cause of all-cause mortality in this study; however, estVD/VTrest and BMI were independent prognostic factors for COPD after excluding cancer.

Conclusions

The predictive formula for dead space fraction enables the estimation of VD/VTrest, and the mortality probability formula facilitates the estimation of COPD mortality. However, the clinical implications should be approached with caution until these formulas have been validated.

Unveiling the Knowledge Frontier: A Scientometric Analysis of COPD with Sarcopenia

Objective

Numerous articles and reviews addressing the intersection of Chronic Obstructive Pulmonary Disease (COPD) with sarcopenia have been documented. However, a significant gap exists in the literature concerning scientometric analysis in this field. This study aimed to concentrate on recent research and elucidate emerging research areas through the examination of COPD with sarcopenia.

Methods

Articles in the field were systematically retrieved from the Web of Science Core Collections (WoSCC) spanning from 2003 to 2022. The analysis employed scientometric and keyword analyses through specialized software, including VOSviewer, CiteSpace, and Origin.

Results

A comprehensive analysis of 758 articles and reviews in the field of COPD with sarcopenia revealed the United States as the leading contributor in terms of publications and overall influence. Maastricht University emerged as the most prolific institution, with Schols Annemie M. W. J. being identified as the most influential scholar in this field. The International Journal of Chronic Obstructive Pulmonary Disease emerged as the most prolific journal. Notably, COPD with sarcopenia exhibits frequent associations with other diseases, underscoring the complexity of the topic and emphasizing the necessity for comprehensive treatment. Mechanistic and diagnostic aspects, particularly computed tomography, are pivotal in this research field. Osteoporosis emerges as a prospective avenue for future research, encompassing both COPD and sarcopenia. Furthermore, nutrition and physical activity are integral components for managing COPD patients with sarcopenia.

Conclusion

This study delineates the distribution of fields, the knowledge structure, and the evolution of major research topics related to COPD with sarcopenia. The identification of keyword hotspots enhances the understanding of the occurrence, development, and future study trends associated with the topic.

Efficacy and safety of a music-therapy facilitated pulmonary telerehabilitation program in COPD patients: the COPDMELODY study protocol

Despite considerable evidence for the benefit in chronic obstructive pulmonary disease (COPD), the implementation of pulmonary rehabilitation (PR) is insufficient. However, music therapy may help address this gap due to its unique benefits. Therefore, we aimed to develop a music-therapy facilitated pulmonary telerehabilitation program based on rhythm-guided walking, singing, and objective telemonitoring. A supervised, parallel-group, single-blinded, randomized controlled clinical trial will be conducted, including 75 patients with COPD anticipated to be randomized in a 1:1:1 ratio into three groups. The intervention groups will receive a 12-week remotely monitored rehabilitation program, while the usual care group will not receive any rehabilitation interventions. Of the two intervention groups, the multi-module music therapy group will contain rhythm-guided walking and singing training, while the rhythm-guided walking group will only include music tempo-guided walking. The primary outcome is the distance of the incremental shuttle walking test. Secondary outcomes include respiratory muscle function, spirometry, lower extremity function, symptoms, quality of life, anxiety and depression levels, physical activity level, training adherence, and safety measurements. The results of this study can contribute to develop and evaluate a home-based music-facilitated rehabilitation program, which has the potential to act as a supplement and/or substitute (according to the needs) for traditional center-based PR in patients with stable COPD. Clinical trial registration: https://classic.clinicaltrials.gov/, NCT05832814.

Dose-response relationship between lung function and chest imaging response to silica exposures in artificial stone manufacturing workers

BACKGROUND

Occupational exposure to artificial stone, a popular material used for countertops, can cause accelerated silicosis, but the precise relationship between silica dose and disease development is unclear.

OBJECTIVES

This study evaluated the impact of silica exposure on lung function and chest imaging in artificial stone manufacturing workers.

METHODS

Questionnaire and spirometry assessments were administered to workers in two plants. A high-exposure subset underwent further evaluation, including chest CT and DLco. Weighting factors, assigned as proxies for silica exposure, were based on work tasks. Individual cumulative exposures were estimated using area concentration measurements and time spent in specific areas. Exposure-response associations were analyzed using linear and logistic regression models.

RESULTS

Among 65 participants, the mean cumulative silica exposure was 3.61 mg/m3-year (range 0.0001 to 44.4). Each 1 mg/m3-year increase was associated with a 0.46% reduction in FVC, a 0.45% reduction in FEV1, and increased lung function abnormality risk (aOR = 1.27, 95% CI = 1.03-1.56). Weighting factors correlated with cumulative exposures (Spearman correlation = 0.59, p < 0.0001), and weighted tenure was associated with lung function abnormalities (aOR = 1.04, 95% CI = 1.01-1.09). Of 37 high-exposure workers, 19 underwent chest CT, with 12 (63%) showing abnormal opacities. Combining respiratory symptoms, lung function, and chest X-ray achieved 91.7% sensitivity and 75% specificity for predicting chest CT abnormalities.

CONCLUSION

Lung function and chest CT abnormalities occur commonly in artificial stone workers. For high-exposure individuals, abnormalities on health screening could prompt further chest CT examination to facilitate early silicosis detection.

Clinical and functional characteristics, possible causes, and impact of chronic cough in patients with cerebellar ataxia, neuropathy, and bilateral vestibular areflexia syndrome (CANVAS)

Cerebellar ataxia with neuropathy and bilateral vestibular areflexia syndrome (CANVAS) is an hereditary autosomal recessive disease. Recent studies propose including chronic cough (CC) as a symptom of CANVAS. For 10 patients with CANVAS as genetically confirmed by biallelic expansion of the AAGG repeat motif (AAGGGexp) in intron 2 of replication factor C subunit 1 (RFC1), our aim was, as a multidisciplinary team, to describe clinical and functional characteristics and possible causes of CC following European Respiratory Society (ERS) recommendations, and to evaluate CC impact on quality of life (QoL) using self-administered questionnaires (Cough Severity Diary, Leicester Cough Questionnaire, Discrete Emotions Questionnaire, and EQ-5D-5L). In all 10 patients, the CC was a dry cough that developed several years prior to the neurological symptoms (mean 14.2 years); 7 patients had symptoms compatible with gastroesophageal reflux (GER), 5 with pathological GER diagnosed by 24-h esophageal pH testing, and 6 patients had impaired esophageal motility diagnosed by high-resolution esophageal manometry, most frequently ineffective peristalsis. Although further studies are required for confirmation, we conclude that CC may be a characteristic prodrome of CANVAS and may be related to GER and esophageal disorders. Furthermore, CC affects patients' QoL, especially in the psychosocial sphere.

Effect of respiratory muscle endurance training on performance and respiratory function in professional cyclists during the off-season

BACKGROUND

The study aimed to analyze the effect of respiratory muscle endurance training (RMT) on performance and respiratory function in professional road cyclists during the off-season period.

METHODS

Twenty professional road cyclists from the Czech Republic were divided into the control (CON) (N.=10) and the RMT (N.=10) groups. Cyclists from the RMT group accomplished 30 sessions over 10 weeks. Performance in the incremental cycling test and respiratory capacity via test were assessed before and after 10 weeks in both groups. The comparison between and within the groups was performed, together with effect size and delta % (P<0.05).

RESULTS

Significant effects on respiratory function during the exercise, on lung volume utilization at 90% of VO2max (TV-90%) and maximal voluntary ventilation (MVV) were found in RMT compared to the CON group, with a moderate effect size (0.71 and 0.61), and improvements of 13% and 14%, respectively. Parameters of performance in the cycling protocol and respiratory function at rest presented better values in the RMT group, however with no significance and in minor magnitude.

CONCLUSIONS

Using RMT during off-season benefits professional road cyclists by improving the major efficiency of respiratory function during progressive efforts. Therefore, the protocol of RMT could be used as an ergogenic aid during this period in order to maintain respiratory adaptations, optimizing the pre-season training. Adjustments can be made to improve the parameters outcomes.

Neural oscillations underlying the neural gating of respiratory sensations in generalized anxiety disorder

Individuals with generalized anxiety disorder (GAD) have been shown to have altered neural gating of respiratory sensations (NGRS) using respiratory-related evoked potentials (RREP); however, corresponding neural oscillatory activities remain unexplored. The present study aimed to investigate altered NGRS in individuals with GAD using both time and time-frequency analysis. Nineteen individuals with GAD and 28 healthy controls were recruited. Paired inspiratory occlusions were delivered to elicit cortical neural activations measured from electroencephalography. The GAD group showed smaller N1 amplitudes to the first stimulus (S1), lower evoked gamma and larger evoked beta oscillations compared to controls. Both groups showed larger N1, P3, beta power and theta power in response to S1 compared to S2, suggesting a neural gating phenomenon. These findings suggest that N1, gamma and beta frequency oscillations may be indicators for altered respiratory sensation in GAD populations and that the N1, P3, beta and theta oscillations can reflect the neural gating of respiratory sensations.

The relationship of fat and muscle measurements with emphysema and bronchial wall thickening in smokers

Introduction

Differences in body composition in patients with COPD may have important prognostic value and may provide opportunities for patient-specific management. We investigated the relation of thoracic fat and muscle with computed tomography (CT)-measured emphysema and bronchial wall thickening.

Methods

Low-dose baseline chest CT scans from 1031 male lung cancer screening participants from one site were quantified for emphysema, bronchial wall thickening, subcutaneous fat, visceral fat and skeletal muscle. Body composition measurements were performed by segmenting the first slice above the aortic arch using Hounsfield unit thresholds with region growing and manual corrections. COPD presence and severity were evaluated with pre-bronchodilator spirometry testing.

Results

Participants had a median age of 61.5 years (58.6-65.6, 25th-75th percentile) and median number of 38.0 pack-years (28.0-49.5); 549 (53.2%) were current smokers. Overall, 396 (38.4%) had COPD (256 Global Initiative for Chronic Obstructive Lung Disease (GOLD) 1, 140 GOLD 2-3). Participants with COPD had less subcutaneous fat, visceral fat and skeletal muscle (p<0.001 for all). With increasing GOLD stages, subcutaneous (p=0.005) and visceral fat values (p=0.004) were higher, and skeletal muscle was lower (p=0.004). With increasing severity of CT-derived emphysema, subcutaneous fat, visceral fat and skeletal muscle values were lower (p<0.001 for all). With increasing CT-derived bronchial wall thickness, subcutaneous and visceral fat values were higher (p<0.001 for both), without difference in skeletal muscle. All statistical relationships remained when adjusted for age, pack-years and smoking status.

Conclusion

COPD presence and emphysema severity are associated with smaller amounts of thoracic fat and muscle, whereas bronchial wall thickening is associated with fat accumulation.

High S100A9 level predicts poor survival, and the S100A9 inhibitor paquinimod is a candidate for treating idiopathic pulmonary fibrosis

BACKGROUND

S100A9 is a damage-associated molecular pattern protein that may play an important role in the inflammatory response and fibrotic processes. Paquinimod is an immunomodulatory compound that prevents S100A9 activity. Its safety and pharmacokinetics have been confirmed in human clinical trials. In this study, we investigated the effects of paquinimod in preventing the development of lung fibrosis in vivo and examined the prognostic values of circulatory and lung S100A9 levels in patients with idiopathic pulmonary fibrosis (IPF).

METHODS

The expression and localisation of S100A9 and the preventive effect of S100A9 inhibition on fibrosis development were investigated in a mouse model of bleomycin-induced pulmonary fibrosis. In this retrospective cohort study, the S100A9 levels in the serum and bronchoalveolar lavage fluid (BALF) samples from 76 and 55 patients with IPF, respectively, were examined for associations with patient survival.

RESULTS

S100A9 expression was increased in the mouse lungs, especially in the inflammatory cells and fibrotic interstitium, after bleomycin administration. Treatment with paquinimod ameliorated fibrotic pathological changes and significantly reduced hydroxyproline content in the lung tissues of mice with bleomycin-induced pulmonary fibrosis. Additionally, we found that paquinimod reduced the number of lymphocytes and neutrophils in BALF and suppressed endothelial-mesenchymal transition in vivo. Kaplan-Meier curve analysis and univariate and multivariate Cox hazard proportion analyses revealed that high levels of S100A9 in the serum and BALF were significantly associated with poor prognoses in patients with IPF (Kaplan-Meier curve analysis: p=0.037 (serum) and 0.019 (BALF); multivariate Cox hazard proportion analysis: HR=3.88, 95% CI=1.06 to 14.21, p=0.041 (serum); HR=2.73, 95% CI=1.05 to 7.10, p=0.039 (BALF)).

CONCLUSIONS

The present results indicate that increased S100A9 expression is associated with IPF progression and that the S100A9 inhibitor paquinimod is a potential treatment for IPF.

Inspiratory Muscle Dysfunction Mediates and Predicts a Disease Continuum of Hypercapnic Failure in Chronic Obstructive Pulmonary Disease

INTRODUCTION

Advanced chronic obstructive pulmonary disease (COPD) is associated with chronic hypercapnic failure. The present work aimed to comprehensively investigate inspiratory muscle function as a potential key determinant of hypercapnic respiratory failure in patients with COPD.

METHODS

Prospective patient recruitment encompassed 61 stable subjects with COPD across different stages of respiratory failure, ranging from normocapnia to isolated nighttime hypercapnia and daytime hypercapnia. Arterialized blood gas analyses and overnight transcutaneous capnometry were used for patient stratification. Assessment of respiratory muscle function encompassed body plethysmography, maximum inspiratory pressure (MIP), diaphragm ultrasound, and transdiaphragmatic pressure recordings following cervical magnetic stimulation of the phrenic nerves (twPdi) and a maximum sniff manoeuvre (Sniff Pdi).

RESULTS

Twenty patients showed no hypercapnia, 10 had isolated nocturnal hypercapnia, and 31 had daytime hypercapnia. Body plethysmography clearly distinguished patients with and without hypercapnia but did not discriminate patients with isolated nocturnal hypercapnia from those with daytime hypercapnia. In contrast to ultrasound parameters and transdiaphragmatic pressures, only MIP reflected the extent of hypercapnia across all three stages. MIP values below -48 cmH2O predicted nocturnal hypercapnia (area under the curve = 0.733, p = 0.052).

CONCLUSION

In COPD, inspiratory muscle dysfunction contributes to progressive hypercapnic failure. In contrast to invasive tests of diaphragm strength only MIP fully reflects the pathophysiological continuum of hypercapnic failure and predicts isolated nocturnal hypercapnia.

Development and evaluation of a computerized algorithm for the interpretation of pulmonary function tests

Pulmonary function tests (PFTs) are usually interpreted by clinicians using rule-based strategies and pattern recognition. The interpretation, however, has variabilities due to patient and interpreter errors. Most PFTs have recognizable patterns that can be categorized into specific physiological defects. In this study, we developed a computerized algorithm using the python package (pdfplumber) and validated against clinicians' interpretation. We downloaded PFT reports in the electronic medical record system that were in PDF format. We digitized the flow volume loop (FVL) and extracted numeric values from the reports. The algorithm used FEV1/FVC<0.7 for obstruction, TLC<80%pred for restriction and <80% or >120%pred for abnormal DLCO. The algorithm also used a small airway disease index (SADI) to quantify late expiratory flattening of the FVL to assess small airway dysfunction. We devised keywords for the python Natural Language Processing (NLP) package (spaCy) to identify obstruction, restriction, abnormal DLCO and small airway dysfunction in the reports. The algorithm was compared to clinicians' interpretation in 6,889 PFTs done between March 1st, 2018, and September 30th, 2020. The agreement rates (Cohen's kappa) for obstruction, restriction and abnormal DLCO were 94.4% (0.868), 99.0% (0.979) and 87.9% (0.750) respectively. In 4,711 PFTs with FEV1/FVC≥0.7, the algorithm identified 190 tests with SADI < lower limit of normal (LLN), suggesting small airway dysfunction. Of these, the clinicians (67.9%) also flagged 129 tests. When SADI was ≥ LLN, no clinician's reports indicated small airway dysfunction. Our results showed the computerized algorithm agreed with clinicians' interpretation in approximately 90% of the tests and provided a sensitive objective measure for assessing small airway dysfunction. The algorithm can improve efficiency and consistency and decrease human errors in PFT interpretation. The computerized algorithm works directly on PFT reports in PDF format and can be adapted to incorporate a different interpretation strategy and platform.

Pulmonary Function Tests Post-Stroke. Correlation between Lung Function, Severity of Stroke, and Improvement after Respiratory Muscle Training

Stroke is a significant cause of mortality and chronic morbidity caused by cardiovascular disease. Respiratory muscles can be affected in stroke survivors, leading to stroke complications, such as respiratory infections. Respiratory function can be assessed using pulmonary function tests (PFTs). Data regarding PFTs in stroke survivors are limited. We reviewed the correlation between PFTs and stroke severity or degree of disability. Furthermore, we reviewed the PFT change in stroke patients undergoing a respiratory muscle training program. We searched PubMed until September 2023 using inclusion and exclusion criteria in order to identify studies reporting PFTs post-stroke and their change after a respiratory muscle training program. Outcomes included lung function parameters (FEV1, FVC, PEF, MIP and MEP) were measured in acute or chronic stroke survivors. We identified 22 studies of stroke patients, who had undergone PFTs and 24 randomised controlled trials in stroke patients having PFTs after respiratory muscle training. The number of patients included was limited and studies were characterised by great heterogeneity regarding the studied population and the applied intervention. In general, PFTs were significantly reduced compared to healthy controls and predicted normal values and associated with stroke severity. Furthermore, we found that respiratory muscle training was associated with significant improvement in various PFT parameters and functional stroke parameters. PFTs are associated with stroke severity and are improved after respiratory muscle training.

Evaluation of atherosclerosis as a risk factor in COPD patients by measuring the carotid intima-media thickness

BACKGROUND

This study aimed to evaluate atherosclerosis as comorbidity by measuring the carotid (bulb and common carotid artery) Carotid intima-media thickness in COPD-diagnosed patients and to evaluate the relationship of atherosclerosis with the prevalence of COPD, hypoxemia and hypercapnia.

METHODS

This study was conducted out between January 2019-December 2019 consisting of a total of 140 participants (70 COPD-diagnosed patients-70 healthy individuals). The COPD-diagnosed patients have been planned according to the selection and diagnosis criteria as per the GOLD 2019 guide. It is planned to evaluate as per prospective matching case-control study of the carotid thickness, radial gas analysis, spirometric and demographic characteristics of COPD diagnosed patients and healthy individuals.

RESULTS

The average Carotid intima-media thickness in COPD patients was 0.8746±0.161 (p<0.05), and the thickness of the carotid bulb was 1.04±0.150 (p<0.05). In the control group, the average CCA intima-media thickness was 0.6650±0.139 (p<0.05), and the thickness of the carotid bulb was 0.8250±0.15(p<0.05) For the carotid thickness that has increased in COPD diagnosed patients a significant relationship is determined between hypoxemia (p<0.05) and hypercapnia(p<0.05). A significant relationship determined between CIMT and severity of COPD (p<0.05) The CIMT was high in COPD patients with hypoxemia and hypercapnia(p<0.05).

CONCLUSION

Significant difference was determined between the severity (grades) of COPD (mild, moderate, severe, very severe) in carotid thickness. Also, CIMT was found to be high in patients who is in the early phases of the prevalence of COPD. In COPD-diagnosed patients, it was determined that severity of COPD, hypoxemia, hypercapnia and age were determining factors of atherosclerosis.

Age-related changes in the neural gating of respiratory sensations in humans

Background

Neural gating of respiratory sensations (NGRS) characterises the brain's ability to filter out repetitive respiratory sensory stimuli. This mechanism plays a crucial role in the neural processing of respiratory stimuli. However, whether ageing affects NGRS in healthy adults is still unclear. Therefore, we aimed to measure the effect of age on NGRS as well as the corresponding S1 and S2 components of the respiratory-related evoked potentials (RREPs).

Methods

Three age groups of healthy adults participated in this study: a young group (YG; age 20-39 years), a middle-aged group (MG; age 40-59 years) and an old group (OG; age ≥60 years). NGRS was measured by the RREPs in the electroencephalogram in response to short-paired respiratory occlusion stimuli (S1 and S2). The S2/S1 ratio of the RREP N1 amplitude (the negative deflection of the RREP at ∼85-135 ms) was used to characterise NGRS.

Results

The results showed a significantly smaller N1 S2/S1 ratio in the YG than in the MG (p=0.01) and OG (p=0.03). Further analysis showed that the S1 N1 amplitude was larger for the YG compared with the MG (p=0.03) and OG (p=0.007). Moreover, age was significantly correlated with the N1 S2/S1 ratio (r=0.43), with higher age relating to higher N1 S2/S1 ratios.

Conclusions

The greater N1 S2/S1 ratios observed in older adults suggest that ageing has a negative impact on the NGRS. This might contribute to increased experiences of respiratory sensations such as dyspnoea in ageing adults.

Association between serum uric acid levels and lung function in the NHANES cohort (2007-2012): A cross-sectional analysis of a diverse American population

BACKGROUND

Hyperuricemia has been linked to various health conditions. However, the relationship between uric acid (UA) levels and lung function remains debated.

METHODS

In a cross-sectional study of 6750 participants aged 20-69 from NHANES, we assessed UA levels and lung function (FVC and FEV1). We conducted regression analyses while adjusting for potential confounders.

RESULTS

After accounting for factors like age, sex, BMI, smoking, and more, we found a negative association between UA FVC and FEV1. Specifically, for every 0.1 mg/dL increase in UA, FEV1 decreased by 15.265 mL, and FVC decreased by 24.46 mL. No association was observed with FEV1/FVC. Subgroup analyses revealed similar negative correlations among various groups, particularly in non-Hispanic Black females under 60.

CONCLUSION

Serum UA levels are inversely associated with FEV1 and FVC in the American population, with a notable impact on non-Hispanic Black females under 60.