Is small-airway dysfunction an abnormal phenomenon for patients with normal FEV1 and FEV1/FVC?

Abstract Background Subjects with chronic respiratory symptoms and preserved pulmonary function (PPF) may have small airway dysfunction (SAD). As the most common means to detect SAD, spirometry needs good cooperation and its reliability is controversial. Impulse oscillometry (IOS) may complete the deficiency of spirometry and have higher sensitivity. We aimed to explore the diagnostic value of IOS to detect SAD in symptomatic subjects with PPF. Methods The evaluation of symptoms, spirometry and IOS results in 209 subjects with chronic respiratory symptoms and PPF were assessed. ROC curves of IOS to detect SAD were analyzed. Results 209 subjects with chronic respiratory symptoms and PPF were included. Subjects who reported sputum had higher R5–R20 and Fres than those who didn’t. Subjects with dyspnea had higher R5, R5–R20 and AX than those without. CAT and mMRC scores correlated better with IOS parameters than with spirometry. R5, R5–R20, AX and Fres in subjects with SAD (n = 42) significantly increased compared to those without. Cutoff values for IOS parameters to detect SAD were 0.30 kPa/L s for R5, 0.015 kPa/L s for R5–R20, 0.30 kPa/L for AX and 11.23 Hz for Fres. Fres has the largest AUC (0.665, P = 0.001) among these parameters. Compared with spirometry, prevalence of SAD was higher when measured with IOS. R5 could detect the most SAD subjects with a prevalence of 60.77% and a sensitivity of 81% (AUC = 0.659, P = 0.002). Conclusion IOS is more sensitive to detect SAD than spirometry in subjects with chronic respiratory symptoms and PPF, and it correlates better with symptoms. IOS could be an additional method for SAD detection in the early stage of diseases.

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Air Trapping Is Associated with Heterozygosity for Alpha-1 Antitrypsin Mutations in Patients with Asthma

Respiration ◽

10.1159/000513072 ◽

2021 ◽

pp. 1-10

Author(s):

Marina Aiello ◽

Marianna Ghirardini ◽

Laura Marchi ◽

Annalisa Frizzelli ◽

Roberta Pisi ◽

...

Keyword(s):

Lung Function ◽

Serum Concentration ◽

Forced Expiratory Volume ◽

Small Airway ◽

University Hospital ◽

Air Trapping ◽

Asthmatic Patients ◽

Alpha 1 Antitrypsin Deficiency ◽

Alpha 1 Antitrypsin ◽

Few Data

Background: Alpha-1 antitrypsin deficiency (AATD) is a hereditary disorder involving lungs, characterized by low serum concentration of the protein alpha-1 antitrypsin (AAT) also called proteinase inhibitor (PI). Asthma is common in AATD patients, but there are only few data on respiratory function in asthmatic patients with AATD. Objectives: The aim of the study was to evaluate lung function in asthmatic outpatients with mutation in the SERPINA1 gene coding for AAT versus asthmatic subjects without mutation. Methods: We performed the quantitative analysis of the serum concentration of AAT in 600 outpatients affected by mild to moderate asthma from the University Hospital of Parma, Italy. Fifty-seven of them underwent the genetic analysis subsequently; they were subdivided into mutated and non-mutated subjects. All the mutated patients had a heterozygous genotype, except 1 (PI*SS). We assessed the lung function through a flow-sensing spirometer and the small airway parameters through an impulse oscillometry system. Results: The values of forced vital capacity (% predicted) and those of the residual volume to total lung capacity ratio (%) were, respectively, lower and higher in patients mutated versus patients without mutation, showing a significantly greater air trapping (p = 0.014 and p = 0.017, respectively). Moreover, patients with mutation in comparison to patients without mutation showed lower forced expiratory volume in 3 s (% predicted) and forced expiratory volume in 6 s (L) spirometric values, reflecting a smaller airways contribution. Conclusions: In asthmatic patients, heterozygosity for AAT with PI*MZ and PI*MS genotypes was associated with small airway dysfunction and with lung air trapping.

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Effects of Medication Use on Small Airway Function and Airway Inflammation in Patients with Clinically Controlled Asthma

Current Medical Science ◽

10.1007/s11596-021-2403-5 ◽

2021 ◽

Vol 41 (4) ◽

pp. 722-728

Author(s):

Yun Li ◽

Hong-ying Yu ◽

Kao-chuang Zhao ◽

Xu-hong Ding ◽

Yi Huang ◽

...

Keyword(s):

Airway Inflammation ◽

Medication Use ◽

Small Airway ◽

Airway Function

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Research on the Causes and Countermeasures of the Abnormal Phenomenon of Chinese University Students’ Learning Engagement

2020 International Symposium on Advances in Informatics, Electronics and Education (ISAIEE) ◽

10.1109/isaiee51769.2020.00021 ◽

2020 ◽

Author(s):

Shu Li ◽

Xiaoyuan Zhang ◽

Wei Wei ◽

Yueyang Zhang

Keyword(s):

University Students ◽

Learning Engagement ◽

Chinese University ◽

Abnormal Phenomenon ◽

Chinese University Students

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AB0597 PULMONARY FUNCTION IN PATIENTS DIAGNOSED OF EARLY SYSTEMIC SCLEROSIS: A NEW TOOL FOR SYSTEMIC SCLEROSIS CLASIFFICATION?

Annals of the Rheumatic Diseases ◽

10.1136/annrheumdis-2020-eular.4423 ◽

2020 ◽

Vol 79 (Suppl 1) ◽

pp. 1595.1-1595

Author(s):

F. M. Ortiz Sanjuan ◽

C. Pávez Perales ◽

E. Vicens Bernabeu ◽

C. Alcañiz Escandell ◽

I. Cánovas Olmos ◽

...

Keyword(s):

Systemic Sclerosis ◽

Pulmonary Function ◽

Airway Obstruction ◽

Pulmonary Involvement ◽

Classification Criteria ◽

Small Airway ◽

University Hospital ◽

Ventilatory Pattern ◽

Small Airway Obstruction

Background:Interstitial lung disease (ILD) is a frequent complication of systemic sclerosis (SSc) and is often progressive and has a poor prognosis. A restrictive ventilatory defect could suggest ILD either alone or in combination with pulmonary arterial hypertension.Nowadays, Early-SSc is well defined as preliminary stage of SSc. Patients who meet criteria for Early-SSc could benefit from an early diagnosis of pulmonary involvement.Objectives:Our aim was to assess the pulmonary function in patients diagnosed of Early SSc.Methods:Retrospective observational study of a wide and unselected series of patients diagnosed as Early-SSc from a single university hospital from 2012 to 2019. Patients were classified as Early-SSc following Le Roy criteria. Despite this, patients already did not meet 2013 ACR/EULAR classification criteria for SSc. We reviewed pulmonary function through conventional spirometry and diffusing capacity of lung for carbon monoxide (DLCO).Results:We included 56 patients with a mean age of 52.3±12.1 years (96.4% women; 3.6% men).At the diagnosis of Early-SSc, no one of our patients evidenced a restrictive ventilatory pattern. DLCO was below normal limits in 18 patients (32.1%). Small airway obstruction expressed according decreased maximal (mid-) expiratory flow (MMEF) 25-75 was present in 24 patients (42.8%).After a mean follow-up period of 38.3±2.4 months, 29 (51.8%) patients fulfilled 2013 ACR/EULAR criteria. The average time between diagnosis of Early-SSc and achieve SSc classification was 24.4±1.8 months. The remaining 27 patients continued classified as Early-SSc.An analysis of the subgroup of patients which progressed to SSc showed that DLCO was decreased in 15 of those 29 patients (51.7%) and 18 of 29 patients (62.1%) presented decreased MMEF 25-75. Comparing with the subgroup of patients which not progressed to SSc were significant differences (Decreased DLCO: 51.7% vs 11.1%; p=0.02 and decreased MMEF 25-75: 42.8% vs 22.2%; p=0.05).The analysis of pulmonary function of the subgroup of patients continued classified as Early-SSc after follow-up period did not show significative changes after follow-up.Conclusion:In our study, a third of the patients classified as Early-SSc presented at diagnosis abnormal values of DLCO and/or signs of small airway obstruction without the presence of a restrictive ventilatory pattern. Moreover, this pulmonary disfunction was significantly more frequent in patients who progressed to definitive SSc. Patients which remains classified as Early-SSc did not experience significative changes.Our results support the concept that pulmonary function was impaired in Early-SSc and that I should probably be considered for future Early-SSc classification criteria.Disclosure of Interests:None declared

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