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Lundblad LKA, Robichaud A. Oscillometry of the respiratory system: a translational opportunity not to be missed. Am J Physiol Lung Cell Mol Physiol 2021; 320:L1038-L1056. [PMID: 33822645 PMCID: PMC8203417 DOI: 10.1152/ajplung.00222.2020] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Airway oscillometry has become the de facto standard for quality assessment of lung physiology in laboratory animals and has demonstrated its usefulness in understanding diseases of small airways. Nowadays, it is seeing extensive use in daily clinical practice and research; however, a question that remains unanswered is how well physiological findings in animals and humans correlate? Methodological and device differences are obvious between animal and human studies. However, all devices deliver an oscillated airflow test signal and output respiratory impedance. In addition, despite analysis differences, there are ways to interpret animal and human oscillometry data to allow suitable comparisons. The potential with oscillometry is its ability to reveal universal features of the respiratory system across species, making translational extrapolation likely to be predictive. This means that oscillometry can thus help determine if an animal model displays the same physiological characteristics as the human disease. Perhaps more importantly, it can also be useful to determine whether an intervention is effective as well as to understand if it affects the desired region of the respiratory system, e.g., the periphery of the lung. Finally, findings in humans can also inform preclinical scientists and give indications as to what type of physiological changes should be observed in animal models to make them relevant as models of human disease. The present article will attempt to demonstrate the potential of oscillometry in respiratory research, an area where the development of novel therapies is plagued with a failure rate higher than in other disease areas.
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Affiliation(s)
- Lennart K A Lundblad
- Meakins-Christie Laboratories, McGill University, Montreal, Quebec, Canada.,THORASYS Thoracic Medical Systems Inc., Montreal, Quebec, Canada
| | - Annette Robichaud
- SCIREQ Scientific Respiratory Equipment Inc., Montreal, Quebec, Canada
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Park JH, Lee JH, Kim HJ, Jeong N, Jang HJ, Kim HK, Park CS. Usefulness of impulse oscillometry for the assessment of bronchodilator response in elderly patients with chronic obstructive airway disease. J Thorac Dis 2019; 11:1485-1494. [PMID: 31179091 PMCID: PMC6531754 DOI: 10.21037/jtd.2019.03.34] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND Impulse oscillometry (IOS) is a noninvasive and convenient technique to measure both airway resistance and reactance. This study aimed to evaluate whether IOS can be used to measure bronchodilator response (BDR) in elderly patients with asthma and chronic obstructive pulmonary disease (COPD) and also describe the difference between asthma and COPD. METHODS Seventy patients (30 and 40 with asthma and COPD, respectively) over 65 years of age were enrolled. IOS and spirometry measurements were obtained before and after bronchodilator administration. Correlation analysis was used to compare the percentage changes in spirometry and IOS parameters after bronchodilator administration between the asthma and COPD groups. RESULTS The changes in IOS parameters after bronchodilator administration were strongly correlated with changes in forced expiratory volume at 1 second (FEV1) and forced expiratory flow at 25-75% (FEF25-75). However, the percentage changes in IOS parameters failed to discriminate between the asthma and COPD groups. Receiver operating characteristic curve (ROC) analysis of resistance at 5 and 20 Hz (R5-20) at the best cutoff (-15.4% change) showed both high sensitivity and specificity for BDR. CONCLUSIONS IOS serves as a reliable and useful technique for identifying BDR in elderly patients with chronic obstructive airway disease. There was a difference in IOS parameters between the asthma and COPD groups; however, it was difficult to distinguish between both diseases. Further larger studies are required to investigate the real implications of using IOS in the clinical practice.
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Affiliation(s)
- Jin-Han Park
- Department of Internal Medicine, Haeundae Paik Hospital, Inje University College of Medicine, Busan, Korea
| | - Jae Ha Lee
- Department of Internal Medicine, Haeundae Paik Hospital, Inje University College of Medicine, Busan, Korea
| | - Hyo-Jung Kim
- Department of Internal Medicine, Haeundae Paik Hospital, Inje University College of Medicine, Busan, Korea
| | - Nari Jeong
- Department of Internal Medicine, Haeundae Paik Hospital, Inje University College of Medicine, Busan, Korea
| | - Hang-Jea Jang
- Department of Internal Medicine, Haeundae Paik Hospital, Inje University College of Medicine, Busan, Korea
| | - Hyun-Kuk Kim
- Department of Internal Medicine, Haeundae Paik Hospital, Inje University College of Medicine, Busan, Korea
| | - Chan Sun Park
- Department of Internal Medicine, Haeundae Paik Hospital, Inje University College of Medicine, Busan, Korea
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Stockley JA, Cooper BG, Stockley RA, Sapey E. Small airways disease: time for a revisit? Int J Chron Obstruct Pulmon Dis 2017; 12:2343-2353. [PMID: 28848335 PMCID: PMC5557120 DOI: 10.2147/copd.s138540] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
It is increasingly acknowledged that delays in the diagnosis of chronic inflammatory lung conditions have hampered our understanding of pathogenesis and thus our ability to design efficacious therapies. This is particularly true for COPD, where most patients are diagnosed with moderate-to-severe airflow obstruction and little is known about the inflammatory processes present in early disease. There is great interest in developing screening tests that can identify those most at risk of developing COPD before airflow obstruction has developed for the purpose of research and clinical care. Landmark pathology studies have suggested that damage to the small airways precedes the development of airflow obstruction and emphysema and, thus, presents an opportunity to identify those at risk of COPD. However, despite a number of physiological tests being available to assess small airways function, none have been adopted into routine care in COPD. The reasons that tests of small airways have not been utilized widely include variability in test results and a lack of validated reference ranges from which to compare results for some methodologies. Furthermore, population studies have not consistently demonstrated their ability to diagnose disease. However, the landscape may be changing. As the equipment that delivers tests of small airways become more widely available, reference ranges are emerging and newer methodologies specifically seek to address variability and difficulty in test performance. Moreover, there is evidence that while tests of small airways may not be helpful across the full range of established disease severity, there may be specific groups (particularly those with early disease) where they might be informative. In this review, commonly utilized tests of small airways are critically appraised to highlight why these tests may be important, how they can be used and what knowledge gaps remain for their use in COPD.
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Affiliation(s)
| | | | | | - Elizabeth Sapey
- Institute of Inflammation and Ageing, Centre for Translational Inflammation Research, University of Birmingham, Edgbaston, Birmingham, UK
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Jarenbäck L, Eriksson G, Peterson S, Ankerst J, Bjermer L, Tufvesson E. Bronchodilator response of advanced lung function parameters depending on COPD severity. Int J Chron Obstruct Pulmon Dis 2016; 11:2939-2950. [PMID: 27932874 PMCID: PMC5135072 DOI: 10.2147/copd.s111573] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Background COPD is defined as partly irreversible airflow obstruction. The response pattern of bronchodilators has not been followed in advanced lung function parameters. Purpose The aim of this study was to investigate bronchodilator response pattern in advanced lung function parameters in a continuous fashion along forced expiratory volume in 1 second (FEV1) percent predicted (%p) in COPD patients and controls. Patients and methods Eighty-one smokers/ex-smokers (41 controls and 40 COPD) performed spirometry, body plethysmography, impulse oscillometry and single-breath helium dilution carbon monoxide diffusion at baseline, after salbutamol inhalation and then after an additional inhalation of ipratropium. Results Most pulmonary function parameters showed a linear increase in response to decreased FEV1%p. The subjects were divided into groups of FEV1%p <65 and >65, and the findings from continuous analysis were verified. The exceptions to this linear response were inspiratory capacity (IC), forced vital capacity (FVC), FEV1/FVC and expiratory resistance (Rex), which showed a segmented response relationship to FEV1%p. IC and FVC, with break points (BP) of 57 and 58 FEV1%p respectively, showed no response above, but an incresed slope below the BP. In addition, in patients with FEV1%p <65 and >65, response of FEV1%p did not correlate to response of volume parameters. Conclusion Response of several advanced lung function parameters differs depending on patients’ baseline FEV1%p, and specifically response of volume parameters is most pronounced in COPD patients with FEV1%p <65. Volume and resistance responses do not follow the flow response measured with FEV1 and may thus be used as a complement to FEV1 reversibility to identify flow, volume and resistance responders.
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Affiliation(s)
- Linnea Jarenbäck
- Respiratory Medicine and Allergology, Department of Clinical Sciences Lund, Lund University
| | - Göran Eriksson
- Respiratory Medicine and Allergology, Department of Clinical Sciences Lund, Lund University
| | - Stefan Peterson
- Regional Cancer Center South, Skåne University Hospital, Lund, Sweden
| | - Jaro Ankerst
- Respiratory Medicine and Allergology, Department of Clinical Sciences Lund, Lund University
| | - Leif Bjermer
- Respiratory Medicine and Allergology, Department of Clinical Sciences Lund, Lund University
| | - Ellen Tufvesson
- Respiratory Medicine and Allergology, Department of Clinical Sciences Lund, Lund University
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Crisafulli E, Pisi R, Aiello M, Vigna M, Tzani P, Torres A, Bertorelli G, Chetta A. Prevalence of Small-Airway Dysfunction among COPD Patients with Different GOLD Stages and Its Role in the Impact of Disease. Respiration 2016; 93:32-41. [PMID: 27852080 DOI: 10.1159/000452479] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Accepted: 10/11/2016] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND In chronic obstructive pulmonary disease (COPD) patients, small-airway dysfunction (SAD) is considered a functional hallmark of disease. However, the exact role of SAD in the clinical presentation of COPD is not yet completely understood; moreover, it is not known whether SAD may have a relationship with the impact of disease. OBJECTIVES To evaluate the prevalence of SAD among COPD patients categorized by the old and the new GOLD classification and to ascertain whether there is a relationship between SAD and impact of disease measured by the COPD Assessment Test (CAT) questionnaire. METHODS We prospectively enrolled COPD outpatients from the University Hospital of Parma. Using the impulse oscillometry system (IOS), we assessed the fall in resistance from 5 to 20 Hz (R5-R20), reactance at 5 Hz (X5), and resonant frequency (FRes) as markers of peripheral airway dysfunction. According to R5-R20 ≥0.07 or <0.07, the cohort was also categorized in patients with and without SAD, respectively. RESULTS We studied 202 patients. In both GOLD classifications, a progressive increasing distribution of R5-R20 and FRes was reported with a decreasing of X5. Moreover, there was a significant correlation between R5-R20 and CAT (r = 0.527, p < 0.001). Finally, the presence of SAD (OR 11.96; 95% CI 4.53-31.58; p < 0.001) and use of ICS + LABA + LAMA (OR 5.31; 95% CI 1.88-15.02; p = 0.002) were independent predictors of higher impact (CAT score ≥10). CONCLUSION In COPD patients, the presence of SAD, as assessed by IOS, progressively increases with GOLD classifications and it is closely related to the high impact of disease on health status.
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Affiliation(s)
- Ernesto Crisafulli
- Respiratory Disease and Lung Function Unit, Department of Clinical and Experimental Medicine, University of Parma, Parma, Italy
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Leitão Filho FS, Hang Chen H, Ngan DA, Tam A, Kirby M, Sin DD. Current methods to diagnose small airway disease in patients with COPD. Expert Rev Respir Med 2016; 10:417-429. [PMID: 26890226 DOI: 10.1586/17476348.2016.1155455] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The small airways are characterized by an internal diameter < 2 mm and absence of cartilage. Approximately 10-25% of total airway resistance in healthy lungs is due to the small airways, with their contribution to total airway resistance increasing substantially in chronic obstructive pulmonary disease (COPD). As the small airways are located in the lung periphery, they are not easily evaluable, which can potentially interfere with the diagnosis (especially at early stages), monitoring, detection of responses to clinical interventions, and prognostic evaluation in COPD. Here, we will discuss the currently available methods in clinical practice to evaluate small airway disease in COPD, focusing on the concept, advantages, and disadvantages of each method.
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Affiliation(s)
- Fernando Sergio Leitão Filho
- a Centre for Heart Lung Innovation, St. Paul´s Hospital, & Department of Medicine , University of British Columbia , Vancouver , British Columbia , Canada
| | - Hao Hang Chen
- a Centre for Heart Lung Innovation, St. Paul´s Hospital, & Department of Medicine , University of British Columbia , Vancouver , British Columbia , Canada
| | - David A Ngan
- a Centre for Heart Lung Innovation, St. Paul´s Hospital, & Department of Medicine , University of British Columbia , Vancouver , British Columbia , Canada
| | - Anthony Tam
- a Centre for Heart Lung Innovation, St. Paul´s Hospital, & Department of Medicine , University of British Columbia , Vancouver , British Columbia , Canada
| | - Miranda Kirby
- a Centre for Heart Lung Innovation, St. Paul´s Hospital, & Department of Medicine , University of British Columbia , Vancouver , British Columbia , Canada
| | - Don D Sin
- a Centre for Heart Lung Innovation, St. Paul´s Hospital, & Department of Medicine , University of British Columbia , Vancouver , British Columbia , Canada
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Gastaldi AC, Paredi P, Talwar A, Meah S, Barnes PJ, Usmani OS. Oscillating Positive Expiratory Pressure on Respiratory Resistance in Chronic Obstructive Pulmonary Disease With a Small Amount of Secretion: A Randomized Clinical Trial. Medicine (Baltimore) 2015; 94:e1845. [PMID: 26496331 PMCID: PMC4620777 DOI: 10.1097/md.0000000000001845] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
This study aims to evaluate the acute effects of an oscillating positive expiratory pressure device (flutter) on airways resistance in patients with chronic obstructive pulmonary disease (COPD).Randomized crossover study: 15 COPD outpatients from Asthma Lab-Royal Brompton Hospital underwent spirometry, impulse oscillometry (IOS) for respiratory resistance (R) and reactance (X), and fraction exhaled nitric oxide (FeNO) measures.Thirty minutes of flutter exercises: a "flutter-sham" procedure was used as a control, and airway responses after a short-acting bronchodilator were also assessed.Respiratory system resistance (R): in COPD patients an increase in X5insp (-0.21 to -0.33 kPa/L/s) and Fres (24.95 to 26.16 Hz) occurred immediately after flutter exercises without bronchodilator. Following 20 min of rest, a decrease in the R5, ΔR5, R20, X5, and Ax was observed, with R5, R20, and X5 values lower than baseline, with a moderate effect size; there were no changes in FeNO levels or spirometry.The use of flutter can decrease the respiratory system resistance and reactance and expiratory flow limitation in stable COPD patients with small amounts of secretions.
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Affiliation(s)
- Ada Clarice Gastaldi
- From the Physiotherapy Course, School of Medicine of Ribeirão Preto, São Paulo University, Brazil (ACG); Airway Disease Section, National Heart and Lung Institute, Imperial College London& Royal Brompton Hospital, United Kingdom (PP, SM, PJB, OSU); and Department of Physiology, All India Institute of Medical Sciences, India (AT)
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Kubaski F, Tomatsu S, Patel P, Shimada T, Xie L, Yasuda E, Mason R, Mackenzie WG, Theroux M, Bober MB, Oldham HM, Orii T, Shaffer TH. Non-invasive pulmonary function test on Morquio patients. Mol Genet Metab 2015; 115:186-92. [PMID: 26116954 PMCID: PMC4706533 DOI: 10.1016/j.ymgme.2015.06.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Revised: 06/19/2015] [Accepted: 06/20/2015] [Indexed: 12/13/2022]
Abstract
In clinical practice, respiratory function tests are difficult to perform in Morquio syndrome patients due to their characteristic skeletal dysplasia, small body size and lack of cooperation of young patients, where in some cases, conventional spirometry for pulmonary function is too challenging. To establish feasible clinical pulmonary endpoints and determine whether age impacts lung function in Morquio patients non-invasive pulmonary tests and conventional spirometry were evaluated. The non-invasive pulmonary tests: impulse oscillometry system, pneumotachography, and respiratory inductance plethysmography in conjunction with conventional spirometry were evaluated in twenty-two Morquio patients (18 Morquio A and 4 Morquio B) (7 males), ranging from 3 to 40 years of age. Twenty-two patients were compliant with non-invasive tests (100%) with the exception of IOS (81.8%-18 patients). Seventeen patients (77.3%) were compliant with spirometry testing. All subjects had normal vital signs at rest including >95% oxygen saturation, end tidal CO2 (38-44 mmHg), and age-appropriate heart rate (mean=98.3, standard deviation=19) (two patients were deviated). All patients preserved normal values in the impulse oscillometry system, pneumotachography, and respiratory inductance plethysmography, although predicted forced expiratory total (72.8±6.9 SE%) decreased with age and was below normal; phase angle (35.5±16.5°), %rib cage (41.6±12.7%), resonant frequency, and forced expiratory volume in 1 s/forced expiratory volume total (110.0±3.2 SE%) were normal and not significantly impacted by age. The proposed non-invasive pulmonary function tests are able to cover a greater number of patients (young patients and/or wheel-chair bound), thus providing a new diagnostic approach for the assessment of lung function in Morquio syndrome which in many cases may be difficult to evaluate. Morquio patients studied herein demonstrated no clinical or functional signs of restrictive and/or obstructive lung disease.
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Affiliation(s)
- Francyne Kubaski
- Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, USA; Department of Biological Sciences, University of Delaware, Newark, DE, USA
| | - Shunji Tomatsu
- Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, USA; Department of Pediatrics, Gifu University, Gifu, Japan.
| | - Pravin Patel
- Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, USA
| | - Tsutomu Shimada
- Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, USA
| | - Li Xie
- Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, USA
| | - Eriko Yasuda
- Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, USA
| | - Robert Mason
- Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, USA; Department of Biological Sciences, University of Delaware, Newark, DE, USA
| | | | - Mary Theroux
- Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, USA
| | - Michael B Bober
- Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, USA
| | - Helen M Oldham
- Department of Respiratory Care, Nemours/Alfred I. DuPont Hospital for Children, Wilmington, DE, USA
| | - Tadao Orii
- Department of Pediatrics, Gifu University, Gifu, Japan
| | - Thomas H Shaffer
- Nemours/Alfred I. duPont Hospital for Children, Wilmington, DE, USA; Center for Pediatric Lung Research, Nemours/Alfred I. DuPont Hospital for Children, Wilmington, DE, USA.
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Pisi R, Aiello M, Zanini A, Tzani P, Paleari D, Marangio E, Spanevello A, Nicolini G, Chetta A. Small airway dysfunction and flow and volume bronchodilator responsiveness in patients with chronic obstructive pulmonary disease. Int J Chron Obstruct Pulmon Dis 2015; 10:1191-7. [PMID: 26150710 PMCID: PMC4480584 DOI: 10.2147/copd.s82509] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Background We investigated whether a relationship between small airways dysfunction and bronchodilator responsiveness exists in patients with chronic obstructive pulmonary disease (COPD). Methods We studied 100 (20 female; mean age: 68±10 years) patients with COPD (forced expiratory volume in 1 second [FEV1]: 55% pred ±21%; FEV1/forced vital capacity [FVC]: 53%±10%) by impulse oscillometry system. Resistance at 5 Hz and 20 Hz (R5 and R20, in kPa·s·L−1) and the fall in resistance from 5 Hz to 20 Hz (R5 – R20) were used as indices of total, proximal, and peripheral airway resistance; reactance at 5 Hz (X5, in kPa·s·L−1) was also measured. Significant response to bronchodilator (salbutamol 400 μg) was expressed as absolute (≥0.2 L) and percentage (≥12%) change relative to the prebronchodilator value of FEV1 (flow responders, FRs) and FVC (volume responders, VRs). Results Eighty out of 100 participants had R5 – R20 >0.03 kPa·s·L−1 (> upper normal limit) and, compared to patients with R5 – R20 ≤0.030 kPa·s·L−1, showed a poorer health status, lower values of FEV1, FVC, FEV1/FVC, and X5, along with higher values of residual volume/total lung capacity and R5 (P<0.05 for all comparisons). Compared to the 69 nonresponders and the 8 FRs, the 16 VRs had significantly higher R5 and R5 – R20 values (P<0.05), lower X5 values (P<0.05), and greater airflow obstruction and lung hyperinflation. Conclusion This study shows that peripheral airway resistance is increased in the vast majority of patients with COPD, who showed worse respiratory reactance, worse spirometry results, more severe lung hyperinflation, and poorer health status. Small airway dysfunction was also associated with the bronchodilator responsiveness in terms of FVC, but not in terms of FEV1.
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Affiliation(s)
- Roberta Pisi
- Department of Clinical and Experimental Medicine, University of Parma, Parma, Italy
| | - Marina Aiello
- Department of Clinical and Experimental Medicine, University of Parma, Parma, Italy
| | - Andrea Zanini
- Division of Pneumology, IRCCS Rehabilitation Institute of Tradate, Salvatore Maugeri Foundation, Tradate, Italy
| | - Panagiota Tzani
- Department of Clinical and Experimental Medicine, University of Parma, Parma, Italy
| | - Davide Paleari
- Medical Department, Chiesi Farmaceutici SpA, Parma, Italy
| | - Emilio Marangio
- Department of Clinical and Experimental Medicine, University of Parma, Parma, Italy
| | - Antonio Spanevello
- Division of Pneumology, IRCCS Rehabilitation Institute of Tradate, Salvatore Maugeri Foundation, Tradate, Italy ; Department of Clinical and Experimental Medicine, University of Insubria, Varese, Italy
| | - Gabriele Nicolini
- Corporate Clinical Development, Chiesi Farmaceutici SpA, Parma, Italy
| | - Alfredo Chetta
- Department of Clinical and Experimental Medicine, University of Parma, Parma, Italy
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