Inducible Laryngeal Obstruction in Severe Asthma in Severe Asthma

Active, not recruiting

• Conditions: Vocal Cord Dysfunction; Asthma Chronic
• Interventions: Diagnostic Test: Continous laryngoscopy exercise test; Diagnostic Test: Overnight respiratory polygraphy

• Registration Number: NCT04593394
• Lead Sponsor: Haukeland University Hospital

Brief Summary

The first part will be a comparative cross-sectional study to identify the frequency of ILO and other comorbidites among participants with asthma compared to a group of reference subjects without asthma, matched for age- and gender and race.

The second part will be a longitudinally observational study study following participants for one year after the cross-sectional study. The Maat-scores ILO-symptoms and asthma-outcomes longitudinally will be evaluated, .

Detailed Description

Inducible laryngeal obstruction (ILO) is characterized by inappropriate closure of the structures of the larynx causing reduced airflow. The symptoms are breathing difficulties that resemble those seen in asthmatic patients, such as dyspnea, coughing and stridor. ILO may be diagnosed by the continuous laryngoscopy during exercise test (CLE-test), where the larynx is visualized live on video as the patient runs to exhaustion on a treadmill whilst having a laryngoscope placed through the nose.

The prevalence of ILO in asthmatic patients will be assesed by preforming a CLE-test twice in all participants at baseline and again after one year. Participant will be given visual feedback and instructed in breathing techniques. Others common comorbidities will be assessed by questionnaires and clinical interview. All patients with asthma will have a respiratory polygraph recording.

Changes in ILO-symptoms and asthma-symptoms and outcomes will be assessed after 1 year.

Study Timeline

• Study First Submitted: 2020-10-13
• Study First Submitted QC: 2020-10-13
• Study First Posted: 2020-10-20
• Study Start: 2020-11-01
• Status Verified: 2024-03
• Last Update Submitted: 2024-03-06
• Last Update Posted: 2024-03-07
• Primary Completion: 2024-10-01
• Study Completion: 2024-10-01

Recruitment & Eligibility

• Status: ACTIVE_NOT_RECRUITING
• Sex: All
• Target Recruitment: 160

Inclusion Criteria

• Patients with severe asthma (GINA 5)
• Patients with mild-moderate well-treated asthma (GINA step 1-4)
• Agroup of age- and gender matched control subjects without asthma also aged 18- 70.
• The patients must have had a stable disease the last one month before performing the CLE-test

Exclusion Criteria

• No have underlying neurologic disease.
• No known cancer in the lung-head-neck
• No known vocal cord pathology.
• No history of life-threatening asthma required hospitalization.

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Arm && Interventions

Group	Intervention	Description
Severe asthma	Continous laryngoscopy exercise test	Gina-guidlines treatment-step 5
Subjects without asthma	Continous laryngoscopy exercise test	Matches control-group without asthma
Mild-moderate asthma	Overnight respiratory polygraphy	Gina-guidlines treatment-step 1-4
Severe asthma	Overnight respiratory polygraphy	Gina-guidlines treatment-step 5
Mild-moderate asthma	Continous laryngoscopy exercise test	Gina-guidlines treatment-step 1-4
Subjects without asthma	Overnight respiratory polygraphy	Matches control-group without asthma

Primary Outcome Measures

Name	Time	Method
Prevalence of ILO in the participants	One year	Continues during exercise(CLE)-test score at 2 or more at glottis or supraglottic level (Score range 0 minimum -3 maximum) 3 is full closure, 0 i open.
Changes in continues during exercise (CLE-)-test score	One year	The absolute change from baseline CLE-score (Score range 0 minimum -3 maximum). 3 is full closure in larynx, 0 is open.

Secondary Outcome Measures

Name	Time	Method
Changes in mini-Asthma quality of life (m-AQLQ)	One year	Changes of 0.5 at m-AQLQ are considered a clinical relevant change
The prevalence of OSA in asthma patients with ILO.	One year	Prevalence of mild ( apnea-hypopnea index (AHI )5-15 ) moderat (AHI 15-30) and severe (AHI \> 30 )OSA in participents with asthma and ILO
Changes in asthma-controll score (ACT)	One year	Changes of 3 points of ACT-score are considered a clinical relevant change, score (score range minimum 5, maximum 25)
Number of asthma-exercabations	One year	Annual asthma exacerbation rate and the precentage of patients with at least one asthma exacerbation. Asthma exacerbations are defined as worsening of asthma symptoms, and in participants on stable regimen with oral glucocorticoids, a doubling of the dose for 3 or more days or the use of systemic glucocorticoids for at least 3 days or beeing hospitalized.

Trial Locations

Locations (1)

Haukeland University Hospital; 🇳🇴 Bergen, Norway