An interventional study of Continuous Laryngoscopy during Exercise Test (CLE test) in Exercise Induced Laryngeal Obstruction, Asthma in Children and Exercise-Induced Bronchospasm, sponsored by Medisch Spectrum Twente. Not yet recruiting at 1 site in Netherlands. Open to participants aged 12 Years to 18 Years. Per ClinicalTrials.gov, last updated 2024-06-28.
Sponsored by Medisch Spectrum Twente · Not applicable, Interventional, and Diagnostic
The goal of this cross-sectional study is to investigate the prevalence of Exercise Induced Laryngeal Obstruction (EILO) in children with asthma.
The hypothesis is that the prevalence will be around 15%, which is higher than the prevalence of 5-8% among the general adolescent population. This is based on the increased prevalence of EILO among adult asthmatics.
Participants who are referred for an Exercise Challenge Test will perform an additional Continuous Laryngoscopy during Exercise Test with expiratory FEV1 curves, and fill in the Borg scale for dyspnea, Asthma Control Test, EILODI questionnaire and DISCO-RC questionnaire.
Background:Exertional dyspnoea is a common and limiting symptom within the paediatric population. Regular physical activity is paramount for the development of children since it not only promotes cardiorespiratory fitness and muscle strength, but also offers opportunities for self-expression, building confidence and social interaction and integration. It is therefore important to identify the correct cause(s) of exertional dyspnea and reverse them to enable children to be active without symptoms.
Exercise induced bronchoconstriction (EIB) is a well-known cause of exertional dyspnoea and is highly specific of childhood asthma. Another less recognized cause of exertional dyspnoea is exercise induced laryngeal obstruction (EILO). EILO is an inappropriate closure of the larynx during strenuous physical activity with no obvious laryngeal pathology at rest, limiting airflow and causing inspiratory stridor. It can co-exist with and mimic symptoms of EIB.
Previous studies showed a prevalence of 6% in adolescent populations). However, recent studies revealed a much higher prevalence ofEILO in adults with asthma, up to 25-47%. The prevalence of EILO amongst children with asthma has not yet been investigated. In this study, the aim is to investigate the prevalence of EILO in children with asthma.
If EILO is a significant comorbidity of childhood asthma this would implicate that EILO screening should be considered when exercise is a persistent trigger of symptoms in asthmatic children. Correct EILO diagnosis and treatment can lead to adequate treatment of EILO, and to prevention of overtreatment of asthma.
Methods: Participants who are referred for an Exercise Challenge Test will perform an additional Continuous Laryngoscopy during Exercise Test with expiratory FEV1 curves, and fill in the Borg scale for dyspnea, Asthma Control Test, EILODI questionnaire and DISCO-RC questionnaire.
Power analysis: The sample size is calculated based on an estimated prevalence and confidence interval, with a power of 80% and alpha of 0.05. When estimating a prevalence of 15% (CI 10-20%), which is 2 times higher than in the general population (30), this results in a sample size of 196 participants. This was rounded to 200 participants. Dropouts will be replaced until a total number of 200 participants completed both the ECT and CLE test.
Statistical analysis for primary outcome: The prevalence of EILO in the study population of adolescents with asthma will be calculated as a percentage with a 95% confidence interval. Baseline characteristics will be compared between participants and non-participants of the CLE test. If there are no significant differences between these groups, it can be assumed that participants represent the studied population. If there are significant differences in baseline characteristics, we will examine the correlation of these characteristics with EILO. An estimated prevalence of EILO will be calculated among the non-participants based on these correlations, and an estimated weighted average will be calculated of the prevalence of EILO among the studied population.
52 studies on the registry are indexed under Asthma, Exercise-Induced; 3 are open to participants now.
This study's planned enrollment of 200 is above the median of 47 across 40 interventional studies indexed under Asthma, Exercise-Induced.
Browse Asthma, Exercise-Induced studies →Medisch Spectrum Twente is the lead sponsor of 23 studies on the registry; 10 are open to participants now.
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Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
From a breathing test (spirometry): how much air you can blow out in the first second. Often given as a percentage of what is expected for your age, height and sex.
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
FEV1
From a breathing test (spirometry): how much air you can blow out in the first second. Often given as a percentage of what is expected for your age, height and sex.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Corticosteroids (steroids)
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
A flexible fiberoptic laryngoscope (Olympus, Tokyo, Japan) is introduced directly through the nose or via a slightly modified Hans Rudolph facemask, and into the pharyngeal space. A modified Bruce protocol with a 60-second incremental intensity step is used (Appendix A) and heart rate is monitored. During the CLE test participants perform incremental exercise on a treadmill until symptom-limiting distress or exhaustion. Forced expiratory flow-volume loops are measured before, during and after the CLE test.
Prevalence of EILO
Prevalence of EILO (defined as Maat score grade 2 or higher) in study population, with 95% confidence interval
Time frame: During CLE test. Measured in period until 200 participants are enrolled, expected to be 2 years
Prevalence of EILO with and without current EIB
The prevalence of EILO among adolescents with and without current EIB will be calculated using a 2x2 table, including 95% confidence intervals. These prevalences will be compared with a Chi-Square test or Fisher's exact test.
Time frame: During CLE test which takes approximately one hour. Measured in period until 200 participants are enrolled, expected to be 2 years
Association of gender with presence of EILO
Baseline characteristics of adolescents with and without EILO will be compared. Association of gender with presence of EILO will be compared using a Chi-square or Fisher's exact test for categorical variables.
Time frame: During ECT and CLE test which each take approximately one hour. Measured in period until 200 participants are enrolled, expected to be 2 years
Association of age with presence of EILO
Baseline characteristics of adolescents with and without EILO will be compared. Association of age with presence of EILO will be compared using a T-test (or non-parametric Mann Whitney U test) for continuous variables
Time frame: During ECT and CLE test which each take approximately one hour. Measured in period until 200 participants are enrolled, expected to be 2 years
Association of length with presence of EILO
Baseline characteristics of adolescents with and without EILO will be compared. Association of length with presence of EILO will be compared using a T-test (or non-parametric Mann Whitney U test) for continuous variables
Time frame: During ECT and CLE test which each take approximately one hour. Measured in period until 200 participants are enrolled, expected to be 2 years
Association of weight with presence of EILO
Baseline characteristics of adolescents with and without EILO will be compared. Association of weight with presence of EILO will be compared using a T-test (or non-parametric Mann Whitney U test) for continuous variables
Time frame: During ECT and CLE test which each take approximately one hour. Measured in period until 200 participants are enrolled, expected to be 2 years
Association of BMI Z score with presence of EILO
Baseline characteristics of adolescents with and without EILO will be compared. Association of BMI Z score with presence of EILO will be compared using a T-test (or non-parametric Mann Whitney U test) for continuous variables
Time frame: During ECT and CLE test which each take approximately one hour. Measured in period until 200 participants are enrolled, expected to be 2 years
Association of hours of moderate-to-vigorous weekly activity with presence of EILO
Baseline characteristics of adolescents with and without EILO will be compared. Association of hours of moderate-to-vigorous weekly activity with presence of EILO will be compared using a T-test (or non-parametric Mann Whitney U test) for continuous variables
Time frame: During ECT and CLE test which each take approximately one hour. Measured in period until 200 participants are enrolled, expected to be 2 years
Association of athletic performance (none/local/regional/national/international) with presence of EILO
Baseline characteristics of adolescents with and without EILO will be compared. Association of athletic performance (none/local/regional/national/international) with presence of EILO will be compared using a Chi-square or Fisher's exact test for categorical variables.
Time frame: During ECT and CLE test which each take approximately one hour. Measured in period until 200 participants are enrolled, expected to be 2 years
Association of type of sports with presence of EILO
Baseline characteristics of adolescents with and without EILO will be compared. Association of type of sports with presence of EILO will be compared using a Chi-square or Fisher's exact test for categorical variables.
Time frame: During ECT and CLE test which each take approximately one hour. Measured in period until 200 participants are enrolled, expected to be 2 years
Association of medication use with presence of EILO
Baseline characteristics of adolescents with and without EILO will be compared. Association of medication use with presence of EILO will be compared using a Chi-square or Fisher's exact test for categorical variables.
Time frame: During ECT and CLE test which each take approximately one hour. Measured in period until 200 participants are enrolled, expected to be 2 years
Association of comorbidities with presence of EILO
Baseline characteristics of adolescents with and without EILO will be compared. Association of comorbidities with presence of EILO will be compared using a Chi-square or Fisher's exact test for categorical variables.
Time frame: During ECT and CLE test which each take approximately one hour. Measured in period until 200 participants are enrolled, expected to be 2 years
Association of recognizable symptoms with presence of EILO
Test characteristics of adolescents with and without EILO will be compared. Association of of recognizable symptoms with presence of EILO will be compared using a Chi-square or Fisher's exact test for categorical variables.
Time frame: During ECT and CLE test which each take approximately one hour. Measured in period until 200 participants are enrolled, expected to be 2 years
Association of type of reported symptoms with presence of EILO
Test characteristics of adolescents with and without EILO will be compared. Association of of type of reported symptoms with presence of EILO will be compared using a Chi-square or Fisher's exact test for categorical variables.
Time frame: During ECT and CLE test which each take approximately one hour. Measured in period until 200 participants are enrolled, expected to be 2 years
Association of heart rate during exercise with presence of EILO
Test characteristics of adolescents with and without EILO will be compared. Association of of heart rate during the exercise test with presence of EILO will be compared using a T-test (or non-parametric Mann Whitney U test)
Time frame: During ECT and CLE test which each take approximately one hour. Measured in period until 200 participants are enrolled, expected to be 2 years
Association of baseline FEV1 (% predicted) with presence of EILO
Test characteristics of adolescents with and without EILO will be compared. Association of of baseline FEV1 (% predicted) with presence of EILO will be compared using a T-test (or non-parametric Mann Whitney U test)
Time frame: During ECT and CLE test which each take approximately one hour. Measured in period until 200 participants are enrolled, expected to be 2 years
Association of maximal % post-exercise fall in FEV1 with presence of EILO
Test characteristics of adolescents with and without EILO will be compared. Association of of maximal % post-exercise fall in FEV1 with presence of EILO will be compared using a T-test (or non-parametric Mann Whitney U test)
Time frame: During ECT and CLE test which each take approximately one hour. Measured in period until 200 participants are enrolled, expected to be 2 years
Association of maximal exercise intensity (wattage/kg or maximum running pace and slope) with presence of EILO
Test characteristics of adolescents with and without EILO will be compared. Exercise intensity will be measured by wattage/kg or maximum running pace and slope and categorized into poor / average / good. Association of of exercise intensity with presence of EILO will be compared using a Chi-square or Fisher's exact test for categorical variables
Time frame: During ECT and CLE test which each take approximately one hour. Measured in period until 200 participants are enrolled, expected to be 2 years
Association of Asthma Control Test (ACT) with EILO
The ACT score and sub scores will be compared between adolescents with and without EILO using a T-test (or non-parametric Mann-Whitney U test). A receiver operating characteristic curve and 2x2 tables will be used to evaluate the sensitivity and specificity of different cut-off points of these questionnaires.
Time frame: During CLE test which takes approximately one hour. Measured in period until 200 participants are enrolled, expected to be 2 years
Association of Exercise-Induced Laryngeal Obstruction Dyspnea Index (EILODI) with EILO
EILODI score and sub scores will be compared between adolescents with and without EILO using a T-test (or non-parametric Mann-Whitney U test). A receiver operating characteristic curve and 2x2 tables will be used to evaluate the sensitivity and specificity of different cut-off points of these questionnaires.
Time frame: During CLE test which takes approximately one hour. Measured in period until 200 participants are enrolled, expected to be 2 years
Association of Visual Analogue Scale (VAS) with EILO
VAS scores will be compared between adolescents with and without EILO using a T-test (or non-parametric Mann-Whitney U test). A receiver operating characteristic curve and 2x2 tables will be used to evaluate the sensitivity and specificity of different cut-off points of these questionnaires.
Time frame: During CLE test which takes approximately one hour. Measured in period until 200 participants are enrolled, expected to be 2 years
Association of combination of questionnaire scores (Asthma Control Test (ACT), Exercise-Induced Laryngeal Obstruction Dyspnea Index (EILODI) and/or Visual Analogue Scale (VAS)) with EILO
Questionnaire scores (ACT, EILODI, and/or VAS) and sub scores will be compared between adolescents with and without EILO using a T-test (or non-parametric Mann-Whitney U test). A receiver operating characteristic curve and 2x2 tables will be used to evaluate the sensitivity and specificity of different cut-off points of these questionnaires.
Time frame: During CLE test which each take approximately one hour. Measured in period until 200 participants are enrolled, expected to be 2 years
Assesment of EIB with CLE compared to ECT test
Lung function measurements during the CLE test will be compared to lung function measurements during the ECT using a Bland-Altman plot. A 2x2 table will be made of EIB presence during the ECT and CLE test and outcomes will be compared using a Chi-Square test.
Time frame: During ECT and CLE test which each take approximately one hour. Measured in period until 200 participants are enrolled, expected to be 2 years
Comparison of age between participants with similar and non-similar EIB results during CLE and ECT test
Age will be compared between participants with similar and non-similar results during the ECT and CLE test using a T-test, or a non-parametric Mann-Whitney U test
Time frame: During ECT and CLE test which each take approximately one hour. Measured in period until 200 participants are enrolled, expected to be 2 years
Comparison of test duration between participants with similar and non-similar EIB results during CLE and ECT test
Test duration will be compared between participants with similar and non-similar results during the ECT and CLE test using a T-test, or a non-parametric Mann-Whitney U test
Time frame: During ECT and CLE test, which each take approximately one hour. Measured in period until 200 participants are enrolled, expected to be 2 years
Comparison of heart rate between participants with similar and non-similar EIB results during CLE and ECT test
Heart rate will be compared between participants with similar and non-similar results during the ECT and CLE test using a T-test, or a non-parametric Mann-Whitney U test
Time frame: During ECT and CLE test, which each take approximately one hour. Measured in period until 200 participants are enrolled, expected to be 2 years
Inter-rater agreement of EILO diagnosis between two participating hospitals
Inter-rater agreement of the presence of EILO and the Maat score of laryngoscopical images of the larynx, between both hospitals will be described using Cohen's weighted x.
Time frame: During CLE test, which takes approximately one hour. Measured in period until 200 participants are enrolled, expected to be 2 years
Self-reported discomfort of CLE test
The self-reported discomfort during the CLE test will be calculated based on the DISCO-RC questionnaire scores.
Time frame: After the CLE test, which takes approximately one hour. Measured in period until 200 participants are enrolled, expected to be 2 years
Plan to share: No
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Start is estimated for Aug 2024; primary completion for Apr 2026, 20 months later.
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