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Rhinology Jun 2023Although lower airway hyperresponsiveness is present in approximately one in three patients with allergic rhinitis (AR), the underlying mechanism remains unclear. To...
BACKGROUND
Although lower airway hyperresponsiveness is present in approximately one in three patients with allergic rhinitis (AR), the underlying mechanism remains unclear. To evaluate nasal patency and pulmonary functions in AR independently of the presence of asthma and to investigate the relationships between these and nasal oxidative stress parameters and endothelial damage.
METHODOLOGY
Seventy adolescents with AR (AR group - 27 with asthma and 43 without asthma) and 30 healthy controls (HC group) were included in this prospective, cross-sectional study. Endocan and oxidative biomarkers [total oxidant status (TOS), total antioxidant status (TAS), and oxidative stress index (OSI)] in nasal lavage fluid specimens; peak nasal inspiratory flow (PNIF); fractional exhaled nitric oxide (FeNO), and impulse oscillometry (zR5, zR20, and R5-20 for resistance and zX5 and zX20 for reactance) were investigated.
RESULTS
Nasal endocan, TOS, and OSI values were higher in the AR group and TAS in the HC group. There was no difference between AR groups with and without asthma in terms of nasal endocan and oxidative biomarkers. FeNO levels and airway resistance (zR5, zR20, and R5-20) were higher in the AR group than in the HC group. However, there was no difference between the groups in PNIF. X5 was higher among the AR without asthma than in the other groups. Correlation between OSI and R5-20 was observed in the AR group. In the linear regression model, (logged) OSI was significantly predicted (logged) R5-20.
CONCLUSIONS
The airways of adolescents with AR without asthma were as much affected as those of the AR with asthma, and this effect was associated with nasal endothelial damage and an increase in oxidative stress.
Topics: Adolescent; Humans; Rhinitis, Allergic, Perennial; Prospective Studies; Cross-Sectional Studies; Rhinitis, Allergic; Asthma; Nitric Oxide; Oxidative Stress
PubMed: 36946425
DOI: 10.4193/Rhin22.484 -
The European Respiratory Journal Aug 2021
Topics: Aged; Airway Obstruction; Asthma; Forced Expiratory Volume; Humans; Lung; Non-Smokers; Pulmonary Disease, Chronic Obstructive
PubMed: 33863745
DOI: 10.1183/13993003.04400-2020 -
Therapeutic Advances in Respiratory... 2023A few studies have reported the medium-sized and small airway morphological abnormalities of bronchiolitis. Whether spirometry or impulse oscillometry (IOS) is...
BACKGROUND
A few studies have reported the medium-sized and small airway morphological abnormalities of bronchiolitis. Whether spirometry or impulse oscillometry (IOS) is correlated with airway remodeling of bronchiolitis remains unclear.
OBJECTIVES
Aiming to demonstrate the airway morphological abnormalities of bronchiolitis obliterans (BO) and diffuse panbronchiolitis (DPB) assessed by endobronchial optical coherence tomography (EB-OCT), and elucidate whether spirometric and IOS parameters have correlation with the airway remodeling of bronchiolitis.
METHODS
We recruited 18 patients with bronchiolitis (BO, = 9; DPB, = 9) and 17 control subjects. Assessments of clinical features, St. George's respiratory questionnaire (SGRQ), chest computed tomography (CT), spirometry, IOS, and EB-OCT were performed in all enrolled subjects. The correlation between EB-OCT and lung function parameters was studied and analyzed.
RESULTS
The magnitude of abnormalities of spirometric and IOS parameters was significantly greater in patients with bronchiolitis than that in control subjects ( < 0.05). Patients with BO had notably lower forced expiratory volume in 1 s (FEV), forced vital capacity (FVC), FEV/FVC, maximal mid-expiratory flow (MMEF)% pred and higher resonant frequency (Fres), and area of reactance (AX) than those with DPB ( < 0.05). The EB-OCT measurement among patients with bronchiolitis and between the bronchus in the left and the right lung demonstrated a heterogeneous distribution of airway calibers, presenting a high intra- and inter-individual variability. Patients with bronchiolitis had notably greater airway wall area ( < 0.05) compared with control, while BO presented greater magnitude of airway abnormalities than DPB. Fres and the difference in airway resistance at 5 and 20 Hz (R-R) correlated negatively with medium-sized and small airway inner area, and correlated positively with airway wall area ( < 0.05), whose correlation coefficients were higher than those of spirometric parameters.
CONCLUSION
Bronchiolitis, BO and DPB, manifested a heterogeneous distribution of airway calibers with significant intra- and inter-individual variability. IOS parameters, rather than spirometry, correlated better with medium-sized and small airway remodeling in bronchiolitis assessed by EB-OCT measurement.
Topics: Humans; Tomography, Optical Coherence; Airway Remodeling; Lung; Respiratory Function Tests; Spirometry; Forced Expiratory Volume; Bronchiolitis
PubMed: 37073792
DOI: 10.1177/17534666231167351 -
The Journal of Allergy and Clinical... May 2022Asthma is defined by the presence of reversible airflow limitation, yet persistently abnormal spirometry may develop despite appropriate asthma treatment. Fixed airflow...
BACKGROUND
Asthma is defined by the presence of reversible airflow limitation, yet persistently abnormal spirometry may develop despite appropriate asthma treatment. Fixed airflow obstruction (FAO) describes abnormal postbronchodilator spirometry that is associated with greater symptom burden and disease severity. Respiratory oscillometry measures the mechanics of the entire airway tree, including peripheral airway changes that have been shown to influence asthma symptoms.
OBJECTIVE
To evaluate the relationship between abnormal oscillometry following bronchodilator and symptom control in adults with asthma.
METHODS
A prospective cohort of patients with asthma attending an airways clinic completed oscillometry (resistance and reactance), spirometry, and the Asthma Control Test. Postbronchodilator lung function below the lower limit of normal was considered abnormal. Spirometric FAO was defined as FEV/forced vital capacity below the lower limit of normal. Spearman's rank coefficient and multiple linear regression were performed to assess associations of lung function parameters with Asthma Control Test. The discriminative ability of abnormal lung function to identify poor asthma control was determined using Cohen's kappa.
RESULTS
Ninety patients with asthma were included; 48% had spirometric FAO. Only reactance parameters, not spirometry, significantly related to (r ≥ 0.315; P < .05) and identified asthma control (r = 0.236; P < .001). Lung function was more strongly associated with asthma control in patients with FAO compared with those without. Abnormal oscillometry identified an additional 24% of patients with poor asthma control as compared with spirometric FAO.
CONCLUSIONS
Reactance related to asthma control, independently of spirometric FAO. Abnormal postbronchodilator reactance identified more patients with poor asthma control compared with spirometry. These findings confirm that oscillometry is a relevant lung function test in the clinical assessment of asthma.
Topics: Adult; Asthma; Forced Expiratory Volume; Humans; Lung; Oscillometry; Prospective Studies; Pulmonary Disease, Chronic Obstructive; Spirometry
PubMed: 34979333
DOI: 10.1016/j.jaip.2021.12.026 -
Comparative evaluation of expiratory airflow limitation between patients with COPD and BE using IOS.Scientific Reports Feb 2021Impulse oscillometry (IOS) allows evaluation of the compartmentalized resistance and reactance of the respiratory system, distinguishing central and peripheral... (Comparative Study)
Comparative Study
Impulse oscillometry (IOS) allows evaluation of the compartmentalized resistance and reactance of the respiratory system, distinguishing central and peripheral obstruction. The IOS measurements are getting attention in the diagnosis and differentiation of chronic respiratory diseases. However, no data are available in the literature to differentiate between COPD and BE using IOS parameters. We aimed to evaluate the feasibility of IOS in the diagnosis of bronchiectasis non-cystic fibrosis (BE) in comparison to COPD. Whole breath, inspiration, expiration, and inspiratory-expiratory difference (Δ) were evaluated based on the IOS parameters: total resistance (R5), central airway resistance (R20), peripheral airway resistance (R5-R20), reactance (X5), reactance area (AX), and resonance frequency (Fres). Fifty-nine subjects (21 Healthy, 19 BE, and 19 COPD) participated in this study. It was observed a significant difference in the comparison of healthy and pulmonary disease groups (BE and COPD) for total breathing (R5-R20, X5, AX, and Fres), inspiratory phase (R5 and R5-R5), and expiratory phase (R5-R20 and X5). The comparison between BE and COPD groups showed significant difference in the expiratory phase for resistance at 5 and 20 Hz and, ΔR5 and ΔR20. The IOS evidenced an increase of R5, R20 and R5-R20 in patients with BE and COPD when compared to healthy subjects. Expiratory measures of IOS revealed increased airway resistance in COPD compared to BE patients who had similar FEV1 measured by spirometry, however, further studies are needed to confirm these differences.
Topics: Aged; Airway Resistance; Bronchiectasis; Case-Control Studies; Disease Management; Female; Forced Expiratory Volume; Humans; Male; Middle Aged; Oscillometry; Pulmonary Disease, Chronic Obstructive; Pulmonary Ventilation; Respiratory Function Tests; Spirometry
PubMed: 33633234
DOI: 10.1038/s41598-021-84028-9 -
Frontiers in Physiology 2022Chronic lung allograft dysfunction (CLAD) is the major cause of death beyond 2 years after lung transplantation and develops in 50% of all patients by 5 years...
Chronic lung allograft dysfunction (CLAD) is the major cause of death beyond 2 years after lung transplantation and develops in 50% of all patients by 5 years post-transplant. CLAD is diagnosed on the basis of a sustained drop of 20% for at least 3 months in the forced expiratory volume (FEV), compared to the best baseline value achieved post-transplant. CLAD presents as two main phenotypes: bronchiolitis obliterans syndrome (BOS) is more common and has better prognosis than restrictive allograft syndrome (RAS). Respiratory oscillometry is a different modality of lung function testing that is highly sensitive to lung mechanics. The current study investigated whether spectral and intrabreath oscillometry can differentiate between CLAD-free, BOS- and RAS-CLAD at CLAD onset, i.e., at the time of the initial 20% drop in the FEV. A retrospective, cross-sectional analysis of 263 double lung transplant recipients who underwent paired testing with oscillometry and spirometry at the Toronto General Pulmonary Function Laboratory from 2017 to 2022 was conducted. All pulmonary function testing and CLAD diagnostics were performed following international guidelines. Statistical analysis was conducted using multiple comparisons. The RAS ( = 6) spectral oscillometry pattern differs from CLAD-free ( = 225) by right-ward shift of reactance curve similar to idiopathic pulmonary fibrosis whereas BOS ( = 32) has a pattern similar to obstructive lung disease. Significant differences were found in most spectral and intrabreath parameters between BOS, RAS, and time-matched CLAD-free patients. analysis revealed these differences were primarily driven by BOS instead of RAS. While no differences were found between CLAD-free and RAS patients with regards to spectral oscillometry, the intrabreath metric of reactance at end-inspiration (XeI) was significantly different ( < 0.05). BOS and RAS were differentiated by spectral oscillometry measure R5, and intrabreath resistance at end expiration, ReE ( < 0.05 for both). Both spectral and intrabreath oscillometry can differentiate BOS-CLAD from CLAD-free states while intrabreath oscillometry, specifically XeI, can uniquely distinguish RAS-CLAD from CLAD-free. Spectral and intrabreath oscillometry offer complementary information regarding lung mechanics in CLAD patients to help distinguish the two phenotypes and could prove useful in prognostication.
PubMed: 36277208
DOI: 10.3389/fphys.2022.980942 -
Revista Da Associacao Medica Brasileira... 2023This study aimed to investigate if there is any correlation between the quantitative computed tomography and the impulse oscillometry or spirometry results of...
OBJECTIVE
This study aimed to investigate if there is any correlation between the quantitative computed tomography and the impulse oscillometry or spirometry results of post-COVID-19 patients.
METHODS
The study comprised 47 post-COVID-19 patients who had spirometry, impulse oscillometry, and high-resolution computed tomography examinations at the same time. The study group consisted of 33 patients with quantitative computed tomography involvement, while the control group included 14 patients who did not have CT findings. The quantitative computed tomography technology was used to calculate percentages of density range volumes. The relationship between percentages of density range volumes for different quantitative computed tomography density ranges and impulse oscillometry-spirometry findings was statistically analyzed.
RESULTS
In quantitative computed tomography, the percentage of relatively high-density lung parenchyma, including fibrotic areas, was 1.76±0.43 and 5.65±3.73 in the control and study groups, respectively. The percentages of primarily ground-glass parenchyma areas were found to be 7.60±2.86 and 29.25±16.50 in the control and study groups, respectively. In the correlation analysis, the forced vital capacity% predicted in the study group was correlated with DRV%[(-750)-(-500)] (volume of the lung parenchyma that has density between (-750)-(-500) Hounsfield units), but no correlation with DRV%[(-500)-0] was detected. Also, reactance area and resonant frequency were correlated with DRV%[(-750)-(-500)], while X5 was correlated with both DRV%[(-500)-0] and DRV%[(-750)-(-500)] density. Modified Medical Research Council score was correlated with predicted percentages of forced vital capacity and X5.
CONCLUSION
After COVID-19, forced vital capacity, reactance area, resonant frequency, and X5 correlated with the percentages of density range volumes of ground-glass opacity areas in the quantitative computed tomography. X5 was the only parameter correlated with density ranges consistent with both ground-glass opacity and fibrosis. Furthermore, the percentages of forced vital capacity and X5 were shown to be associated with the perception of dyspnea.
Topics: Humans; Oscillometry; COVID-19; Spirometry; Thorax; Tomography, X-Ray Computed
PubMed: 37222321
DOI: 10.1590/1806-9282.20221427 -
European Archives of... Jan 2023To assess pulmonary impedance [resistance (zR5, zR20, R5-20, Fres, and AX) and reactance (zX5 and zX20)] using impulse oscillometry (IOS) in children with adenoid...
PURPOSE
To assess pulmonary impedance [resistance (zR5, zR20, R5-20, Fres, and AX) and reactance (zX5 and zX20)] using impulse oscillometry (IOS) in children with adenoid hypertrophy (AH) and its association with the degree of AH, and to evaluate subsequent changes in pulmonary function 3 months after adenoidectomy.
METHODS
This prospective cross-sectional study was conducted with 170 preschool-age children [110 with AH and 60 sex- and age-matched healthy controls (HCs)]. Pulmonary function was analyzed using IOS at baseline (1st visit) in all participants and 3 months after adenoidectomy (2nd visit) in patients who underwent the operation.
RESULTS
The IOS parameters of zR5, zR20, R5-20, Fres, and AX were higher, but zX20 was lower, in children with AH compared to the HCs (p < 0.05 for all). The parameters of zR5, Fres, and AX were higher in children with grade IV AH than in those with grade I (p < 0.001). zR5, zR20, R5-20, Fres, and AX decreased, but zX20 increased, after adenoidectomy (2nd visit) compared to baseline (1st visit) (p < 0.05). Post-adenoidectomy (2nd visit) zR5, AX, Fres values were higher in children with AH compared to baseline values in the HCs (1st visit) (p < 0.05). The area under the ROC curve (AUC) value for estimating adenoidectomy was 0.741 for zX20 (CI 0.648-0.834, p < 0.001) with a cut-off value of ≤ -3.21, sensitivity of 68.8%, and specificity of 70%.
CONCLUSION
This study shows that IOS is a useful method for demonstrating subclinical bronchial obstruction in preschool-age children with AH with greater pulmonary impedance (resistance and reactance). Pulmonary impedance decreased 3 months after adenoidectomy, but remained higher than in the HCs. The IOS parameter of X20 may be predictive of adenoidectomy. This study evaluated the pulmonary functions of children with adenoid hypertrophy (AH) using impulse oscillometry (IOS) and the association with the scale of AH. Pulmonary functions were analyzed using IOS. The main IOS parameters include resistances (zR5 and zR20), reactance (zX5 and zX20), R5-20 (resistance at 5 Hz minus resistance at 20 Hz), resonant frequency (Fres), and AX. Fres is the point at which reactance is zero and is measured in Hz (1/s). The Reactance Area (AX - "Goldman Triangle") represents the integrated low-frequency respiratory reactance magnitude between 5 Hz and Fres. Faster frequencies of R (~ 20 Hz) reflect larger airways, regarded as resistance around the central airways. Lower frequencies of R (~ 5 Hz) providing information around the entire (small and large) airways. Peripheral (small) airway resistance is defined by R5-20. IOS parameters of zR5, zX20, Fres, and AX differed among AH grades I-IV and compared to the HCs (p < 0.001 for all).
Topics: Humans; Child; Child, Preschool; Adenoids; Oscillometry; Cross-Sectional Studies; Prospective Studies; Lung; Spirometry
PubMed: 35907002
DOI: 10.1007/s00405-022-07521-5 -
Respirology (Carlton, Vic.) Jun 2021Asthma guidelines emphasize the importance of assessing lung function and symptoms. The forced oscillation technique (FOT) and its longitudinal relationship with...
BACKGROUND AND OBJECTIVE
Asthma guidelines emphasize the importance of assessing lung function and symptoms. The forced oscillation technique (FOT) and its longitudinal relationship with spirometry and symptoms are unresolved. We examined concordance between longitudinal spirometry, FOT and symptom control, and determined FOT limits of agreement in stable asthma.
METHODS
Over a 3-year period, adults with asthma attending a tertiary clinic completed the asthma control test (ACT), fraction of exhaled nitric oxide (FeNO), FOT and spirometry. Analysis included between-visit concordance for significant change using Cohen's kappa (κ) and stable asthma FOT limits of agreement.
RESULTS
Data (n = 186) from 855 visits (mean ± SD 4.6 ± 3.0 visits), 114 ± 95 days apart, were analysed. Between-visit concordance was moderate between reactance at 5 Hz (X5) and forced expiratory volume in 1 s (FEV ) (κ = 0.34, p = 0.001), and weak between ACT and FEV (κ = 0.18, p = 0.001). Change in FeNO did not correlate with lung function or ACT (κ < 0.05, p > 0.1). Stable asthma between visits (n = 75; 132 visits) had reduced lung function variability, but comparable concordance to the entire cohort. Limits of agreement for FEV (0.42 L), resistance at 5 Hz (2.06 cm H O s L ) and X5 (2.75 cm H O s L ) in stable asthma were at least twofold greater than published values in health.
CONCLUSION
In adults with asthma, there is moderate concordance between longitudinal change in FOT and spirometry. Both tests relate poorly to changes in asthma control, highlighting the need for multi-modal assessment in asthma rather than symptoms alone. The derivation of longitudinal FOT limits of agreement will assist in its clinical interpretation.
Topics: Adult; Asthma; Forced Expiratory Volume; Humans; Oscillometry; Respiratory Function Tests; Spirometry
PubMed: 33797141
DOI: 10.1111/resp.14053 -
Journal of Clinical Medicine Aug 2023Magnetic resonance imaging (MRI) of the chest is becoming more available in the detection and monitoring of early changes in lung function and structure in patients with...
Magnetic resonance imaging (MRI) of the chest is becoming more available in the detection and monitoring of early changes in lung function and structure in patients with cystic fibrosis (CF). The aim of this study was to assess the relationship between pulmonary function tests (PFT) and perfusion deficits in CF children measured by MRI. We performed a retrospective analysis of the perfusion lung MRI scans and the results of spirometry, oscillometry, body plethysmography, single-breath carbon monoxide uptake, and multiple-breath washout technique (MBW). There were statistically significant correlations between the MRI perfusion scores and MBW parameters (2.5% LCI, M1/M0, M2/M0), spirometry parameters (FEV, FVC, FEF25/75), reactance indices in impulse oscillometry (X5Hz, X10Hz), total lung capacity (TLC) measured in single breath carbon monoxide uptake, markers of air-trapping in body plethysmography (RV, RV/TLC), and the diffusing capacity of the lungs for carbon monoxide. We also observed significant differences in the aforementioned PFT variables between the patient groups divided based on perfusion scores. We noted a correlation between markers of functional lung deficits measured by the MRI and PFTs in CF children. MRI perfusion abnormalities were reflected sooner in the course of the disease than PFT abnormalities.
PubMed: 37568538
DOI: 10.3390/jcm12155136