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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 -
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 -
Archives of Razi Institute Jun 2022This study was performed to evaluate the prognostic value of relative changes from admission to discharge (Δ%) of integrated congestion assessment to predict adverse...
This study was performed to evaluate the prognostic value of relative changes from admission to discharge (Δ%) of integrated congestion assessment to predict adverse outcomes in patients with irreversible heart failure (HF) during a one-year follow-up. The study included 122 patients (60% males, median age of 69 years) with decompensated HF. Most of the patients (92%) had a history of arterial hypertension, 53.3% had coronary heart disease, and 40.2% had type 2 diabetes mellitus. All patients underwent assessments, including NT-proBNP, lung ultrasound (LUS) B-line score, liver stiffness by transient elastography, and resistance and reactance by bioimpedance vector analysis (BIVA). The assessments were performed at admission and discharge, and a relative change from admission (delta percentage, Δ%) was calculated. Long-term clinical outcomes were assessed by a structured interview conducted 1, 3, 6, and 12 months after discharge. The cut-offs for the occurrence of the endpoint events were Δ% NT-proBNP of ≥ -25, Δ% liver stiffness of ≥ -44, Δ% B-line score on lung ultrasound of ≥ -73, Δ% BIVA resistance of ≤ 18, and Δ% BIVA reactance of ≤ 40. It was revealed that 55% of endpoint events, including 22 (18%) deaths and 33 (27%) readmissions, occurred within a median of 74 days (interquartile range: 33-147). Patients with an endpoint event had significantly worse values of all studied parameters in contrast to patients without it. There was a significant direct association between Δ% NT-proBNP and Δ% B-lines (r=0.18; =0.04), and a highly reliable inverse association was observed between Δ% liver stiffness and Δ% BIVA reactance (r=-0.4; <0.001). No significant associations were found between the other parameters. Univariate Cox regression analysis demonstrated the independent prognostic value of all congestion markers under study (NT-proBNP, LUS B-lines, liver stiffness, and BIVA reactance) for predicting the combined endpoint. Multivariate Cox regression analysis confirmed the independent prognostic value in predicting the risk of endpoint event for the following parameters: NT-proBNP (hazard rate [HR] 2.5, =0.001), liver stiffness (HR 2.3, =0.012), LUS B-line score (HR 2.2, =0.008). However, it did not find any significant prognostic value for BIVA resistance and reactance. The relative admission-to-discharge change in the integral assessment of congestion had a prognostic value for predicting the risk of adverse outcomes (all-cause mortality and readmission rate) in patients with decompensated HF during a one-year follow-up.
Topics: Aged; Female; Humans; Male; Diabetes Mellitus, Type 2; Heart Failure; Patient Discharge; Prognosis; Prospective Studies
PubMed: 36618279
DOI: 10.22092/ARI.2022.357393.2033 -
Scientific Reports May 2019Overlap of asthma and COPD has attracted attention recently. We aimed to clarify physiological and morphological differences of the airways between COPD and asthma-COPD... (Comparative Study)
Comparative Study Observational Study
Overlap of asthma and COPD has attracted attention recently. We aimed to clarify physiological and morphological differences of the airways between COPD and asthma-COPD overlap (ACO). Respiratory resistance and reactance and three-dimensional computed tomography data were evaluated in 167 patients with COPD. Among them, 43 patients who fulfilled the diagnosis of asthma were defined as having ACO. Among 124 patients with COPD without ACO, 86 with a comparable smoking history and airflow limitation as those with ACO were selected using propensity score matching (matched COPD). The intraluminal area (Ai) and wall thickness (WT) of third- to sixth-generation bronchi were measured and adjusted by body surface area (BSA; Ai/BSA and WT/√BSA, respectively). Patients with ACO had higher respiratory resistance and reactance during tidal breathing, but a smaller gap between the inspiratory and expiratory phases, compared with matched patients with COPD. Patients with ACO had a greater WT/√BSA in third- to fourth-generation bronchi, smaller Ai/BSA in fifth- to sixth-generation bronchi, and less emphysematous changes than did matched patients with COPD. Even when patients with ACO and those with COPD have a comparable smoking history and fixed airflow limitation, they have different physiological and morphological features of the airways.
Topics: Aged; Airway Resistance; Asthma-Chronic Obstructive Pulmonary Disease Overlap Syndrome; Bronchi; Female; Humans; Imaging, Three-Dimensional; Male; Middle Aged; Prospective Studies; Pulmonary Disease, Chronic Obstructive; Spirometry; Tomography, X-Ray Computed
PubMed: 31127165
DOI: 10.1038/s41598-019-44345-6 -
ERJ Open Research Oct 2020Although the utility of oscillometry for predicting disease severity in idiopathic pulmonary fibrosis (IPF) had been researched, little has been reported on the...
Although the utility of oscillometry for predicting disease severity in idiopathic pulmonary fibrosis (IPF) had been researched, little has been reported on the mechanism of why respiratory impedance reflects disease severity. In addition, traction bronchiectasis has been considered to reduce respiratory resistance and correlate negatively with airflow obstruction, but this hypothesis has not been validated. The present study aimed to investigate the correlations between oscillometric parameters and fibrosis-related lung abnormalities in IPF and to assess the utility of oscillometry as a surrogate marker for traction bronchiectasis and airflow obstruction. Eighty Japanese patients with IPF underwent high-resolution computed tomography (HRCT), spirometry, and oscillometry and were retrospectively investigated. Fibrosis-related HRCT findings were scored regarding airspace consolidation, honeycombing, architectural distortion, traction bronchiectasis, and fibrosis. Correlations between the HRCT scores, spirometric parameters, and oscillometric parameters were analysed. Respiratory reactance correlated positively with all fibrosis-related HRCT scores. Vital capacity and forced vital capacity (FVC) correlated negatively with oscillometric parameters and HRCT scores, reflecting the severity of restrictive ventilatory deficiency. Respiratory resistance was not related to any of the HRCT scores or forced expiratory volume in 1 s/FVC. However, forced expiratory volume in 1 s/FVC correlated positively with HRCT scores, which showed that airflow obstruction became milder as the disease progressed. In conclusion, respiratory reactance reflects fibrosis and restrictive ventilatory deficiency in IPF. Moreover, respiratory resistance is independent of traction bronchiectasis and airflow obstruction in patients with IPF, which implies that respiratory resistance might reflect different properties of the airways.
PubMed: 33344627
DOI: 10.1183/23120541.00391-2020 -
Environmental Research Oct 2023Poly- and perfluoroalkyl substances (PFAS) are used in a wide range of products. Experimental studies suggested impaired lung development and pro-inflammatory response...
BACKGROUND
Poly- and perfluoroalkyl substances (PFAS) are used in a wide range of products. Experimental studies suggested impaired lung development and pro-inflammatory response following exposure to some PFAS. We aimed to assess the associations between prenatal exposure to PFAS and children respiratory health.
METHODS
The study is based on 433 mother-child pairs. 26 PFAS were measured in maternal serum collected during pregnancy. Lung function parameters were measured at 2 months using tidal breathing flow-volume loops and multiple-breath nitrogen washout and at 36 months using oscillometry. Incidence of respiratory health diseases (asthma, wheeze, bronchitis, bronchiolitis) in the first 36 months of life was assessed by repeated questionnaires. A cluster-based analysis was applied to identify prenatal PFAS exposure patterns. Adjusted linear and logistic regressions were performed to assess the associations between PFAS exposure patterns as well as individual PFAS, and each respiratory health parameter.
RESULTS
We excluded 13 PFAS due to low quantification (<5%). Relying on the 13 remaining PFAS, we identified three exposure clusters, characterized by low (N = 163), medium (N = 236) and high (N = 51) pregnancy PFAS concentrations. Compared to children belonging to the low exposure group, children in the moderate exposure group had higher reactance at 7 Hz (X) and lower frequency dependence of resistance between 7 Hz and 19 Hz (R) at 36 months, suggesting better lung function. No association of any exposure metric was detected with respiratory diseases in the first 3 years of life.
CONCLUSIONS
Our study relying on both mixture and uni-pollutant analyses, does not provide evidence for a deleterious effect of prenatal PFAS exposure on respiratory health at an early age.
Topics: Pregnancy; Female; Humans; Prenatal Exposure Delayed Effects; Fluorocarbons; Environmental Pollutants; Asthma; Incidence; Alkanesulfonic Acids
PubMed: 37406719
DOI: 10.1016/j.envres.2023.116544 -
The European Respiratory Journal Sep 2020Telemonitoring trials for early detection of acute exacerbations of chronic obstructive pulmonary disease (AECOPD) have provided mixed results. Day-to-day variations in...
BACKGROUND
Telemonitoring trials for early detection of acute exacerbations of chronic obstructive pulmonary disease (AECOPD) have provided mixed results. Day-to-day variations in lung function measured by the forced oscillation technique (FOT) may yield greater insight. We evaluated the clinical utility of home telemonitoring of variability in FOT measures in terms of 1) the relationship with symptoms and quality of life (QoL); and 2) the timing of variability of FOT measures and symptom changes prior to AECOPD.
METHODS
Daily FOT parameters at 5 Hz (resistance (R) and reactance (X); Resmon Pro Diary, Restech Srl, Milan, Italy), daily symptoms (COPD Assessment Test (CAT)) and 4-weekly QoL data (St George's Respiratory Questionnaire (SGRQ)) were recorded over 8-9 months from chronic obstructive pulmonary disease (COPD) patients. Variability of R and X was calculated as the standard deviation (sd) over 7-day running windows and we also examined the effect of varying window size. The relationship of FOT CAT and SGRQ was assessed using linear mixed modelling, daily changes in FOT variability and CAT prior to AECOPD using one-way repeated measures ANOVA.
RESULTS
Fifteen participants with a mean±sd age of 69±10 years and a % predicted forced expiratory volume in 1 s (FEV) of 39±10% had a median (interquartile range (IQR)) adherence of 95.4% (79.0-98.8%). Variability of the inspiratory component of X (indicated by the standard deviation of inspiratory reactance (SDX)) related to CAT and weakly to SGRQ (fixed effect estimates 1.57, 95% CI 0.65-2.49 (p=0.001) and 4.41, 95% CI -0.06 to 8.89 (p=0.05), respectively). SDX changed significantly on the same day as CAT (1 day before AECOPD, both p=0.02) and earlier when using shorter running windows (3 days before AECOPD, p=0.01; accuracy=0.72 for 5-day windows).
CONCLUSIONS
SDX from FOT telemonitoring reflects COPD symptoms and may be a sensitive biomarker for early detection of AECOPD.
Topics: Forced Expiratory Volume; Humans; Italy; Pulmonary Disease, Chronic Obstructive; Quality of Life; Respiratory Function Tests
PubMed: 32430416
DOI: 10.1183/13993003.01739-2019 -
BMJ Open Respiratory Research Apr 2022Markers of idiopathic pulmonary fibrosis (IPF) severity are based on measurements of forced vital capacity (FVC), diffusing capacity (DLCO) and CT. The pulmonary vessel...
BACKGROUND
Markers of idiopathic pulmonary fibrosis (IPF) severity are based on measurements of forced vital capacity (FVC), diffusing capacity (DLCO) and CT. The pulmonary vessel volume (PVV) is a novel quantitative and independent prognostic structural indicator derived from automated CT analysis. The current prospective cross-sectional study investigated whether respiratory oscillometry provides complementary data to pulmonary function tests (PFTs) and is correlated with PVV.
METHODS
From September 2019 to March 2020, we enrolled 89 patients with IPF diagnosed according to international guidelines. We performed standard spectral (5-37 Hz) and novel intrabreath tracking (10 Hz) oscillometry followed by PFTs. Patients were characterised with the gender-age-physiology (GAP) score. CT images within 6 months of oscillometry were analysed in a subgroup (26 patients) using automated lung texture analysis. Correlations between PFTs, oscillometry and imaging variables were investigated using different regression models.
FINDINGS
The cohort (29F/60M; age=71.7±7.8 years) had mild IPF (%FVC=70±17, %DLCO=62±17). Spectral oscillometry revealed normal respiratory resistance, low reactance, especially during inspiration at 5 Hz (X5in), elevated reactance area and resonance frequency. Intrabreath oscillometry identified markedly low reactance at end-inspiration (XeI). XeI and X5in strongly correlated with FVC (r=0.499 and 0.435) while XeI was highly (p=0.004) and uniquely correlated with the GAP score. XeI and PVV exhibited the strongest structural-functional relationship (r=0.690), which remained significant after adjusting for %FVC, %DLCO and GAP score.
INTERPRETATION
XeI is an independent marker of IPF severity that offers additional information to standard PFTs. The data provide a cogent rationale for adding oscillometry in IPF assessment.
Topics: Aged; Cross-Sectional Studies; Humans; Idiopathic Pulmonary Fibrosis; Middle Aged; Oscillometry; Respiratory Function Tests; Tomography, X-Ray Computed
PubMed: 35396320
DOI: 10.1136/bmjresp-2021-001163 -
Impulse oscillometry reference values and correlation with predictors in Turkish preschool children.The Turkish Journal of Pediatrics 2019Er İ, Günlemez A, Baydemir C, Kılıçbay F, Ersu R, Uyan ZS. Impulse oscillometry reference values and correlation with predictors in Turkish preschool children. Turk...
Er İ, Günlemez A, Baydemir C, Kılıçbay F, Ersu R, Uyan ZS. Impulse oscillometry reference values and correlation with predictors in Turkish preschool children. Turk J Pediatr 2019; 61: 560-567. Impulse oscillometry (IOS) is a noninvasive, rapid technique requiring passive cooperation that allows for evaluation of lung function through the measurement of airway resistance and reactance. There are no available reference values for Turkish children. This study is aimed to determine the reference values of IOS parameters and to study their correlation with height, weight, body mass index, and age as predictors in healthy Turkish preschool children. Healthy children between 3-7 years of age who were selected according to ERS/ATS criteria and followed at Kocaeli University outpatient clinic performed IOS. The correlation between the anthropometric predictor variables and resistance and reactance at 5-20 hertz (R5-R20 and X5-X20), the respiratory impedance at 5 hertz (Z5), resistance area (AX) and resonance frequency (Fres) were assessed by regression analysis and stepwise method. 151 children (93 female) with the mean age of 67.9±16.2 months participated in the study. Multilinear regression analysis for IOS values of all children revealed that resistance was significantly correlated with height and reactance was significantly correlated with age (p < 0.05). For girls, height had a negative effect on R5-20, Z5, AX values, while age had a positive effect on X5-20 and a negative effect on Fres (p < 0.05). For boys, weight had a negative effect on R5- 20, Z5 values, while age had a positive effect on X15-20 and a negative effect on AX, Fres (p < 0,05). This study provided reference values of IOS in healthy Turkish children that would be a useful guide for diagnosing and following respiratory diseases in preschool children.
Topics: Anthropometry; Child; Child, Preschool; Electric Impedance; Female; Forced Expiratory Volume; Humans; Lung; Lung Diseases; Male; Oscillometry; Predictive Value of Tests; Reference Values; Respiratory Function Tests; Turkey
PubMed: 31990474
DOI: 10.24953/turkjped.2019.04.013 -
Lung Aug 2019The forced oscillation technique (FOT) measures respiratory impedance during normal tidal breathing and requires minimal patient cooperation. (Comparative Study)
Comparative Study
BACKGROUND
The forced oscillation technique (FOT) measures respiratory impedance during normal tidal breathing and requires minimal patient cooperation.
OBJECTIVE
To compare IOS and AOS devices in patients with asthma and COPD.
METHODS
We compared two different FOT devices, namely impulse oscillometry using a loudspeaker (IOS: Jaeger Masterscreen) and airwave oscillometry using a vibrating mesh (AOS: Thorasys Tremoflo) for pre- and post-bronchodilator measurements in 84 patients with asthma and COPD.
RESULTS
The overall pattern of measurement bias was for higher resistance with IOS and higher reactance with AOS, this being the case in asthma and COPD separately. There were small but significantly higher values using IOS for resistance at 5 Hz (R5) and 20(19) Hz (R20(19)). In converse, values for reactance at 5 Hz (X5), reactance area (AX) and resonant frequency (Fres) were significantly higher using AOS but to a much larger extent. The difference in AX between devices was more pronounced in COPD than in asthma. Salbutamol reversibility as % change was greater in asthma than COPD patients with AX but not FEV1.
CONCLUSION
Our study showed evidence of better agreement for resistance than reactance when comparing IOS and AOS, perhaps inferring that AOS may be more sensitive at measuring reactance in patients with airflow obstruction.
Topics: Aged; Airway Resistance; Albuterol; Asthma; Bronchodilator Agents; Equipment Design; Female; Forced Expiratory Volume; Humans; Lung; Male; Maximal Midexpiratory Flow Rate; Middle Aged; Oscillometry; Predictive Value of Tests; Pulmonary Disease, Chronic Obstructive; Reproducibility of Results; Respiratory Function Tests; Retrospective Studies; Vital Capacity
PubMed: 31273438
DOI: 10.1007/s00408-019-00247-y