An observational study in Asthma Chronic and Vocal Cord Dysfunction, sponsored by Haukeland University Hospital. Completed at 1 site in Norway. Open to participants aged 18 Years to 70 Years. Per ClinicalTrials.gov, last updated 2025-11-21.
Sponsored by Haukeland University Hospital · Observational
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, .
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.
18 studies on the registry are indexed under Vocal Cord Dysfunction; 4 are open to participants now.
Browse Vocal Cord Dysfunction studies →Haukeland University Hospital is the lead sponsor of 284 studies on the registry; 59 are open to participants now.
Counted across the registry records on this site, refreshed daily.
The sample size of the cohort with severe asthma will be: All patients with severe asthma followed in our clinic for severe asthma estimated to be around 80 participants, of them, we hope to recruit at least 40 to perform the CLE-test, and we plan to recruit 40 participants with mild asthma and 40 age- and gender matched control subjects without asthma
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Gina-guidlines treatment-step 5
Diagnostic Test: Continous laryngoscopy exercise test · Diagnostic Test: Overnight respiratory polygraphy
Gina-guidlines treatment-step 1-4
Diagnostic Test: Continous laryngoscopy exercise test · Diagnostic Test: Overnight respiratory polygraphy
Matches control-group without asthma
Diagnostic Test: Continous laryngoscopy exercise test · Diagnostic Test: Overnight respiratory polygraphy
Participants walks on a tredmill with a a flexible naso-laryngoscope in the larynx allowing visulasion of the larynx and obstructions in the larynx at the epiglottic og glottic levels are scored
Overnight respiratory polygraphy is a continuous recording of nasal airflow, thoracic and abdominal movements, heart rate and oxygen saturation during the night used to detected sleep apnoea
Prevalence of ILO in the participants
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.
Time frame: One year
Changes in continues during exercise (CLE-)-test score
The absolute change from baseline CLE-score (Score range 0 minimum -3 maximum). 3 is full closure in larynx, 0 is open.
Time frame: One year
The prevalence of OSA in asthma patients with ILO.
Prevalence of mild ( apnea-hypopnea index (AHI )5-15 ) moderat (AHI 15-30) and severe (AHI \> 30 )OSA in participents with asthma and ILO
Time frame: One year
Changes in asthma-controll score (ACT)
Changes of 3 points of ACT-score are considered a clinical relevant change, score (score range minimum 5, maximum 25)
Time frame: One year
Number of asthma-exercabations
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.
Time frame: One year
Changes in mini-Asthma quality of life (m-AQLQ)
Changes of 0.5 at m-AQLQ are considered a clinical relevant change
Time frame: One year
Plan to share: Undecided
This study is completed, as verified in May 2025. You cannot join it, but the record below documents what was studied.
Get an email when the registry record changes — status, dates, results — or when someone posts here.
Sign in to followQuestions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.
Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.
Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.
Haukeland University Hospital →