ERS/ATS technical standard on interpretive strategies for routine lung function tests

Long-term outcomes of pulmonary embolism in children and adolescents

ABSTRACT

Knowledge regarding the long-term consequences of pulmonary embolism (PE) in children is limited. This cohort study describes the long-term outcomes of PE in children who were followed-up at a single-center institution using a local protocol that included clinical evaluation, chest imaging, echocardiography, pulmonary function tests, and cardiopulmonary exercise tests at follow-up, starting 3 to 6 months after acute PE. Children objectively diagnosed with PE at age 0 to 18 years, who had ≥6 months of follow-up were included. Study outcomes consisted of PE resolution, PE recurrence, death, and functional outcomes (dyspnea, impaired pulmonary or cardiac function, impaired aerobic capacity, and post-PE syndrome). The frequency of outcomes was compared between patients with/without underlying conditions. In total, 150 patients were included; median age at PE was 16 years (25th-75th percentile, 14-17 years); 61% had underlying conditions. PE did not resolve in 29%, recurrence happened in 9%, and death in 5%. One-third of patients had at least 1 documented abnormal functional finding at follow-up (ventilatory impairments, 31%; impaired aerobic capacity, 31%; dyspnea, 26%; and abnormal diffusing capacity of the lungs to carbon monoxide, 22%). Most abnormalities were transient. When alternative explanations for the impairments were considered, the frequency of post-PE syndrome was lower, ranging between 0.7% and 8.5%. Patients with underlying conditions had significantly higher recurrence, more pulmonary function and ventilatory impairments, and poorer exercise capacity. Exercise intolerance was, in turn, most frequently because of deconditioning than to respiratory or cardiac limitation, highlighting the importance of physical activity promotion in children with PE.

Diagnostic Potential of Oscillometry: A Population-based Approach

Rationale: Respiratory resistance (Rrs) and reactance (Xrs) as measured by oscillometry and their intrabreath changes have emerged as sensitive parameters for detecting early pathological impairments during tidal breathing. Objectives: This study evaluates the prevalence and association of abnormal oscillometry parameters with respiratory symptoms and respiratory diseases in a general adult population. Methods: A total of 7,560 subjects in the Austrian LEAD (Lung, hEart, sociAl, boDy) Study with oscillometry measurements (computed with the Resmon Pro FULL; Restech Srl) were included in this study. The presence of respiratory symptoms and doctor-diagnosed respiratory diseases was assessed using an interview-based questionnaire. Rrs and Xrs at 5 Hz, their inspiratory and expiratory components, the area above the Xrs curve, and the presence of tidal expiratory flow limitation were analyzed. Normality ranges for oscillometry parameters were defined. Measurements and Main Results: The overall prevalence of abnormal oscillometry parameters was 20%. The incidence of abnormal oscillometry increased in the presence of symptoms or diagnoses: 17% (16-18%) versus 27% (25-29%), P < 0.0001. All abnormal oscillometry parameters except Rrs at 5 Hz were significantly associated with respiratory symptoms/diseases. Significant associations were found, even in subjects with normal spirometry, with abnormal oscillometry incidence rates increasing by 6% (4-8%; P < 0.0001) in subjects with symptoms or diagnoses. Conclusions: Abnormal oscillometry parameters are present in one-fifth of this adult population and are significantly associated with respiratory symptoms and disease. Our findings underscore the potential of oscillometry as a tool for detecting and evaluating respiratory impairments, even in individuals with normal spirometry.

Alpha-1 Antitrypsin PI M Heterozygotes with Rare Variants: Do They Need a Clinical and Functional Follow-Up?

(1) Background: Few data are available on the risk of airway dysfunction in protease inhibitor (PI*) M heterozygotes carrying rare null or deficient allelic variants of the gene SERPINA-1 (PI*MR). (2) Methods: In this observational study, in a cohort of PI*MR heterozygotes, we evaluated respiratory functional parameters at baseline and at one-year follow-up. Moreover, we compared such parameters with those of the PI*MZ and PI*MS patients. (3) Results: A total of 60 patients were recruited; 35 PI*MR, 11 PI*MZ and 14 PI*MS. At the annual follow-up, the PI*MR and PI*MZ patients demonstrated a significantly higher FEV1 decline than the PI*MS group (p = 0.04 and p = 0.018, respectively). The PI*MR patients showed a significant increase in DLCO annual decline in comparison with the PI*MS group (p = 0.02). At baseline, the PI*MR smoking patients, compared with nonsmokers, showed statistically significant lower values of FEV1, FEV1/FVC and DLCO (p = 0.0004, p < 0.0001, p = 0.007, respectively) and, at the one-year follow-up, they displayed a significantly higher FEV1 and DLCO decline (p = 0.0022, p = 0.011, respectively). PI*MR heterozygotes with COPD showed a significantly higher FEV1, FEV1/FVC and DLCO annual decline in comparison with healthy PI*MR (p = 0.0083, p = 0.043, p = 0.041). (4) Conclusions: These results suggest that PI*MR heterozygotes, particularly smokers with COPD, have a greater annual decline in respiratory functional parameters and need to be monitored.

Characteristics and Determinants of Pulmonary Long COVID

RATIONALE

Persistent cough and dyspnea are prominent features of post-acute sequelae of SARS-CoV-2 (termed 'Long COVID'); however, physiologic measures and clinical features associated with these pulmonary symptoms remain poorly defined.

OBJECTIVES

Using longitudinal pulmonary function testing (PFTs) and CT imaging, this study aimed to identify the characteristics and determinants of pulmonary Long COVID.

METHODS

The University of Alabama at Birmingham Pulmonary Long COVID cohort was utilized to characterize lung defects in patients with persistent pulmonary symptoms after resolution primary COVID infection. Longitudinal PFTs including total lung capacity (TLC) and diffusion limitation of carbon monoxide (DLCO) were used to evaluate restriction and diffusion impairment over time in this cohort. Analysis of chest CT imaging was used to phenotype the pulmonary Long COVID pathology. Risk factors linked to development of pulmonary Long COVID were estimated using univariate and multivariate logistic regression models.

MEASUREMENTS AND MAIN RESULTS

Longitudinal evaluation 929 patients with post-COVID pulmonary symptoms revealed diffusion impairment (DLCO ≤80%) and restriction (TLC ≤80%) in 51% of the cohort (n=479). In multivariable logistic regression analysis (adjusted odds ratio; aOR, 95% confidence interval [CI]), invasive mechanical ventilation during primary infection conferred the greatest increased odds of developing pulmonary Long COVID with diffusion impaired restriction (aOR=10.9 [4.09-28.6]). Finally, a sub-analysis of CT imaging identified evidence of fibrosis in this population.

CONCLUSIONS

Persistent diffusion impaired restriction was identified as a key feature of pulmonary Long COVID. Subsequent clinical trials should leverage combined symptomatic and quantitative PFT measurements for more targeted enrollment of pulmonary Long COVID patients.

Lung function assessment in children with Long-Covid syndrome

INTRODUCTION

A significant percentage of patients who survived the Coronavirus Infection Disease 2019 (COVID-19) showed persistent general and respiratory symptoms even months after recovery. This condition, called Post-Acute Sequelae of COVID-19 or Long-Covid syndrome (LCS), has been described also in children with positive history for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Little is known about the pathophysiologic mechanisms underlying this syndrome. The aim of this study was to investigate any difference between children with LCS and asymptomatic peers with previous COVID-19 in terms of lung function and lung ultrasound (LUS) patterns. Secondly, we tested associations between lung function abnormalities and LUS findings with Long-Covid.

METHODS

We carried out a prospective, descriptive, observational study including 58 children aged 5-17 years: 28 with LCS compared to 30 asymptomatic children with previous COVID-19. We collected demographic data, history of asthma, allergy or smoke exposure, and acute COVID-19 symptoms. After a median period of 4.5 months (1%-95% range 2-21) since the infection, lung function was assessed by spirometry, body plethysmography, diffusion lung capacity for carbon monoxide (DLCO). Airways inflammation was investigated by fractional exhaled nitric oxide (FeNO). LUS was performed independently by two experienced clinicians.

RESULTS

We found that children with LCS were older than controls (mean (SD) 12 (4.1) vs. 9.7 (2.6); p = .04). Children with LCS complained more frequently fatigue (46.4%), cough (17.9%), exercise intolerance (14.3%) and dyspnea (14.3%). Lung function was normal and similar between the two groups. The frequency of LUS abnormalities was similar between the two groups (43.3% children with LCS vs. 56.7% controls; p = .436). Children with LCS showed lower FeNO values (log difference -0.30 (CI 95% -0.50, -0.10)), but no association of LCS with a lower lung function and abnormal LUS findings was found.

CONCLUSIONS

LCS seems to be more frequent in older age children. Lung functional and structural abnormalities were not different between children with LCS and asymptomatic subjects with previous COVID-19. In addition, children with LCS showed lower FeNO values than controls, suggesting its potential role as a marker in LCS. However, further and larger studies are needed to confirm our findings.

Biologics (mepolizumab and omalizumab) induced remission in severe asthma patients

BACKGROUND

Asthma remission has emerged as a potential treatment goal. This study evaluated the effectiveness of two biologics (mepolizumab/omalizumab) in achieving asthma remission.

METHODS

This observational study included 453 severe asthma patients (41% male; mean age ± SD 55.7 ± 14.7 years) from two real-world drug registries: the Australian Mepolizumab Registry and the Australian Xolair Registry. The composite outcome clinical remission was defined as zero exacerbations and zero oral corticosteroids during the previous 6 months assessed at 12 months and 5-item Asthma Control Questionnaire (ACQ-5) ≤1 at 12 months. We also assessed clinical remission plus optimization (post-bronchodilator FEV1 ≥80%) or stabilization (post-bronchodilator FEV1 not greater than 5% decline from baseline) of lung function at 12 months. Sensitivity analyses explored various cut-offs of ACQ-5/FEV1 scores. The predictors of clinical remission were identified.

RESULTS

29.3% (73/249) of AMR and 22.8% (37/162) of AXR cohort met the criteria for clinical remission. When lung function criteria were added, the remission rates were reduced to 25.2% and 19.1%, respectively. Sensitivity analyses identified that the remission rate ranged between 18.1% and 34.9% in the AMR cohort and 10.6% and 27.2% in the AXR cohort. Better lung function, lower body mass index, mild disease and absence of comorbidities such as obesity, depression and osteoporosis predicted the odds of achieving clinical remission.

CONCLUSION

Biologic treatment with mepolizumab or omalizumab for severe asthma-induced asthma remission in a subgroup of patients. Remission on treatment may be an achievable treatment target and future studies should consider remission as an outcome measure.

Forced Expiratory Volume in One Second Quotient (FEV1Q) as a Prognostic Factor in Amyotrophic Lateral Sclerosis Patients: Comparing Its Predictive Value to Other Lung Function Measurements

INTRODUCTION

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disorder affecting the first and second motor neurons. Forced vital capacity (FVC) and forced expiratory volume in one second (FEV1) have conventionally served as indicators of respiratory muscle strength. Recently, FEV1Q (FEV1 divided by the sex-specific first percentile values of absolute FEV1 in adults with lung disease) has been suggested as a predictor of mortality. While FVC has been utilized as a prognostic factor, FEV1Q has not yet been examined.

METHODS

This retrospective unicenter study evaluated FEV1Q as a predictor of mortality in ALS patients, comparing its predictive efficacy with other measurements, including FEV1, FVC, sniff nasal inspiratory pressure, and maximal inspiratory pressure. The study utilized univariate analysis for each variable employing the Cox proportional hazards model to determine the statistical significance and predictive power of each measurement.

RESULTS

Forty-five patients were included, female predominant (60%) and an average age at diagnosis of 69.2 ± 11 years. Almost all (95%) met the criteria for non-invasive ventilation (NIV) and initiated (93%) during the study period, a mean of 137 days after diagnosis. The mortality rate observed was 57%, occurring at a median of 398 days post-diagnosis. On average, patients underwent 1.7 pulmonary function tests, revealing a decline in various parameters, including FEV1, FEV1Q, and FVC. However, only FEV1Q was a statistically significant predictor of mortality (p < 0.0083) in a Cox regression analysis. A negative coefficient for FEV1Q indicated that higher values were associated with a reduced mortality risk, with an average FEV1Q of 2.68 observed at the time of death.

CONCLUSION

FEV1Q emerged as the only statistically significant predictor of mortality among the evaluated respiratory measurements in ALS patients. This study is the first to focus on applying FEV1Q in the clinical evaluation of ALS, marking an initial step in understanding its potential role in patient follow-up. However, further studies are needed before these findings can be incorporated into clinical practice.

Pulmonary Function and Survival 1 Year After Dupilumab Treatment of Acute Moderate to Severe Coronavirus Disease 2019: A Follow-up Study From a Phase 2a Trial

Background

We previously conducted a phase 2a randomized placebo-controlled trial of 40 subjects to assess the efficacy and safety of dupilumab use in people hospitalized with coronavirus disease 2019 (COVID-19) (NCT04920916). Based on our preclinical data suggesting that downstream pulmonary dysfunction with COVID-19 induced type 2 inflammation, we contacted patients from our phase 2a study at 1 year for assessment of post-COVID-19 conditions.

Methods

Subjects at 1 year after treatment underwent pulmonary function tests, high-resolution computed tomographic imaging, symptom questionnaires, neurocognitive assessments, and serum immune biomarker analysis, with subject survival also monitored. The primary outcome was the proportion of abnormal diffusion capacity for carbon monoxide (DLCO) or 6-minute walk test (6MWT) at the 1-year visit.

Results

Of those survivors who consented to 1-year visits (n = 16), subjects who had originally received dupilumab were less likely than those who received placebo to have an abnormal DLCO or 6MWT (Fisher exact P = .011; adjusted P = .058). As a secondary endpoint, we saw that 16% of subjects in the dupilumab group died by 1 year compared to 38% in the placebo group, though this was not statistically significant (log-rank P = .12). We did not find significant differences in neurocognitive testing, symptoms, or chest computed tomography between treatment groups but observed a larger reduction in eotaxin levels in those who received dupilumab.

Conclusions

In this observational study, subjects who received dupilumab during acute COVID-19 hospitalization were less likely to have a reduced DLCO or 6MWT, with a nonsignificant trend toward reduced mortality at 1 year compared to placebo.

Clinical features and outcomes of small airway disease in ANCA-associated vasculitis

BACKGROUND AND OBJECTIVE

To clarify the prevalence, features and outcomes of small airway disease (SAD) in a Chinese cohort with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) related pulmonary involvement.

METHODS

SAD was recorded when the manifestations of either centrilobular nodules or air trapping were observed according to CT scans, except for infection or other airway-related comorbidities. Baseline and follow-up data were collected retrospectively.

RESULTS

Of the 359 newly diagnosed AAV patients with pulmonary involvement, 92 (25.6%) had SAD, including 79 (85.9%) cases of anti-MPO-ANCA positive, 9 (9.8%) cases of anti-PR3-ANCA positive and 2 (2.2%) cases of double positive. Patients with SAD were more likely to be younger, female, non-smokers, have more ear-nose-throat (ENT) involvement, and have higher baseline Birmingham Vasculitis Activity Score (BVAS) compared to patients without SAD. Several AAV-related SAD patients have improved lung function and CT scans after immunosuppressive therapy. Patients with SAD had a better prognosis compared to those without SAD. When dividing all patients into three groups: isolated SAD (only small airway involvements), SAD with other lower airway involvements, and non-SAD, patients in the SAD with other lower airway involvements group had the highest risk of infection, while patients in the non-SAD group had the worst long-term outcomes. Similar results were observed in anti-MPO-ANCA positive patients when performing subgroup analyses.

CONCLUSION

SAD is a unique manifestation of AAV-related lung involvement and exhibits distinct clinical features. It is vital to focus on SAD because of its association with prognosis and infection in AAV patients, especially in anti-MPO-ANCA positive patients. Moreover, SAD might represent a better response to immunosuppressors.

Diffusing Capacity as a Predictor of Hospitalizations in a Clinical Cohort of Chronic Obstructive Pulmonary Disease

Rationale: Chronic obstructive pulmonary disease (COPD) hospitalizations are a major burden on patients. Diffusing capacity of the lung for carbon monoxide (DlCO) is a potential predictor that has not been studied in large cohorts. Objectives: This study used electronic health record data to evaluate whether clinically obtained DlCO predicts COPD hospitalizations. Methods: We performed time-to-event analyses of individuals with COPD and DlCO measurements from the Johns Hopkins COPD Precision Medicine Center of Excellence. Cox proportional hazard methods were used to model time from DlCO measurement to first COPD hospitalization and composite first hospitalization or death, adjusting for age, sex, race, body mass index, smoking status, forced expiratory volume in 1 second (FEV1), history of prior COPD hospitalization, and comorbidities. To identify the utility of including DlCO in risk models, area under the receiver operating curve (AUC) values were calculated for models with and without DlCO. Results were externally validated in a separate analogous cohort. Results: Of 2,793 participants, 368 (13%) had a COPD hospitalization within 3 years. In adjusted analyses, for every 10% decrease in DlCO% predicted, risk of COPD hospitalization increased by 10% (hazard ratio, 1.1; 95% confidence interval, 1.1-1.2; P < 0.001). Similar associations were observed for COPD hospitalizations or death. The model including demographics, comorbidities, FEV1, DlCO, and prior COPD hospitalizations performed well, with an AUC of 0.85 and an AUC of 0.84 in an external validation cohort. Conclusions: Diffusing capacity is a strong predictor of COPD hospitalizations in a clinical cohort of individuals with COPD, independent of airflow obstruction and prior hospitalizations. These findings support incorporation of DlCO in risk assessment of patients with COPD.

Precision Approaches to Chronic Obstructive Pulmonary Disease Management

Chronic obstructive pulmonary disease (COPD) is a leading cause of morbidity and mortality worldwide. COPD heterogeneity has hampered progress in developing pharmacotherapies that affect disease progression. This issue can be addressed by precision medicine approaches, which focus on understanding an individual's disease risk, and tailoring management based on pathobiology, environmental exposures, and psychosocial issues. There is an urgent need to identify COPD patients at high risk for poor outcomes and to understand at a mechanistic level why certain individuals are at high risk. Genetics, omics, and network analytic techniques have started to dissect COPD heterogeneity and identify patients with specific pathobiology. Drug repurposing approaches based on biomarkers of specific inflammatory processes (i.e., type 2 inflammation) are promising. As larger data sets, additional omics, and new analytical approaches become available, there will be enormous opportunities to identify high-risk individuals and treat COPD patients based on their specific pathophysiological derangements. These approaches show great promise for risk stratification, early intervention, drug repurposing, and developing novel therapeutic approaches for COPD.

Spirometric Interpretation and Clinical Relevance According to Different Reference Equations

BACKGROUND

Global Lung Function Initiative (GLI)-2012 reference equation is currently suggested for interpretation of spirometry results and a new local reference equation has been developed in South Korea. However, lung function profiles according to the different reference equations and their clinical relevance have not been identified in chronic obstructive pulmonary disease (COPD) patients.

METHODS

Our cross-sectional study evaluated Choi's, Korean National Health and National Examination Survey (KNHANES)-VI, and GLI-2012 reference equations. We estimated the percentages of predictive forced expiratory volume in one second (FEV1) and airflow limitation severity according to reference equations and analyzed their associations with patient reported outcomes (PROs): COPD assessment test (CAT) score, St. George's Respiratory Questionnaire for COPD patients (SGRQ-C) score, and six minute walk distance (6MWD).

RESULTS

In the eligible 2,180 COPD patients, lower predicted values of FEV1 and forced vital capacity (FVC) were found in GLI-2012 compared to Choi's and KNHANES-VI equations. GLI-2012 equation resulted in a lower proportion of patients being classified as FEV1 < 80% or FVC < 80% compared to the other equations. However, the Z-scores of FEV1 and FVC were similar between the KNHANES-VI and GLI-2012 equations. Three reference equations exhibited significant associations between FEV1 (%) and patient-reported outcomes (CAT score, SGRQ-C score, and 6MWD).

CONCLUSION

GLI-2012 reference equation may not accurately reflect FEV1 (%) in the Korean population, but the Z-score using GLI-2012 equation can be a viable option for assessing FEV1 and airflow limitation in COPD patients. Similar to the other two equations, the GLI-2012 equation demonstrated significant associations with PROs.

Respiratory sarcopenia screening in dialysis patients: cross-sectional and multicentre study protocol

BACKGROUND

Respiratory sarcopenia is characterized by the weakness of respiratory muscles associated with sarcopenia due to aging or systemic diseases such as chronic kidney disease (CKD). Patients with CKD undergoing dialysis are particularly susceptible to respiratory muscle weakness caused by factors such as fluid overload and electrolyte imbalance. This weakness not only affects ventilation but also impairs oxygen uptake and delivery to muscle tissue, potentially leading to severe sarcopenia. Thus, the objective of this study is to conduct a respiratory sarcopenia screening in patients with CKD undergoing haemodialysis (HD) and peritoneal dialysis (PD).

METHODS

This is an observational, cross-sectional and multicentre study conducted between March 2023 and March 2025. The study was approved by the Research Ethics Committee at two centres. Sarcopenia diagnosis is determined based on low handgrip strength and amount of appendicular skeletal muscle mass, assessed through bioelectrical impedance analysis. Respiratory sarcopenia is diagnosed in patients with sarcopenia who have low inspiratory muscle strength, evaluated through a manovacuometry test. The severity of sarcopenia and respiratory sarcopenia is defined, respectively, by low physical performance (measured using the Short Physical Performance Battery and Timed-Up and Go test) and pulmonary performance (measured through spirometry). Thus, this study will include 81 patients undergoing dialysis (41 on HD and 40 on PD) from three participating centres.

DISCUSSION

The literature has been focused on respiratory function in CKD; however, the relationship with sarcopenia remains understudied. We believe that, similar to appendicular skeleton muscles, the axial skeleton muscles are also likely to weaken with the presence of chronic disease, such as CKD.

A comparative study of bronchodilator response: utilizing pre-bronchodilator versus predicted normal values

BACKGROUND

A positive bronchodilator response has been defined as a 12% increase in the forced expiratory volume in one second (FEV1) or forced vital capacity (FVC) from their respective pre-bronchodilator values, combined with at least a 0.2 L absolute change. Recent recommendations suggested the use of the percent change in FEV1 and FVC relative to their predicted normal values without having applied them in patients with airflow obstruction. The aim of the current study was to compare the two approaches over a wide range of pre-bronchodilator FEV1 and FVC values.

METHODS

A retrospective review of consecutive patients undergoing spirometry and bronchodilator testing was completed. The change in FEV1 and FVC with a bronchodilator was expressed relative to the pre-bronchodilator and predicted normal FEV1 and FVC.

RESULTS

In 1,040 patients with a non-paradoxical change in FEV1, 19.0% had a ≥ 12% change in FEV1 using their pre-bronchodilator value compared to 5.7% using their predicted normal value. For FVC, the respective values were 12.7% vs. 5.8%. The difference was retained in patients with a ≥ 0.2 L change in FEV1 or FVC. In unobstructed patients, the upper threshold (two standard deviations above the mean) of the bronchodilator response was 14% for FEV1 and 10% for FVC using predicted normal values.

CONCLUSIONS

Expressing the percent change in FEV1 and FVC relative to predicted normal values reduces the over-estimation of the bronchodilator response, especially in patients with a very low pre-bronchodilator FEV1, including in those with a ≥ 0.2 L change in FEV1. Irrespective of pre-bronchodilator values, a ≥ 14% change in FEV1 and ≥ 10% change in FVC relative to the predicted normal values could be considered a positive bronchodilator response.

Functional Progression after Dose Suspension or Discontinuation of Nintedanib in Idiopathic Pulmonary Fibrosis: A Real-Life Multicentre Study

BACKGROUND

Idiopathic pulmonary fibrosis (IPF) is a chronic interstitial lung disease with rapidly progressive evolution and an unfavorable outcome. Nintedanib (NTD) is an antifibrotic drug that has been shown to be effective in slowing down the progression of the disease. The aim of our study was to examine the efficacy, especially in terms of the functional decline, and the safety profile of NTD in patients treated with the recommended dose and subjects who reduced or suspended the therapy due to the occurrence of adverse reactions.

METHODS

We conducted a real-life retrospective study based on the experience of NTD use in two centers between 2015 and 2022. Clinical data were evaluated at baseline, at 6 and 12 months after the NTD introduction in the whole population and in subgroups of patients who continued the full-dose treatment, at a reduced dosage, and at the discontinuation of treatment. The following data were recorded: the demographic features, IPF clinical features, NTD therapeutic dosage, tolerability and adverse events, pulmonary function tests (PFTs), the duration of treatment upon discontinuation, and the causes of interruption.

RESULTS

There were 54 IPF patients who were included (29.6% females, with a median (IQR) age at baseline of 75 (69.0-79.0) years). Twelve months after the introduction of the NTD therapy, 20 (37%) patients were still taking the full dose, 11 (20.4%) had reduced it to 200 mg daily, and 15 (27.8%) had stopped treatment. Gastrointestinal intolerance predominantly led to the dose reduction (13.0%) and treatment cessation (20.4%). There were two deaths within the initial 6 months (3.7%) and seven (13.0%) within 12 months. Compared to the baseline, the results of the PFTs remained stable at 6 and 12 months for the entire NTD-treated population, except for a significant decline in the DLCO (% predicted value) at both 6 (38.0 ± 17.8 vs. 43.0 ± 26.0; p = 0.041) and 12 months (41.5 ± 15.3 vs. 44.0 ± 26.8; p = 0.048). The patients who continued treatment at the full dose or a reduced dosage showed no significant differences in the FVC and the DLCO at 12 months. Conversely, those discontinuing the NTD exhibited a statistically significant decline in the FVC (% predicted value) at 12 months compared to the baseline (55.0 ± 13.5 vs. 70.0 ± 23.0; p = 0.035).

CONCLUSIONS

This study highlights the functional decline of the FVC at 12 months after the NTD initiation among patients discontinuing therapy but not among those reducing their dosage.

Within-breath oscillometry for identifying exercise-induced bronchoconstriction in pediatric patients reporting symptoms with exercise

Background

Evaluating oscillometry parameters separately for the inspiratory and expiratory breath phases and their within-breath differences can help to identify exercise-induced bronchoconstriction (EIB) in pediatric outpatients disclosing exercise-induced symptoms (EIS).

Aims

To assess the response in impedance parameters following an exercise challenge in patients reporting EIS.

Methods

Sixty-eight patients reporting EIS (34 asthmatics and 34 suspected of asthma, age mean = 10.8 years, range = 6.0-16.0) underwent an incremental treadmill exercise test. Spirometry was performed at baseline and 1, 5-, 10-, 15-, and 20-min post exercise. Oscillometry was performed at baseline and at 3- and 18-min post exercise. Bronchodilator response to 200 µg albuterol was then assessed. EIB was defined as a forced expiratory volume in 1 s (FEV1) fall ≥10% from baseline. Expiratory and inspiratory resistance (Rrs) and reactance (Xrs), their z-score (Ducharme et al. 2022), and their mean within-breath differences (ΔRrs = Rrsexp-Rrsinsp, ΔXrs = Xrsexp-Xrsinsp) were calculated. Receiver operating characteristic (ROC) curves and their areas (AUCs) were used to evaluate impedance parameters' performances in classifying EIB.

Results

Asthmatic patients developed EIB more frequently than those suspected of asthma [18/34 (52.9%) vs. 2/34 (5.9%), p < 0.001]. In the 20 subjects with EIB, Rrsinsp, Rrsexp, Xrsinsp, and Xrsexp peaked early (3'), and remained steady except for Xrsinsp, which recovered faster afterward. ΔXrs widened 18 min following the exercise and reversed sharply after bronchodilation (BD) (-1.81 ± 1.60 vs. -0.52 ± 0.80 cmH2O × s/L, p < 0.001). Cutoffs for EIB leading to the highest AUCs were a rise of 0.41 in z-score Rrsinsp (Se: 90.0%, Sp: 66.7%), and a fall of -0.64 in z-score Xrsinsp (Se: 90.0%, Sp: 75.0%). Accepting as having "positive" postexercise oscillometry changes those subjects who had both z-scores beyond respective cutoffs, sensitivity for EIB was 90.0% (18/20) and specificity, 83.3% (40/48).

Conclusion

Oscillometry parameters and their within-breath differences changed markedly in pediatric patients presenting EIB and were restored after the bronchodilator. Strong agreement between z-scores of inspiratory oscillometry parameters and spirometry supports their clinical utility, though larger studies are required to validate these findings in a broader population.

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 the effectiveness of Tadalafil on improving pulmonary function and asthma severity in severe asthmatic patients: a randomized controlled trial study

Phosphodiesterase inhibitors elevate the levels of cyclic adenosine monophosphate and cyclic guanosine monophosphate, which have been associated with various anti-inflammatory effects that can help alleviate asthma symptoms. This study aims to assess the impact of Tadalafil, a selective phosphodiesterase inhibitor, on pulmonary function in patients with asthma. This study was a randomized, double-blind clinical trial conducted in 2021 at Imam Khomeini Hospital in Ahvaz, Iran. The study enrolled 44 patients with severe asthma, who were divided equally into a Tadalafil group and a placebo group. The Tadalafil group received 20 mg/day of Tadalafil, while the placebo group received a placebo at the same dose. The patients' spirometry tests, asthma quality of life questionnaire, 6-minute walk distance, and quality of life were measured at the beginning of the study and one month later. The study results indicated that there was no statistically significant difference between the Tadalafil group and the placebo group in terms of pulmonary parameters (p>0.05). Furthermore, the scores for patients' quality of life (p=0.167) and the 6-minute walk test (p=0.148) at the end of the study did not show any statistically significant improvement compared to the placebo group. Results showed that the use of Tadalafil (20 mg) once daily for one month in patients with severe asthma did not affect clinical and laboratory outcomes.

Lung Involvement in Patients with Ulcerative Colitis: Relationship between Exhaled Nitric Oxide and Lung Function

Ulcerative colitis (UC) is characterized by immune system dysregulation with frequent extraintestinal manifestations, including airway involvement. A reduction in CO diffusing capacity and functional alterations in small airways have been described. An extended analysis of fractional exhaled nitric oxide (FeNO) may distinguish the sites of production, and the presence of small airway inflammation may be a useful, non-invasive marker for patient follow-up. The aim of our study was to compare the PFTs as well as FeNO and CANO values of UC patients with different clinical disease activities and healthy subjects to reveal lung function abnormalities and the presence of subclinical airway inflammation. We enrolled 42 adult outpatients at different clinical activity stages of UC (39 ± 13 years) and a healthy control group of 41 subjects (29 ± 3 years). C-reactive protein (CRP) and FeNO values at different flows (50,100, and 200 mL/s) were collected. All patients performed pulmonary function tests (PFTs) with static volumes and diffusing capacity (DLCO). FeNO and CANO values were significantly increased in UC patients when compared with controls (p = 0.0008 and p < 0.0001, respectively) and were proportional to disease activity (FeNO class 3: 28.1 ppb vs. classes 1-2: 7.7 ppb; CANO values class 3: 8.6 ppb vs. classes 1-2: 2.7 ppb (p < 0.0001)). TLC and DLCO were significantly reduced in severe (Mayo 3) UC patients (p = 0.010 and p = 0.003, respectively). The results of this study show significant lung functional abnormalities in UC patients and suggest the presence of airway inflammation directly correlated with disease activity, suggesting the need for an integrated approach in routine assessment.

Exercise-Induced Asthma: Managing Respiratory Issues in Athletes

Asthma is a complex respiratory condition characterized by chronic airway inflammation and variable expiratory airflow limitation, affecting millions globally. Among athletes, particularly those competing at elite levels, the prevalence of respiratory conditions is notably heightened, varying between 20% and 70% across specific sports. Exercise-induced bronchoconstriction (EIB) is a common issue among athletes, impacting their performance and well-being. The prevalence rates vary based on the sport, training environment, and genetics. Exercise is a known trigger for asthma, but paradoxically, it can also improve pulmonary function and alleviate EIB severity. However, athletes' asthma phenotypes differ, leading to varied responses to medications and challenges in management. The unique aspects in athletes include heightened airway sensitivity, allergen, pollutant exposure, and temperature variations. This review addresses EIB in athletes, focusing on pathogenesis, diagnosis, and treatment. The pathogenesis of EIB involves complex interactions between physiological and environmental factors. Airway dehydration and cooling are key mechanisms, leading to osmotic and thermal theories. Airway inflammation and hyper-responsiveness are common factors. Elite athletes often exhibit distinct inflammatory responses and heightened airway sensitivity, influenced by sport type, training, and environment. Swimming and certain sports pose higher EIB risks, with chlorine exposure in pools being a notable factor. Immune responses, lung function changes, and individual variations contribute to EIB in athletes. Diagnosing EIB in athletes requires objective testing, as baseline lung function tests can yield normal results. Both EIB with asthma (EIBA) and without asthma (EIBwA) must be considered. Exercise and indirect bronchoprovocation tests provide reliable diagnoses. In athletes, exercise tests offer effectiveness in diagnosing EIB. Spirometry and bronchodilation tests are standard approaches, but the diagnostic emphasis is shifting toward provocation tests. Despite its challenges, achieving an optimal diagnosis of EIA constitutes the cornerstone for effective management, leading to improved performance, reduced risk of complications, and enhanced quality of life. The management of EIB in athletes aligns with the general principles for symptom control, prevention, and reducing complications. Non-pharmacological approaches, including trigger avoidance and warming up, are essential. Inhaled corticosteroids (ICS) are the cornerstone of asthma therapy in athletes. Short-acting beta agonists (SABA) are discouraged as sole treatments. Leukotriene receptor antagonists (LTRA) and mast cell stabilizing agents (MCSA) are potential options. Optimal management improves the athletes' quality of life and allows them to pursue competitive sports effectively.

Relationships between symptoms and lung function in asthma and/or chronic obstructive pulmonary disease in a real-life setting: the NOVEL observational longiTudinal studY

BACKGROUND

The relationships between spirometric assessment of lung function and symptoms (including exacerbations) in patients with asthma and/or chronic obstructive pulmonary disease (COPD) in a real-life setting are uncertain.

OBJECTIVES

To assess the relationships between baseline post-bronchodilator (post-BD) spirometry measures of lung function and symptoms and exacerbations in patients with a physician-assigned diagnosis of asthma and/or COPD.

DESIGN

The NOVEL observational longiTudinal studY (NOVELTY) is a global, prospective, 3-year observational study.

METHODS

Logistic regression analysis was used to evaluate relationships. Spirometry measures were assessed as percent predicted (%pred). Symptoms were assessed at baseline, and exacerbations were assessed at baseline and Year 1.

RESULTS

A total of 11,181 patients in NOVELTY had spirometry data (asthma, n = 5903; COPD, n = 3881; asthma + COPD, n = 1397). A 10% lower post-BD %pred forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) - adjusted for age and sex - were significantly associated with dyspnea (modified Medical Research Council ⩾ grade 2), frequent breathlessness [St George's Respiratory Questionnaire (SGRQ)], frequent wheeze attacks (SGRQ), nocturnal awakening (Respiratory Symptoms Questionnaire; ⩾1 night/week), and frequent productive cough (SGRQ). Lower post-BD %pred FEV1 and, to a lesser extent, lower post-BD %pred FVC were significantly associated with ⩾1 physician-reported exacerbation at baseline or Year 1. This association was stronger in patients with COPD than in those with asthma.

CONCLUSION

In a real-life setting, reduced lung function is consistently associated with symptoms in patients with asthma, COPD, or asthma + COPD. The relationship with exacerbations is stronger in COPD only than in asthma.

TRAIL REGISTRATION

clinicaltrials.gov identifier: NCT02760329 (www.clinicaltrials.gov).

The alveolar fibroproliferative response in moderate to severe COVID-19-related acute respiratory distress syndrome and 1-yr follow-up

COVID-19-related acute respiratory distress syndrome (ARDS) can lead to long-term pulmonary fibrotic lesions. Alveolar fibroproliferative response (FPR) is a key factor in the development of pulmonary fibrosis. N-terminal peptide of procollagen III (NT-PCP-III) is a validated biomarker for activated FPR in ARDS. This study aimed to assess the association between dynamic changes in alveolar FPR and long-term outcomes, as well as mortality in COVID-19 ARDS patients. We conducted a prospective cohort study of 154 COVID-19 ARDS patients. We collected bronchoalveolar lavage (BAL) and blood samples for measurement of 17 pulmonary fibrosis biomarkers, including NT-PCP-III. We assessed pulmonary function and chest computed tomography (CT) at 3 and 12 mo after hospital discharge. We performed joint modeling to assess the association between longitudinal changes in biomarker levels and mortality at day 90 after starting mechanical ventilation. 154 patients with 284 BAL samples were analyzed. Of all patients, 40% survived to day 90, of whom 54 completed the follow-up procedure. A longitudinal increase in NT-PCP-III was associated with increased mortality (HR 2.89, 95% CI: 2.55-3.28; P < 0.001). Forced vital capacity and diffusion for carbon monoxide were impaired at 3 mo but improved significantly at one year after hospital discharge (P = 0.03 and P = 0.004, respectively). There was no strong evidence linking alveolar FPR during hospitalization and signs of pulmonary fibrosis in pulmonary function or chest CT images during 1-yr follow-up. In COVID-19 ARDS patients, alveolar FPR during hospitalization was associated with higher mortality but not with the presence of long-term fibrotic lung sequelae within survivors.NEW & NOTEWORTHY This is the first prospective study on the longitudinal alveolar fibroproliferative response in COVID-19 ARDS and its relationship with mortality and long-term follow-up. We used the largest cohort of COVID-19 ARDS patients who had consecutive bronchoalveolar lavages and measured 17 pulmonary fibroproliferative biomarkers. We found that a higher fibroproliferative response during admission was associated with increased mortality, but not correlated with long-term fibrotic lung sequelae in survivors.

The initial angle of the maximum expiratory flow-volume curve: a novel start-of-test criteria of spirometry in children

The aim of the present study was to define an initial angle called β and to assess its diagnostic value for identifying poor-quality maneuvers in spirometry testing in children. Furthermore, its predictive equation or normal value was explored. Children aged 4-14 years with respiratory symptoms who underwent spirometry were enrolled. Based on the efforts labeled during maneuvering and the quality control criteria of the guidelines, children were categorized into good-quality and poor-quality groups. According to ventilatory impairment, children in the good-quality group were divided into three subgroups: normal, restricted, and obstructed. Angle β was the angle between the line from the expiratory apex to the origin of coordinates and the x-axis of the maximal expiratory flow-volume (MEFV) curve. Demographic characteristics, angle β, and other spirometric parameters were compared among groups. The diagnostic values of angle β, forced expiratory time (FET), and their combination were assessed using receiver operating characteristic curves. Data from 258 children in the good-quality group and 702 healthy children in our previous study were used to further explore the predictive equation or normal value of angle β. The poor-quality group exhibited a significantly smaller angle β (76.44° vs. 79.36°; P < 0.001), significantly lower peak expiratory flow (PEF), FET, and effective FET (ETe), and significantly higher expiratory volume at peak flow rate (FEV-PEF) and ratio of extrapolated volume and forced vital capacity (EV/FVC) than the good-quality group. There was no significant difference in angle β among the normal, restricted, and obstructed groups. Logistic regression analysis revealed that smaller angle β and FET values indicated poor-quality MEFV curves. The combination of angle β < 74.58° and FET < 4.91 s had a significantly larger area under the curve than either one alone. The normal value of angle β of children aged 4-14 years was 78.40 ± 0.12°.   Conclusions: Angle β contributes to the quality control evaluation of spirometry in children. Both angle β < 74.58° and FET < 4.91 s are predictors of poor-quality MEFV curves, while their combination offers the highest diagnostic value. What is Known: • A slow start is one of the leading causes of poor-quality maximal expiratory flow-volume (MEFV) curves, which is a particularly prominent issue among children due to limited cooperation, especially those younger than 6 years old. • It is relatively difficult to differentiate between ventilatory dysfunction and poor cooperation when a slow start occurs in children; therefore, there is an urgent need for an objective indicator that is unaffected by ventilatory impairment to evaluate quality control of spirometry. What is New: • The initial angle β, which was introduced at the ascending limb of the MEFV curve in the present study, has a certain diagnostic value for poor-quality MEFV curves in children. • Angle β < 74.58° is a predictor of poor-quality MEFV curves, and its combination with FET < 4.91 s offers a higher diagnostic value.

Normative Reference Equations for Breathlessness Intensity during Incremental Cardiopulmonary Cycle Exercise Testing

Rationale: Cardiopulmonary exercise testing (CPET) is the gold standard to evaluate exertional breathlessness, a common and disabling symptom. However, the interpretation of breathlessness responses to CPET is limited by a scarcity of normative data. Objectives: We aimed to develop normative reference equations for breathlessness intensity (Borg 0-10 category ratio) response in men and women aged ⩾40 years during CPET, in relation to power output (watts), oxygen uptake, and minute ventilation. Methods: Analysis of ostensibly healthy people aged ⩾40 years undergoing symptom-limited incremental cycle CPET (10 W/min) in the CanCOLD (Canadian Cohort Obstructive Lung Disease) study. Participants had smoking histories <5 pack-years and normal lung function and exercise capacity. The probability of each Borg 0-10 category ratio breathlessness intensity rating by power output, oxygen uptake, and minute ventilation (as an absolute or a relative value [percentage of predicted maximum]) was predicted using ordinal multinomial logistic regression. Model performance was evaluated by fit, calibration, and discrimination (C statistic) and externally validated in an independent sample (n = 86) of healthy Canadian adults. Results: We included 156 participants (43% women) from CanCOLD; the mean age was 65 (range, 42-91) years, and the mean body mass index was 26.3 (standard deviation, 3.8) kg/m2. Reference equations were developed for women and men separately, accounting for age and/or body mass. Model performance was high across all equations, including in the validation sample (C statistic for men = 0.81-0.92, C statistic for women = 0.81-0.96). Conclusions: Normative reference equations are provided to compare exertional breathlessness intensity ratings among individuals or groups and to identify and quantify abnormal breathlessness responses (scores greater than the upper limit of normal) during CPET.

Severity-stratification of interstitial lung disease by deep learning enabled assessment and quantification of lesion indicators from HRCT images

BACKGROUND

Interstitial lung disease (ILD) represents a group of chronic heterogeneous diseases, and current clinical practice in assessment of ILD severity and progression mainly rely on the radiologist-based visual screening, which greatly restricts the accuracy of disease assessment due to the high inter- and intra-subjective observer variability.

OBJECTIVE

To solve these problems, in this work, we propose a deep learning driven framework that can assess and quantify lesion indicators and outcome the prediction of severity of ILD.

METHODS

In detail, we first present a convolutional neural network that can segment and quantify five types of lesions including HC, RO, GGO, CONS, and EMPH from HRCT of ILD patients, and then we conduct quantitative analysis to select the features related to ILD based on the segmented lesions and clinical data. Finally, a multivariate prediction model based on nomogram to predict the severity of ILD is established by combining multiple typical lesions.

RESULTS

Experimental results showed that three lesions of HC, RO, and GGO could accurately predict ILD staging independently or combined with other HRCT features. Based on the HRCT, the used multivariate model can achieve the highest AUC value of 0.755 for HC, and the lowest AUC value of 0.701 for RO in stage I, and obtain the highest AUC value of 0.803 for HC, and the lowest AUC value of 0.733 for RO in stage II. Additionally, our ILD scoring model could achieve an average accuracy of 0.812 (0.736 - 0.888) in predicting the severity of ILD via cross-validation.

CONCLUSIONS

In summary, our proposed method provides effective segmentation of ILD lesions by a comprehensive deep-learning approach and confirms its potential effectiveness in improving diagnostic accuracy for clinicians.

ERS technical standard: Global Lung Function Initiative reference values for exhaled nitric oxide fraction (F ENO50 )

BACKGROUND

Elevated exhaled nitric oxide fraction at a flow rate of 50 mL·s-1 (F ENO50 ) is an important indicator of T-helper 2-driven airway inflammation and may aid clinicians in the diagnosis and monitoring of asthma. This study aimed to derive Global Lung Function Initiative reference equations and the upper limit of normal for F ENO50 .

METHODS

Available individual F ENO50 data were collated and harmonised using consensus-derived variables and definitions. Data collected from individuals who met the harmonised definition of "healthy" were analysed using the generalised additive models of location, scale and shape (GAMLSS) technique.

RESULTS

Data were retrospectively collated from 34 782 individuals from 34 sites in 15 countries, of whom 8022 met the definition of healthy (19 sites, 11 countries). Overall, height, age and sex only explained 12% of the between-subject variability of F ENO50 (R2=0.12). F ENO device was neccessary as a predictor of F ENO50 , such that the healthy range of values and the upper limit of normal varied depending on which device was used. The range of F ENO50 values observed in healthy individuals was also very wide, and the heterogeneity was partially explained by the device used. When analysing a subset of data in which F ENO50 was measured using the same device and a stricter definition of health (n=1027), between-site heterogeneity remained.

CONCLUSION

Available F ENO50 data collected from different sites using different protocols and devices were too variable to develop a single all-age reference equation. Further standardisation of F ENO devices and measurement are required before population reference values might be derived.

Longitudinal assessment of lung function in Swiss childhood cancer survivors-A multicenter cohort study

OBJECTIVE

Childhood cancer survivors are at risk for pulmonary morbidity due to exposure to lung-toxic treatments, including specific chemotherapeutics, radiotherapy, and surgery. Longitudinal data on lung function and its change over time are scarce. We investigated lung function trajectories in survivors over time and the association with lung-toxic treatments.

METHODS

This retrospective, multicenter cohort study included Swiss survivors diagnosed between 1990 and 2013 and exposed to lung-toxic chemotherapeutics or thoracic radiotherapy. Pulmonary function tests (PFTs), including forced expiration volume in the first second (FEV1), forced vital capacity (FVC), FEV1/FVC, total lung capacity,  and diffusion capacity of the lung for carbon monoxide, were obtained from hospital charts. We calculated z-scores and percentage predicted, described lung function over time, and determined risk factors for change in FEV1 and FVC using multivariable linear regression.

RESULTS

We included 790 PFTs from 183 survivors, with a median age of 12 years at diagnosis and 5.5 years of follow-up. Most common diagnosis was lymphoma (55%). Half (49%) of survivors had at least one abnormal pulmonary function parameter, mainly restrictive (22%). Trajectories of FEV1 and FVC started at z-scores of -1.5 at diagnosis and remained low throughout follow-up. Survivors treated with thoracic surgery started particularly low, with an FEV1 of -1.08 z-scores (-2.02 to -0.15) and an FVC of -1.42 z-scores (-2.27 to -0.57) compared to those without surgery.

CONCLUSION

Reduced pulmonary function was frequent but mainly of mild to moderate severity. Nevertheless, more research and long-term surveillance of this vulnerable population is needed.

Two is better than one: the double diffusion technique in classifying heart failure

Background

Heart failure (HF) is a chronic condition in which the heart does not pump enough blood to meet the body's demands. Diffusing capacity of the lung for nitric oxide (DLNO) and carbon monoxide (DLCO) may be used to classify patients with HF, as DLNO and DLCO are lung function measurements that reflect pulmonary gas exchange. Our objectives were to determine 1) if DLNO added to DLCO testing predicts HF better than DLCO alone and 2) whether the binary classification of HF is better when DLNO z-scores are combined with DLCO z-scores than using DLCO z-scores alone.

Methods

This was a retrospective secondary data analysis in 140 New York Heart Association Class II HF patients (ejection fraction <40%) and 50 patients without HF. z-scores for DLNO, DLCO and DLNO+DLCO were created from reference equations from three articles. The model with the lowest Bayesian Information Criterion was the best predictive model. Binary HF classification was evaluated with the Matthews Correlation Coefficient (MCC).

Results

The top two of 12 models were combined z-score models. The highest MCC (0.51) was from combined z-score models. At most, only 32% of the variance in the odds of having HF was explained by combined z-scores.

Conclusions

Combined z-scores explained 32% of the variation in the likelihood of an individual having HF, which was higher than models using DLNO or DLCO z-scores alone. Combined z-score models had a moderate ability to classify patients with HF. We recommend using the NO-CO double diffusion technique to assess gas exchange impairment in those suspected of HF.

Periodontitis is associated with airflow obstruction in the Malmö Offspring Dental Study

AIM

To investigate the association between periodontitis and lung function in the Malmö Offspring Dental Study.

MATERIALS AND METHODS

In all 1001 individuals (49.9% female, mean age: 44.6) from Malmö Offspring Dental Study were included. Periodontitis was assessed by a full-mouth examination protocol including bleeding on probing and classified according to the American Academy of Periodontology/Center for Disease Control definitions. Forced expiratory volume in 1 s (FEV1 ) and forced vital capacity (FVC) were expressed as absolute values and %predicted according to Global Lung Function Initiative reference values. FEV1 , FVC and FEV1 /FVC were analysed in relation to periodontal status using linear regression.

RESULTS

Severe periodontitis was found in 7% of the population. Adjusted regression models showed significant associations between lung function and severe periodontitis with 2.1 unit lower FEV1 /FVC ratio (95% CI: -3.91, -0.23) and odds ratio (adjusted) of 2.56 (95% CI: 1.40, 4.75, p = .003) for airflow obstruction (FEV1 /FVC less than the lower limit of normal) if having severe periodontitis. Lower values of %predicted FEV1 and %predicted FVC, but not FEV1 /FVC, were found in individuals with >25% bleeding on probing.

CONCLUSIONS

Severe periodontitis was associated with lower FEV1 /FVC ratio and airflow obstruction in the present cohort. More large-scale prospective studies and intervention studies are required for a comprehensive evaluation.

Long- versus short-duration systemic corticosteroid regimens for acute exacerbations of COPD: A systematic review and meta-analysis of randomized trials and cohort studies

While systemic corticosteroids quicken patient recovery during acute exacerbations of COPD, they also have many adverse effects. The optimal duration of corticosteroid administration remains uncertain. We performed a systematic review and meta-analysis to compare patient outcomes between short- (≤7 days) and long- (>7 days) corticosteroid regimens in adults with acute exacerbations of COPD. MEDLINE, EMBASE, CENTRAL, and hand searches were used to identify eligible studies. Risk of bias was assessed using the Cochrane RoB 2.0 tool and ROBINS-I. Data were summarized as ORs (odds ratios) or MDs (mean differences) whenever possible and qualitatively described otherwise. A total of 11532 participants from eight RCTs and three retrospective cohort studies were included, with 1296 from seven RCTs and two cohort studies eligible for meta-analyses. Heterogeneity was present in the methodology and settings of the studies. The OR (using short duration as the treatment arm) for mortality was 0.76 (95% CI = 0.40-1.44, n = 1055). The MD for hospital length-of-stay was -0.91 days (95% CI = -1.81--0.02 days, n = 421). The OR for re-exacerbations was 1.31 (95% CI = 0.90-1.90, n = 552). The OR for hyperglycemia was 0.90 (95% CI = 0.60-1.33, n = 423). The OR for infection incidence was 0.96 (95% CI = 0.59-1.156, n = 389). The MD for one-second forced expiratory volume change was -18.40 mL (95% CI = -111.80-75.01 mL, n = 161). The RCTs generally had low or unclear risks of bias, while the cohort studies had serious or moderate risks of bias. Our meta-analyses were affected by imprecision due to insufficient data. Some heterogeneity was present in the results, suggesting population, setting, and treatment details are potential prognostic factors. Our evidence suggests that short-duration treatments are not worse than long-duration treatments in moderate/severe exacerbations and may lead to considerably better outcomes in milder exacerbations. This supports the current GOLD guidelines. Trial registration: Our protocol is registered in PROSPERO: CRD42023374410.

Beyond the Acute Phase: Long-Term Impact of COVID-19 on Functional Capacity and Prothrombotic Risk-A Pilot Study

Background and Objectives: Assessment of the prothrombotic, proinflammatory, and functional status of a cohort of COVID-19 patients at least two years after the acute infection to identify parameters with potential therapeutic and prognostic value. Materials and Methods: We conducted a retrospective, descriptive study that included 117 consecutive patients admitted to Iasi Pulmonary Rehabilitation Clinic for reassessment and a rehabilitation program at least two years after a COVID-19 infection. The cohort was divided into two groups based on the presence (n = 49) or absence (n = 68) of pulmonary fibrosis, documented through high-resolution computer tomography. Results: The cohort comprises 117 patients, 69.23% females, with a mean age of 65.74 ± 10.19 years and abnormal body mass index (31.42 ± 5.71 kg/m2). Patients with pulmonary fibrosis have significantly higher levels of C-reactive protein (CRP) (p < 0.05), WBC (7.45 ± 7.86/mm3 vs. 9.18 ± 17.24/mm3, p = 0.053), neutrophils (4.68 ± 7.88/mm3 vs. 9.07 ± 17.44/mm3, p < 0.05), mean platelet volume (MPV) (7.22 ± 0.93 vs. 10.25 ± 0.86 fL, p < 0.05), lactate dehydrogenase (p < 0.05), and D-dimers (p < 0.05), but not ferritin (p = 0.470), reflecting the chronic proinflammatory and prothrombotic status. Additionally, patients with associated pulmonary fibrosis had a higher mean heart rate (p < 0.05) and corrected QT interval (p < 0.05). D-dimers were strongly and negatively correlated with diffusion capacity corrected for hemoglobin (DLCO corr), and ROC analysis showed that the persistence of high D-dimers values is a predictor for low DLCO values (ROC analysis: area under the curve of 0.772, p < 0.001). The results of pulmonary function tests (spirometry, body plethysmography) and the 6-minute walk test demonstrated no significant difference between groups, without notable impairment within either group. Conclusions: Patients with COVID-19-related pulmonary fibrosis have a persistent long-term proinflammatory, prothrombotic status, despite the functional recovery. The persistence of elevated D-dimer levels could emerge as a predictive factor associated with impaired DLCO.

The long-term effects of COVID-19 on pulmonary status and quality of life

Background

Few studies have looked at how SARS-CoV-2 affects pulmonary function, exercise capacity, and health-related quality of life over time. The purpose of this study was to evaluate these characteristics in post COVID-19 subjects 1 year after recovery.

Methods

The study included two groups. The case group included post COVID-19 subjects who had recovered after a year, and the control group included healthy participants who had never tested positive for COVID-19.

Results

The study screened 90 participants, 42 of whom met the eligibility criteria. The findings revealed that the majority of post COVID-19 subjects had relatively normal lung function 1-year post-recovery. A significant reduction in DLCO (B/P%) was observed in the case group vs. control. The exercise capacity test revealed a clinically significant difference in distance walked and a significant difference in the dyspnea post-walk test in the case group compared to the control group. The case group's health-related quality of life domain scores were significantly affected in terms of energy/fatigue, general health, and physical function.

Conclusions

The post COVID-19 subjects were shown to have well-preserved lung function after 1 year. However, some degree of impairment in diffusion capacity, exercise capacity, and health-related quality of life remained.

Exercise testing for young athletes

With increasing competitiveness across the sporting landscape, there is a need for more research into monitoring and managing the young athlete, as the needs of a young athlete are vastly different to those of an older athlete who is already established in their respective sport. As the age of sports specialisation seems to decrease, exercise testing in the younger cohort of athletes is crucial for safety and long-term success. This article provides a comprehensive summary of available testing and monitoring methods that can be used to assist young athletes as they mature and attempt to excel in their chosen sport.

Anticipating undiagnosed asthma in symptomatic adults with normal pre- and post-bronchodilator spirometry: a decision tool for bronchial challenge testing

BACKGROUND

Some patients with asthma demonstrate normal spirometry and remain undiagnosed without further testing.

OBJECTIVE

To determine clinical predictors of asthma in symptomatic adults with normal spirometry, and to generate a tool to help clinicians decide who should undergo bronchial challenge testing (BCT).

METHODS

Using random-digit dialling and population-based case-finding, we recruited adults from the community with respiratory symptoms and no previous history of diagnosed lung disease. Participants with normal pre- and post-bronchodilator spirometry subsequently underwent BCT. Asthma was diagnosed in those with symptoms and a methacholine provocative concentration (PC20) of < 8 mg/ml. Sputum and blood eosinophils, and exhaled nitric oxide were measured. Univariate analyses identified potentially predictive variables, which were then used to construct a multivariable logistic regression model to predict asthma. Model sensitivity, specificity, and area under the receiver operating curve (AUC) were calculated.

RESULTS

Of 132 symptomatic individuals with normal spirometry, 34 (26%) had asthma. Of those ultimately diagnosed with asthma, 33 (97%) answered 'yes' to a question asking whether they experienced cough, chest tightness or wheezing provoked by exercise or cold air. Other univariate predictors of asthma included female sex, pre-bronchodilator FEV1 percentage predicted, and percent positive change in FEV1 post bronchodilator. A multivariable model containing these predictive variables yielded an AUC of 0.82 (95% CI: 0.72-0.91), a sensitivity of 82%, and a specificity of 66%. The model was used to construct a nomogram to advise clinicians which patients should be prioritized for BCT.

CONCLUSIONS

Four readily available patient characteristics demonstrated a high sensitivity and AUC for predicting undiagnosed asthma in symptomatic adults with normal pre- and post-bronchodilator spirometry. These characteristics can potentially help clinicians to decide which individuals with normal spirometry should be investigated with bronchial challenge testing. However, further prospective validation of our decision tool is required.

Impact of the metabolic syndrome on cardiopulmonary morbidity and mortality in individuals with lung function impairment: a prospective cohort study of the Danish general population

Background

Whether the metabolic syndrome plays a role for the prognosis of individuals with lung function impairment (preserved ratio impaired spirometry (PRISm) or airflow limitation) is unclear. We hypothesised that the metabolic syndrome in individuals with lung function impairment is associated with increased cardiopulmonary morbidity and mortality.

Methods

The Copenhagen General Population Study was initiated in 2003 based on a random sample of white men and women aged 20-100 years drawn from the Danish general population. The risk of ischemic heart disease/heart failure, respiratory disease, and all-cause mortality was analysed with Cox models adjusted for age, sex, current smoking, and asthma during 15 years of follow-up.

Findings

Among 106,845 adults, 86,159 had normal lung function, 6126 had PRISm, and 14,560 had airflow limitation. We observed 10,448 hospital admissions for ischemic heart disease/heart failure, 21,140 for respiratory disease, and 11,125 deaths. Individuals with versus individuals without the metabolic syndrome generally had higher 5-year absolute risk of all outcomes, including within those with normal lung function, mild-moderate-severe PRISm, and very mild-mild-moderate-severe airflow limitation alike. Compared to individuals without the metabolic syndrome and with normal lung function, those with both the metabolic syndrome and severe PRISm had hazard ratios of 3.74 (95% CI: 2.53-5.55; p < 0.0001) for ischemic heart disease/heart failure, 5.02 (3.85-6.55; p < 0.0001) for respiratory disease, and 5.32 (3.76-7.54; p < 0.0001) for all-cause mortality. Corresponding hazard ratios in those with both the metabolic syndrome and severe airflow limitation were 2.89 (2.34-3.58; p < 0.0001) for ischemic heart disease/heart failure, 5.98 (5.28-6.78; p < 0.0001) for respiratory disease, and 4.16 (3.50-4.95; p < 0.0001) for all-cause mortality, respectively. The metabolic syndrome explained 13% and 27% of the influence of PRISm or airflow limitation on ischemic heart disease/heart failure and all-cause mortality.

Interpretation

The metabolic syndrome conferred increased risk of cardiopulmonary morbidity and mortality at all levels of lung function impairment.

Funding

Danish Lung Foundation, Danish Heart Foundation, Capital Region of Copenhagen, and Boehringer Ingelheim. JV is supported by the NIHR Manchester BRC.