Tracking Real-World Physical Activity in Chronic Obstructive Pulmonary Disease Over One Year: Results from a Monocentric, Prospective, Observational Cohort Study.

Introduction: Lung function constraints and comorbidities such as coronary heart disease, sarcopenia, and mood disorders make chronic obstructive pulmonary disease (COPD) patients avoid physical activity (PA). However, PA represents an important pillar of COPD management and is explicitly recommended by professional associations to enhance physical functioning and positively modulate disease progression. Methods: In this monocentric, prospective, observational feasibility study, it was our primary objective to investigate the association between PA and the evolution of the COPD assessment test (CAT) and the occurrence of acute exacerbations of COPD (AECOPD), respectively. To this end, we equipped 42 COPD patients with an activity tracking wearable and telemonitored their daily PA levels over one year using a dedicated web-based interface. Patients additionally provided weekly CAT scores using the same telehealth platform and came in for 3 study visits to assess functional parameters and biochemical markers related to nutrition and inflammation. Results: A principal study finding was that PA was inversely associated with CAT score (drop of 0.21 points associated with an increase of 1000 daily steps, p = 0.004), and that the 50% of patients with higher PA levels showed less CAT score progression over time (0.42 points per year) than the 50% of patients with lower PA levels (3.26 points per year) (p < 0.001). In addition, higher PA levels were significantly associated with a lower likelihood of experiencing a moderate-to-severe AECOPD (31% risk reduction associated with an increase of 1000 daily steps, p = 0.0097). Discussion: Our study demonstrates the relevance of PA for key COPD outcome metrics in a real-world setting and underpins the importance of PA for COPD self-management in everyday life. Our study paves the way for future intervention trials to prospectively identify medically relevant PA thresholds and establish training recommendations for different patient subgroups.

The Real-World Efficacy of Fixed Triple Inhalation Therapy in the Treatment of Moderate COPD Patients (RATIONALE Study).

Purpose: COPD affects more than 300 million people worldwide, requiring inhalation treatment. Novel triple formulations of ICS, LABAs and LAMAs are becoming the mainstay of treatment, however there is still a lack of clinical evidence for personalized therapy. Patients and Methods: RATIONALE was a non-interventional, prospective, 52 week study, assessing the effectiveness of beclometasone/formoterol/glycopyrronium-bromide (BDP/FF/G), in symptomatic COPD patients, with moderate airflow obstruction. The study included 4 visits, where data on demographic parameters, exacerbations, symptoms, quality of life (based on the EQ-5D-3L questionnaire) and lung function were collected. Data on adherence to treatment, based on prescriptions filled was collected from the database of the National Health Insurance Fund, with the patients' consent. The primary objective was the change of adherence to treatment during the study, compared to baseline. Results: Altogether 613 patients had been enrolled. Their average age was 64.56 years and 50.5% were female. The average CAT score was 20.86, and most patients had suffered minimum one exacerbation (82.2%). Average FEV1 was 59.6%. Most patients had some limitation in one or more dimensions of EQ-5D-3L, with an average visual analogue scale score (VAS) of 60.31. After 12 months of treatment, adherence improved significantly - proportion of patients in the highest adherence group increased from 29.8% to 69.7% (p<0.001). The average CAT score improved by 7.02 points (95% CI 5.82-8.21, p<0.001). There was a significant improvement in all dimensions of EQ-5D-3L, with an average increase of 17.91 (95% CI 16.51-19.31, p< 0.001) points in the VAS score. Exacerbation frequency also decreased significantly. Conclusion: Although limitations of observational studies are present, we observed that early introduction of fixed triple combination results in a marked improvement in adherence to treatment, symptom scores, exacerbation frequency and quality of life. The optimal choice of treatment is crucial for reaching the highest possible adherence.

Processing of Sedentary Time and Its Reference Equation in Patients with COPD.

Purpose: Sedentary time (ST) is associated with mortality independent of moderate-to-vigorous physical activity in patients with COPD. The proper processing methods for the measurement data and factors related to ST are still unknown. We investigated several conditions for determining the proper processing of ST accelerometric data and created a reference equation for ST using ST-related factors. Patients and Methods: In Study 1, we evaluated the minimum required number of days to obtain repeatability at different measurement times and assessed the effects of rainy days or weekend days on ST in patients with COPD. In Study 2, we detected the ST-related factors among 28 parameters and created a reference equation for ST using the detected factors. Results: In Study 1, 38 patients with stable COPD were analyzed. The minimum number of days required for repeatability was 3 for 8-h wearing and 2 for 10-h wearing. The ST was significantly prolonged on rainy days, but not on weekends. In Study 2, 216 patients with stable COPD were analyzed. BMI, FEV1%pred, 6MWD, and mMRC were detected as ST-related factors, and a reference equation could be created using these four factors. The equation was validated for patients whose ST was ≥ 6 h. Conclusion: By using properly processed measurement data of ST, we created a reference equation for assessing ST that is expected to be useful for providing individual guidance on the shortening of ST to patients with COPD.

When measuring sedentary time (ST) objectively, we should recognize that the minimum required number of days is three and that ST is prolonged on rainy days. The reference equation for ST could be created using four ST-related factors. It might serve as a guide for shortening ST in COPD.

Subclinical impairment of the left atrium is associated with MRI-based lung volume but not with parameters from pulmonary function testing.

Left atrial (LA) physiology and hemodynamics are intimately connected to cardiac and lung function in health and disease. This study examined the relationship between MRI-based left atrial (LA) size and function with MRI-based lung volume and pulmonary function testing (PFT) parameters in the population-based KORA study cohort of 400 participants without overt cardiovascular disease. MRI quantification assessed LA size/function in sequences with and without ECG synchronization, alongside lung volume. Regression analysis explored the relationship of LA with MRI lung volume and PFT parameters. Among 378 participants (average age 56.3 ± 9.2 years; 42.3% women), non-gated LA size averaged 16.8 cm2, while maximal and minimal LA size from gated measurements were 19.6 cm2 and 11.9 cm2 respectively. The average MRI-derived lung volume was 4.0 L, with PFT showing a total lung capacity of 6.2 L, residual lung volume of 2.1 L, and forced vital capacity of 4.1 L. Multivariate regression analysis, adjusted for age, gender, and cardiovascular risk factors, revealed an inverse association between maximum LA size, non-gated LA, and LA area fraction with lung volume (ß = - 0.03, p = 0.006; ß = - 0.03, p = 0.021; ß = - 0.01, p = 0.012), with no significant association with PFT parameters. This suggests that MRI-based assessment may offer greater sensitivity in detecting subclinical LA impairment than PFT.

Characteristics of lung resistance and elastance associated with tracheal stenosis and intrapulmonary airway narrowing in ex vivo sheep lungs.

BACKGROUND: Understanding the characteristics of pulmonary resistance and elastance in relation to the location of airway narrowing, e.g., tracheal stenosis vs. intrapulmonary airway obstruction, will help us understand lung function characteristics and mechanisms related to different airway diseases. METHODS: In this study, we used ex vivo sheep lungs as a model to measure lung resistance and elastance across a range of transpulmonary pressures (5-30 cmH2O) and ventilation frequencies (0.125-2 Hz). We established two tracheal stenosis models by inserting plastic tubes into the tracheas, representing mild (71.8% lumen area reduction) and severe (92.1%) obstructions. For intrapulmonary airway obstruction, we induced airway narrowing by challenging the lung with acetylcholine (ACh). RESULTS: We found a pattern change in the lung resistance and apparent lung elastance as functions of ventilation frequency that depended on the transpulmonary pressure (or lung volume). At a transpulmonary pressure of 10 cmH2O, lung resistance increased with ventilation frequency in severe tracheal stenosis, whereas in ACh-induced airway narrowing the opposite occurred. Furthermore, apparent lung elastance at 10 cmH2O decreased with increasing ventilation frequency in severe tracheal stenosis whereas in ACh-induced airway narrowing the opposite occurred. Flow-volume analysis revealed that the flow amplitude was much sensitive to ventilation frequency in tracheal stenosis than it was in ACh induced airway constriction. CONCLUSIONS: Results from this study suggest that lung resistance and apparent elastance measured at 10 cmH2O over the frequency range of 0.125-2 Hz can differentiate tracheal stenosis vs. intrapulmonary airway narrowing in ex vivo sheep lungs.

Efficacy and safety of step-by-step Baduanjin exercise based on doctor-nurse-patient integration mode for pulmonary rehabilitation in patients after lobectomy due to pulmonary tuberculosis: a randomized controlled clinical trial.

BACKGROUND: Some pulmonary tuberculosis patients may require lung resection surgery. Postoperative pulmonary rehabilitation is essential to restore the lung function and maintain quality of life. We aimed to study the pulmonary rehabilitation outcomes and complications of step-by-step Baduanjin exercise under a doctor-nurse-patient integration mode in patients after lobectomy due to pulmonary tuberculosis. METHODS: We performed a randomized controlled clinical trial in patients undergoing lobectomy due to pulmonary tuberculosis between September 2017 and August 2021. Eligible patients were randomly assigned into the control group or interventional group. The control group received routine postoperative care. The interventional group received step-by-step Baduanjin exercise based on the doctor-nurse-patient integration mode in addition to the routine care. The primary outcomes were the pulmonary functions, including forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), and FEV1/FVC. The secondary outcomes were the maximum walking distance in a 6-min walk test and postoperative pulmonary complications, including atelectasis, pneumonia, and respiratory failure. RESULTS: A total of 100 patients were enrolled into the study, with 50 patients in the control and interventional groups. There were 60 female patients (60%). The mean patient age was 37.9 (± 2.8) years old. At the one- and two-month postoperative follow-ups, pulmonary function tests showed statistically significantly better performances in FEV1/prediction, FVC/prediction, and FEV1/FVC in the interventional group than the control group. The 6-min walk test also revealed longer walking distances in the interventional group than the control group. There were no statistically significant differences in postoperative complications between the two groups. CONCLUSIONS: A step-by-step Baduanjin exercise regimen under the doctor-nurse-patient integration mode could safely improve pulmonary rehabilitation in patients after lobectomy due to pulmonary tuberculosis.

Association between dietary choline intake and asthma and pulmonary inflammation and lung function: NHANES analysis 2009-2018.

BACKGROUND: Asthma is a chronic inflammatory condition, and choline may alleviate airway inflammation and oxidative stress but studies on the association between dietary choline and asthma remain limited. The purpose of this study is to investigate the associations between dietary choline intake and asthma, as well as pulmonary inflammation and lung function in children and adults. METHODS: In our research, we employed the data of the National Health and Nutrition Examination Survey (NHANES) from 2009 to 2018, including 7,104 children and 16,580 adults. We used fractional exhaled nitric oxide (FENO) to assess pulmonary inflammation and forced expiratory volume in one second (FEV1), forced vital capacity (FVC), the FEV1/FVC ratio, peak expiratory flow rate (PEF), predicted FEV1% and predicted FVC% to assess lung function. Binary logistic regression, linear regression, and the restricted cubic splines were used to analyze the associations between dietary choline intake and asthma and pulmonary inflammation and lung function. RESULTS: In children, we observed the positive associations between the natural logarithmic transformation of choline (ln-choline) and ln-FEV1 [ ß:0.011; 95%CI: (0.004,0.018)] and ln-FVC [ ß:0.009; 95%CI: (0.002,0.016)]. In adult males, the ln-choline was positively associated with ln-FEV1[ ß:0.018; 95%CI: (0.011,0.024)], ln-FVC [ ß:0.020; 95%CI: (0.014,0.026)], ln-PEF [ ß:0.014; 95%CI: (0.007,0.022)], ln-predicted FEV1% [ ß: 0.007; 95%CI: (0.001, 0.013)] and ln-predicted FVC%[ ß: 0.010; 95%CI: (0.005, 0.015)] and negatively associated with FENO [ ß: -0.029; 95%CI: (-0.049, -0.009)]. In unadjusted and partially adjusted models, adult females with ln-choline in the highest quartile had 25.2% (95%CI:9.4-38.3%) and 23.8% (95%CI:7.6-37.1%) decreased odds of asthma compared to those with the lowest quartile group. In the dose-response relationships of dietary choline and pulmonary inflammation and lung function indicators in adults, there existed threshold and saturation effects. CONCLUSION: The associations between dietary choline and lung function indicators such as FEV1 and FVC are positive in children and adults. The association between dietary choline and pulmonary inflammation is negative only in adults.

Effect of abatacept versus conventional synthetic disease modifying anti-rheumatic drugs on rheumatoid arthritis-associated interstitial lung disease.

BACKGROUND/AIMS: To compare the effects of abatacept and conventional synthetic disease modifying anti-rheumatic drugs (csDMARDs) on the progression and development of rheumatoid arthritis-associated interstitial lung disease (RA-ILD). METHODS: This multi-center retrospective study included RA patients receiving abatacept or csDMARDs who underwent at least two pulmonary function tests and/or chest high-resolution computed tomography (HRCT). We compared the following outcomes between the groups: progression of RA-ILD, development of new ILD in RA patients without ILD at baseline, 28-joint Disease Activity Score with the erythrocyte sedimentation rate (DAS28-ESR), and safety. Longitudinal changes were compared between the groups by using a generalized estimating equation. RESULTS: The study included 123 patients who were treated with abatacept (n = 59) or csDMARDs (n = 64). Nineteen (32.2%) and 38 (59.4%) patients treated with abatacept and csDMARDs, respectively, presented with RA-ILD at baseline. Newly developed ILD occurred in one patient receiving triple csDMARDs for 32 months. Among patients with RA-ILD at baseline, ILD progressed in 21.1% of cases treated with abatacept and 34.2% of cases treated with csDMARDs during a median 21-month follow-up. Longitudinal changes in forced vital capacity and diffusing capacity for carbon monoxide were comparable between the two groups. However, the abatacept group showed a more significant decrease in DAS28-ESR and glucocorticoid doses than csDMARDs group during the follow-up. The safety of both regimens was comparable. CONCLUSION: Abatacept and csDMARDs showed comparable effects on the development and stabilization of RA-ILD. Nevertheless, compared to csDMARDs, abatacept demonstrated a significant improvement in disease activity and led to reduced glucocorticoid use.

Idiopathic Pulmonary Fibrosis: Review of Current Knowledge.

Idiopathic pulmonary fibrosis (IPF) is a severe and currently incurable disease that is associated with irreversible fibrotic remodeling of the lung parenchyma. Pathological remodeling of the lung leads to damage of the alveolo-capillary barrier. There is a reduction in the diffusing capacity of the lungs for respiratory gases. Later, changes in the mechanical properties of lung tissue occur - their compliance decreases and respiratory work increases. Impaired respiratory gases exchange with restrictive ventilatory failure lead to tissue hypoxia and muscle weakness. Progressive respiratory insufficiency develops. The triggers of fibrotic remodeling of the lung are currently unknown, as are the pathomechanisms that keep this process active. IPF can only be slowed pharmacologically, not reversed. It is therefore very important to start its treatment as soon as possible. Early detection of IPF patients requires a multidisciplinary approach. Diagnosis, treatment initiation, and monitoring in specialized centers offer the best chance of slowing disease progression, enhancing quality of life, and extending patient survival. In addition to antifibrotic therapy, good lifestyle management, maintenance of physical fitness and treatment of associated chronic diseases such as diabetes and cardiac comorbidities are important. Lung transplantation is an option for some patients with IPF. This is a challenging treatment modality, requiring close collaboration with transplant centers and expert selection of suitable candidates, influenced, among other things, by the availability of suitable donor lungs. Our article aims to provide current information about IPF, focusing on its functional consequences and clinical manifestation. We discuss the molecular and cellular mechanisms potentially involved in IPF development, as well as the morphological changes observed in lung biopsies and high-resolution computed tomography (HRCT) images. Finally, we summarize the existing treatment options. Key words: Idiopathic pulmonary fibrosis, Lung biopsy, HRCT, Antifibrotic therapy, Lung transplantation.

Inverted U-Shaped relationship Between Systemic Immune-Inflammation Index and Pulmonary Function: A Large Population-Based Study in US Adults.

Background: Systemic immune-inflammation index (SII) is a novel comprehensive inflammatory marker. Inflammation is associated with impaired lung function. We aimed to explore the possible relationship between SII and lung function to examine the potential of SII in predicting lung function decline. Methods: A cross-sectional survey was conducted using the data of the NHANES from 2007 to 2012. Multiple linear regression models were used to analyze the linear relationship between SII and pulmonary functions. Sensitivity analyses, subgroup analyses, and interaction tests were used to examine the robustness of this relationship across populations. Fitted smooth curves and threshold effect analysis were used to describe the nonlinear relationships. Results: A total of 10,125 patients were included in this study. After adjusting for all covariates, multiple linear regression model analysis showed that high Log2-SII level was significantly associated with decreased FVC(ß, -23.4061; 95% CI, -42.2805- -4.5317), FEV1(ß, -46.7730; 95% CI, -63.3371- -30.2089), FEV1%(ß, -0.7923; 95% CI, -1.1635- -0.4211), FEV1/FVC(ß, -0.6366; 95% CI, -0.8328- -0.4404) and PEF(ß, -121.4468; 95% CI,-164.1939- -78.6998). The negative correlation between Log2-SII and pulmonary function indexes remained stable in trend test and stratified analysis. Inverted U-shaped relationships between Log2-SII and FVC, FEV1, FEV1%, and PEF were observed, while a negative linear correlation existed between FEV1/FVC and Log2-SII. The cutoff values of the nonlinear relationship between Log2-SII and FVC, FEV1, FEV1%, PEF were 8.3736, 8.0688, 8.3745, and 8.5255, respectively. When SII exceeded the critical value, the lung function decreased significantly. Conclusion: This study found a close correlation between SII and pulmonary function indicators. This study investigated the SII threshold when lung functions began to decline in the overall population. SII may become a promising serological indicator for predicting lung function decline. However, prospective studies were needed further to establish the causal relationship between these two factors.

Causal Relationship Between Gut Microbiota and Chronic Obstructive Pulmonary Disease: A Bidirectional Two-Sample Mendelian Randomization Study.

Background: The associations between gut microbiota and chronic obstructive pulmonary disease (COPD) have gained increasing attention and research interest among scholars. However, it remains unclear whether gut microbiota serves as a causal factor for COPD or if it is a consequence of the disease. Therefore, we investigated the causal relationship between COPD and gut microbiota, with intention of providing novel insights and references for clinical diagnosis and treatment. Methods: Based on the genome-wide association study (GWAS) data, we employed MR-Egger regression, random-effects inverse variance-weighted (IVW) method, and weighted median method for bidirectional Mendelian randomization (MR) analysis. We conducted Cochran's Q test for heterogeneity assessment and performed multivariable analysis, sensitivity analysis, and heterogeneity testing to validate the reliability and stability of results. Results: Utilizing MR analysis, mainly employing the IVW method, we detected a collective of 11 gut microbiota species that exhibited associations with COPD. Among them, Bacteroidia, family XIII, Clostridium innocuum group, Barnesiella, Collinsella, Lachnospiraceae NK4A136 group, Lachnospiraceae UCG004, Lachnospiraceae UCG010, and Bacteroidales were found to be protective factors for COPD. On the other hand, Holdemanella and Marvinbryantia were identified as risk factors for COPD. Individuals with elevated levels of Holdemanella exhibited a 1.141-fold higher risk of developing COPD compared to their healthy counterparts, and those with increased levels of Marvinbryantia had a 1.154-fold higher risk. Reverse MR analysis yielded no evidence indicating a causal relationship between gut microbiota and COPD occurrence. Conclusion: Our study established a causal link between 11 specific gut microbiota species and COPD, offering novel insights and valuable references for targeted therapies in the clinical management of COPD. However, our results were mainly based on the analysis of database, and further clinical studies are needed to clarify the effects of gut microbiota on COPD and its specific protective mechanism.

Association between acute exacerbation and progressive pulmonary fibrosis in interstitial lung disease: a retrospective cohort study.

BACKGROUND: Acute exacerbation (AE) refers to rapidly progressive respiratory deterioration in the clinical course of interstitial lung disease (ILD). Progressive pulmonary fibrosis (PPF) is the chronic progressive phenotype of ILD. No study has investigated the relationship between AE and PPF in ILD. OBJECTIVES: We aimed to determine the association between AE and PPF in ILD patients. DESIGN: A retrospective cohort study. METHODS: A total of 414 patients hospitalised for ILD were included in our study. The clinical presentations, radiographic features and laboratory findings of the patients were reviewed. RESULTS: AE was present in 120 (29.0%) ILD patients and was associated with a higher risk of death than non-AE patients in the whole cohort (HR 2.893; 95% CI, 1.847-4.529; p < 0.001). However, the significant difference disappeared when stratified by PPF (HR 1.192; 95% CI, 0.633-2.247; p = 0.586) and non-PPF (HR 1.113; 95% CI, 0.384-3.223; p = 0.844). In addition, the adverse effect of PPF on prognosis remained consistent in both AE and non-AE patients. Multivariable logistic regression analysis showed that compared with non-PPF patients, only age was a risk factor for PPF in AE-ILD, while the risk factors for PPF in the non-AE group were age, definite usual interstitial pneumonia and mediastinal lymph node enlargement. CONCLUSION: In the context of ILD, both AE and PPF were found to be associated with poor prognosis. However, the adverse effect of AE on prognosis disappeared when PPF was considered as a stratification feature, whereas the adverse effect of PPF on prognosis persisted in both AE and non-AE individuals. Therefore, it is important to investigate effective strategies to prevent disease progression after AE. Increased recognition and attention to PPF and early antifibrotic therapy at the appropriate time is also warranted.

Association between acute exacerbation and progressive pulmonary fibrosis in interstitial lung diseaseWhy was the study done? Acute exacerbation (AE) is an acute respiratory worsening of interstitial lung disease (ILD). Progressive pulmonary fibrosis (PPF) is a chronic progressive-fibrosing form of ILD. The relationship between AE and PPF in ILD remained unclear. We aimed to determine the association between AE and PPF in ILD patients.What did the researchers do? The researchers studied 414 patients with ILD to see how AE and PPF affect the outcome of ILD and explored the risk factors for PPF in ILD.What did the researchers find? AE was present in 120 (29.0%) ILD patients and was associated with higher risk of death than non-AE patients in the whole cohort. However, the significant difference disappeared when stratified by PPF and non-PPF. In addition, the adverse effect of PPF on prognosis remained consistent in both AE and non-AE patients. In AE-ILD patients, age was the only risk factor for PPF. In the non-AE group, age, definite usual interstitial pneumonia and mediastinal lymph node enlargement were risk factors for PPF.What do the findings mean? The findings suggest that it is important to investigate effective strategies to prevent disease progression after AE. Increased recognition and attention to PPF and early antifibrotic therapy at the appropriate time is also necessary.

Effect of perioperative sigh ventilation on postoperative hypoxemia and pulmonary complications after on-pump cardiac surgery (E-SIGHT): study protocol for a randomized controlled trial.

BACKGROUND: Postoperative hypoxemia and pulmonary complications remain a frequent event after on-pump cardiac surgery and mostly characterized by pulmonary atelectasis. Surfactant dysfunction or hyposecretion happens prior to atelectasis formation, and sigh represents the strongest stimulus for surfactant secretion. The role of sigh breaths added to conventional lung protective ventilation in reducing postoperative hypoxemia and pulmonary complications among cardiac surgery is unknown. METHODS: The perioperative sigh ventilation in cardiac surgery (E-SIGHT) trial is a single-center, two-arm, randomized controlled trial. In total, 192 patients scheduled for elective cardiac surgery with cardiopulmonary bypass (CPB) and aortic cross-clamp will be randomized into one of the two treatment arms. In the experimental group, besides conventional lung protective ventilation, sigh volumes producing plateau pressures of 35 cmH2O (or 40 cmH2O for patients with body mass index > 35 kg/m2) delivered once every 6 min from intubation to extubation. In the control group, conventional lung protective ventilation without preplanned recruitment maneuvers is used. Lung protective ventilation (LPV) consists of low tidal volumes (6-8 mL/kg of predicted body weight) and positive end-expiratory pressure (PEEP) setting according to low PEEP/FiO2 table for acute respiratory distress syndrome (ARDS). The primary endpoint is time-weighted average SpO2/FiO2 ratio during the initial post-extubation hour. Main secondary endpoint is the severity of postoperative pulmonary complications (PPCs) computed by postoperative day 7. DISCUSSION: The E-SIGHT trial will be the first randomized controlled trial to evaluate the impact of perioperative sigh ventilation on the postoperative outcomes after on-pump cardiac surgery. The trial will introduce and assess a novel perioperative ventilation approach to mitigate the risk of postoperative hypoxemia and PPCs in patients undergoing cardiac surgery. Also provide the basis for a future larger trial aiming at verifying the impact of sigh ventilation on postoperative pulmonary complications. TRIAL REGISTRATION: ClinicalTrials.gov NCT06248320. Registered on January 30, 2024. Last updated February 26, 2024.

[Changes of lung function and inflammatory factors in rat models of coal workers' pneumoconiosis].

Objective: To observe the changes of lung function and inflammatory factors in rat models of coal workers' pneumoconiosis at different time points. Methods: In June 2021, 96 healthy male SD rats with SPF grade were divided into 1, 3, and 6-month control group and dust staining group (coal dust group, coal silica dust group, quartz group) according to random number table method, with 8 rats in each group. After one week of adaptive feeding, a one-time non-exposed tracheal perfusion method (1 ml/ piece) was used. The dust dyeing group was given 50 g/L coal dust, coal silica mixed dust and quartz dust suspension, respectively, and the control group was given 0.9% normal saline solution. At 1, 3 and 6 months after perfusion, lung function was detected by animal lung function apparatus, then all lung tissues and alveolar lavage fluid were killed, and lung histopathological morphological changes were observed by HE staining, and the contents of interleukin (IL-1ß), IL-18, IL-4 and IL-10 in alveolar lavage fluid were detected by ELISA. One-way analysis of variance was used to compare groups. Two factors (inter-group treatment factor (4 levels) and observation time factor (3 levels) ) were used in the analysis of the effects of inter-group treatment and treatment time on related indicators. Results: HE staining results showed that coal spot appeared in the lung tissue of coal dust group, coal spot and coal silicon nodule appeared in the lung tissue of coal dust group, and silicon nodule appeared in the lung tissue of quartz group. Compared with the control group, the forced vital capacity (FVC) and forced expiratory volume at 0.2 second (FEV(0.2)) of rats in the dust staining group had interaction between the treatment and treatment time (P<0.05). With the increase of dust dyeing time, FVC and FEV(0.2) decreased significantly at 3-6 months of dust dyeing, and the maximum gas volume per minute (MVV) decreased significantly at 1-3 months of dust dyeing (P<0.05). The lowest lung function index was in quartz group, followed by coal-silica group and coal-dust group. There were statistically significant differences in the main effect and interaction effect of the pro-inflammatory factor IL-18 among all groups in treatment and treatment time (IL-18: F=70.79, 45.97, 5.90, P<0.001), and interaction existed. The highest content of inflammatory factors in alveolar lavage fluid of all dust groups was quartz group, followed by coal silica group and coal dust group. There were significant differences in the main effect and interaction effect of anti-inflammatory factors between groups and treatment time (IL-4: F=41.55, 33.01, 5.23, P<0.001, <0.001, <0.001; IL-10: F=7.46, 20.80, 2.91, P=0.002, <0.001, 0.024), and there was interaction. The highest content of anti-inflammatory factor was in quartz group, followed by coal silica group and coal dust group. Conclusion: Lung function decreased and levels of inflammatory fators increased in rat models of coal workers' pneumoconiosis, with the quartz group being the most severely damaged. Lung function is mainly impaired in thrid-six months, and the content of inflammatory factors begins to change in first-thrid months. MVV are the earliest and most obvious in lung function. IL-18 is suitable for monitoring changes in the pro-inflammatory response of coal workers' pneumoconiosis, and IL-10 is suitable for monitoring changes in anti-inflammatory response.

Inspiratory Muscle Training for Lung Transplant Candidates and Recipients.

OBJECTIVES: Inspiratory muscle training is used in rehabilitation to exercise respiratory muscles in various conditions associated with limited ventilatory reserve. In this review, we investigated inspiratory muscle training in lung transplant candidates and recipients. MATERIALS AND METHODS: We searched 5 primary databases from inception through April 2024. Two key word entries, "lung transplantation" and "inspiratory muscle training," were matched using the Boolean operator AND. No filters were applied for document type, age, sex, publication date, language, and subject. RESULTS AND CONCLUSIONS: The searched databases returned 119 citations. Seven articles that considered 64 patients (47% female) were included in the final analysis, with 1 study involving a pediatric patient. Lung transplant recipients used a threshold trainer at 15% to 60% of maximal inspiratory pressure and mostly exercised twice daily for 10 to 15 minutes per session. Lung transplant candidates exercised at 30% to >50% of maximal inspiratory pressure twice daily, performing 30 to 60 inspirations or for 15 minutes. The highest inspiratory muscle strength was observed in a series of adult lung transplant recipients whose mean value improved by 31.8 ± 14.6 cmH2O versus baseline after treatment. To the same extent, the highest value of maximal inspiratory pressure was detected in a pediatric patient who scored 180 cmH2O after training. Overall, participants obtained improvements in lung function (forced expiratory volume in 1 second, forced vital capacity), functional performance, dyspnea intensity, and exercise tolerance. Inspiratory muscle training is easy to perform and can be done at home without specific supervision (in adults) before or after a lung transplant. Nevertheless, additional rigorous investigations should aim to replicate the positive effects reported in the present review.

Identifying limitations to exercise with incremental cardiopulmonary exercise testing: a scoping review.

Cardiopulmonary exercise testing (CPET) is a comprehensive and invaluable assessment used to identify the mechanisms that limit exercise capacity. However, its interpretation remains poorly standardised. This scoping review aims to investigate which limitations to exercise are differentiated by the use of incremental CPET in literature and which criteria are used to identify them. We performed a systematic, electronic literature search of PubMed, Embase, Cochrane CENTRAL, Web of Science and Scopus. All types of publications that reported identification criteria for at least one limitation to exercise based on clinical parameters and CPET variables were eligible for inclusion. 86 publications were included, of which 57 were primary literature and 29 were secondary literature. In general, at the level of the cardiovascular system, a distinction was often made between a normal physiological limitation and a pathological one. Within the respiratory system, ventilatory limitation, commonly identified by a low breathing reserve, and gas exchange limitation, mostly identified by a high minute ventilation/carbon dioxide production slope and/or oxygen desaturation, were often described. Multiple terms were used to describe a limitation in the peripheral muscle, but all variables used to identify this limitation lacked specificity. Deconditioning was a frequently mentioned exercise limiting factor, but there was no consensus on how to identify it through CPET. There is large heterogeneity in the terminology, the classification and the identification criteria of limitations to exercise that are distinguished using incremental CPET. Standardising the interpretation of CPET is essential to establish an objective and consistent framework.

Quantitative CT analysis of idiopathic pulmonary fibrosis and correlation with lung function study.

BACKGROUND: Idiopathic Pulmonary Fibrosis (IPF) is a progressive fibrotic lung disease. However, the field of quantitative CT scan analysis in conjunction with pulmonary function test for IPF patients remains relatively understudied. In this study, we evaluated the diagnostic value of features derived high-resolution computed tomography (HRCT) for patients with IPF and correlated them with pulmonary function tests. METHODS: We retrospectively analyzed the chest HRCT images and pulmonary function test results of 52 patients with IPF during the same period (1 week) and selected 52 healthy individuals, matched for sex, age, and body mass index (BMI) and with normal chest HRCT as controls. HRCT scans were performed using a Philips 256-row Brilliance iCT scanner with standardized parameters. Lung function tests were performed using a Jaeger volumetric tracer for forced vital capacity (FVC), total lung capacity (TLC), forced expiratory volume in first second (FEV1), FEV1/FVC, carbon monoxide diffusing capacity (DLCO), and maximum ventilation volume (MVV) metrics. CT quantitative analysis, including tissue segmentation and threshold-based quantification of lung abnormalities, was performed using 3D-Slicer software to calculate the percentage of normal lung areas (NL%), percentage of ground-glass opacity areas (GGO%), percentage of fibrotic area (F%) and abnormal lesion area percentage (AA%). Semi-quantitative analyses were performed by two experienced radiologists to assess disease progression. The aortic-to-sternal distance (ASD) was measured on axial images as a standardized parameter. Spearman or Pearson correlation analysis and multivariate stepwise linear regression were used to analyze the relationship between the data in each group, and the ROC curve was used to determine the optimal quantitative CT metrics for identifying IPF and controls. RESULTS: ROC curve analysis showed that F% distinguished the IPF patient group from the control group with the largest area under the curve (AUC) of 0.962 (95% confidence interval: 0.85-0.96). Additionally, with F% = 4.05% as the threshold, the Youden's J statistic was 0.827, with a sensitivity of 92.3% and a specificity of 90.4%. The ASD was significantly lower in the late stage of progression than in the early stage (t = 5.691, P < 0.001), with a mean reduction of 2.45% per month. Quantitative CT indices correlated with all pulmonary function parameters except FEV1/FVC, with the highest correlation coefficients observed for F% and TLC%, FEV1%, FVC%, MVV% (r = - 0.571, - 0.520, - 0.521, - 0.555, respectively, all P-values < 0.001), and GGO% was significantly correlated with DLCO% (r = - 0.600, P < 0.001). Multiple stepwise linear regression analysis showed that F% was the best predictor of TLC%, FEV1%, FVC%, and MVV% (R2 = 0.301, 0.301, 0.300, and 0.302, respectively, all P-values < 0.001), and GGO% was the best predictor of DLCO% (R2 = 0.360, P < 0.001). CONCLUSIONS: Quantitative CT analysis can be used to diagnose IPF and assess lung function impairment. A decrease in the ASD may indicate disease progression.

Maximal respiratory pressure after COVID-19 compared with reference material in healthy adults: A prospective cohort study (The SECURe study).

After COVID-19 long term respiratory symptoms and reduced lung function including maximal inspiratory pressure (MIP) and maximal expiratory pressure (MEP) have been reported. However, no studies have looked at MIP and MEP in all disease groups and the reference materials collection methods differ substantially. We aimed to determine MIP and MEP in individuals after COVID-19 infection with different disease severity using reference material of healthy control group obtained using the same standardized method. Patients with COVID-19 were included March 2020-March 2021 at Rigshospitalet, Denmark. MIP and MEP were measured using microRPM. Predicted MIP and MEP were calculated using reference material obtained from 298 healthy adults aged 18-97 years using the same method. In SECURe, 145 participants were measured median 5 months after COVID-19 diagnosis and of these 16% had reduced MIP and/or MEP. There was reduced spirometry and total lung capacity, but not reduced diffusion capacity in those with abnormal MIP and/or MEP compared with normal MIP and MEP. Of those with reduced MIP and/or MEP at 5 months, 80% still had reduced MIP and/or MEP at 12 months follow-up. In conclusion, few have reduced MIP and/or MEP 5 months after COVID-19 and little improvement was seen over time.

The relationship between cardiometabolic index and pulmonary function among U.S. adults: insights from the National Health and Nutrition Examination Survey (2007-2012).

BACKGROUND: Previous findings have revealed that disorders of lipid metabolism may be a risk factor for pulmonary function damage; however, the combined effect of dyslipidemia and central obesity on pulmonary function is unclear. The cardiometabolic index (CMI) is a composite of serum lipids (triglyceride (TG)/high-density lipoprotein cholesterol (HDL-C)) and visceral fat parameters (waist-to-height ratio (WHtR)). This research aimed to investigate the link between CMI and pulmonary function, employing large-scale demographic data sourced from the National Health and Nutrition Examination Survey (NHANES) database. METHODS: This cross-sectional study used data involving 4125 adults aged 20 and above collected by NHANES between 2007 and 2012. We defined CMI as the exposure variable and measured outcomes using forced expiratory volume in one second (FEV1), forced vital capacity (FVC), and FEV1/FVC to evaluate pulmonary function. Weighted multiple linear regression models and subgroup analyses were employed to investigate separate relationships between CMI and pulmonary function. In addition, to investigate variations across different strata and evaluate the robustness of the findings, interaction tests and sensitivity analyses were conducted. RESULTS: Results from the weighted multiple linear regression analysis indicated a unit increase in log2-CMI was associated with a reduction of 82.63 mL in FEV1 and 112.92 mL in FVC. The negative association remained significant after transforming log2-CMI by quartile (Q). When the log2-CMI level reached Q4, ß coefficients (ß) were -128.49 (95% CI: -205.85, -51.13), -169.01 (95% CI: -266.72, -71.30), respectively. According to the interaction test findings, the negative association linking log2-CMI with FEV1 and FVC persists regardless of confounding factors including age, gender, BMI, physical activity (PA), and smoking status. A subsequent sensitivity analysis provided additional confirmation of the stability and reliability of the results. For females, the inflection points for the nonlinear relationships between log2-CMI and FEV1, as well as log2-CMI and FVC, were identified at 2.33 and 2.11, respectively. While in males, a consistent negative association was observed. CONCLUSIONS: Our findings suggest that higher CMI is associated with lower FEV1 and FVC. CMI may serve as a complementary consideration to the assessment and management of pulmonary function in clinical practice.