The Prevalence Of Small Airways Dysfunction In Asthma Patients And The Impact On The Asthma Control

Status

UNKNOWN

Phases

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT04375995

Enrollment

108

Registered

2020-05-06

Start date

2019-10-01

Completion date

2021-04-01

Last updated

2020-05-06

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Asthma, Small Airway Disease

Keywords

Asthma, Small Airway Dysfunction, Impulse oscillometry

Brief summary

Asthma, which are one of the most important causes of morbidity and mortality both in the world and in our country, constitute a very serious social and economic burden. An estimated 300 million people suffer from asthma worldwide, which is a major public health problem. Asthma is complex and heterogeneous chronic airway diseases that require a multifaceted approach. In asthma, small airways represent key regions of airflow obstruction. Although small airway dysfunction is known in chronic airway diseases, the importance of small airway dysfunction on disease control, exacerbations and quality of life, and the importance of taking place among treatable targets is not clear. Thus, there is an unmet need to assess its role in the control of the disease. Therefore, our primary aim in the study is to determine the frequency of small airway dysfunction measured by impulse oscillometry in Asthma patients. Our secondary aim is to evaluate the role of small airway dysfunction in disease severity, disease phenotypes, disease control, quality of life and its effect on predicting the risk of exacerbation and its role among treatable targets in Asthma.

Detailed description

This is a prospective cross-sectional interventional design. 73 asthmatic patients who applied to Mersin University Faculty of Medicine Hospital Chest Diseases Clinic between 01.10.2019-01.04.2020 will be taken. 35 healthy volunteers who were admitted to our clinic within the same date range will be taken as control group. Impulse oscillometric pulmonary function tests will be performed to all participants. Thorax computed tomography will be performed to evaluate small airway dysfunction. To evaluate the degree of disease inflammation and phenotype in asthma patients, nitric oxide measurements will be made in the breath air with fractional exhaled nitric oxide (FENO) device. The blood eosinophil level will be studied to determine the asthma phenotype.Asthma control test (ACT) will be applied to measure symptom control in patients with asthma. Asthma quality of life scale (AQLQ) will be applied to determine the quality of life in asthmatic patients. All patients will be followed for 1 year to record the number of exacerbations requiring emergency and hospital admissions for asthma. The effect of small airway dysfunction on asthma group, on the disease severity and control degree, disease phenotypes and quality of life, and the effect on the risk of exacerbation will be analyzed.

Interventions

DIAGNOSTIC_TESTImpulse oscillometry

Impulse oscillometry test will be applied to all groups.

DIAGNOSTIC_TESTSpirometric pulmonary function test

Spirometric pulmonary function test will be applied to all groups.

DIAGNOSTIC_TESTFractional exhaled nitric oxide (FENO) test

FeNO test will be applied to asthma group.

DIAGNOSTIC_TESTThorax Computed Tomography

Thorax Computed Tomography will be taken to the asthma group.

DIAGNOSTIC_TESTBlood eosinophil level

The blood eosinophil level will be evaluated to determine the phenotype in the asthma group.

OTHERAsthma control test

Asthma control test questions will be applied to the asthma group.

OTHERAsthma quality of life scale

Asthma quality of life scale (AQLQ) will be applied to the asthma group.

DIAGNOSTIC_TESTChest X Ray

Chest X Ray will be applied to the healthy control group.

Study design

Allocation

NON_RANDOMIZED

Intervention model

SEQUENTIAL

Primary purpose

DIAGNOSTIC

Masking

NONE

Eligibility

Sex/Gender

ALL

Age

18 Years to No maximum

Healthy volunteers

Yes

Inclusion criteria

Asthma group * Participants who applied to the chest diseases clinic of Mersin University Hospital, between October 1, 2019 and April 1, 2020 * Participants who were diagnosed asthma with spirometry test * Reading and signing Informed Consent Form * Participants must be older than 18 years Healthy control group * To apply to the chest diseases clinic of Mersin University Hospital between October 1, 2019 and April 1, 2020 * Reading and signing informed consent form * Participants must be older than 18 years * Must have no lung disease * Must have no smoking history

Exclusion criteria

* Participants who do not sign the Informed Consent Form * Under the age of 18 years * Pregnant women * Participants who with a history of cancer in the past 5 years * Participants who previously had lung surgery * Participants who with Interstitial Lung Disease * Participants who with respiratory muscle disease * Participants who with active pulmonary tuberculosis * Participants who can not perform respiratory function tests

Design outcomes

Primary

Measure	Time frame	Description
Forced expiratory volume in 1 second (fev1) change will be evaluated by spirometric pulmonary function test.	through study completion, an average of 1 year	Forced expiratory volume in 1 second (fev1) change over one year period will be evaluated with spirometric pulmonary function test during recruitment and 1st year of follow-up.
Small airway dysfunction will be evaluated by body plethysmography test.	through study completion, an average of 1 year	Residual volume (RV) and total lung capacity (TLC) will be measured by body plethysmography test to determine small airway dysfunction.
Symptom control will be evaluated by asthma control test.	through study completion, an average of 1 year	The asthma control test consists of 5 questions.
The number of moderate and severe exacerbations over a 1 year period will be recorded.	through study completion, an average of 1 year	In the asthma group, each participant will be followed for 1 year in terms of recording exacerbations.
Small airway dysfunction will be evaluated by performing impulse oscillometry test.	through study completion, an average of 1 year	We will used respiratory resistance at 5 and 20 Hz (R5 and R20, respectively) for the analyses. R5 and R20 are regarded as reflecting total and proximal airway resistance, respectively, and the fall in resistance from R5 to R20 (R5-R20) will used as a surrogate for the resistance of small airways.
Small airway dysfunction will be evaluated by thorax computed tomography.	through study completion, an average of 1 year	Indirect changes caused by the small airways on the lung parenchyma will be detected by computed tomography (CT).

Secondary

Measure	Time frame	Description
Fractional Exhaled Nitric Oxide (FENO) test will be used as an indicator of inflammation in determining the relationship between airway inflammation and small airway dysfunction.	through study completion, an average of 1 year	FENO test is indirect measurements of inflammation, as used in clinical practice.
The relationship between blood inflammation cells and small airway dysfunction will be evaluated by complete blood count ( CBC).	through study completion, an average of 1 year	Blood eosinophil and neutrophil levels will be recorded.
Quality of life will be evaluated by Asthma Quality of Life Questionnaire (AQLQ).	through study completion, an average of 1 year	Asthma Quality of Life Questionnaire (AQLQ) contains 32 questions.

Countries

Turkey (Türkiye)

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026