Predictors of Asthma Exacerbations in Children

Study Overview
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Brief Summary
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The purpose of this study is to determine whether parameters of the pulmonary function tests and the bronchial hyperresponsiveness to methacholine are predictors of asthma exacerbations.

Detailed Description
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Preliminary investigations from our own research group showed that lung function parameters (FEV1, the FEV1/FVC ratio and a moderate to severe hyperresponsiveness to methacholine challenge were risk factors of asthma exacerbations (OR 11.3). In the present study, these parameters will be evaluated in prospective design. One hundred children will be included in the study. Baseline parameters will be collected in a healthy interval (visit 1), then the children will be followed up for 1 year. If the patients fulfill the criteria for an exacerbation the children will present in our department. We expect that 44% of the children have an exacerbation. All children will present at a second visit after one year (visit 2).

Official Title
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Asthma Exacerbations in Young Children With Moderate Asthma - Prospective Evaluation of Predictors

Conditions
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Asthma

Intervention / Treatment
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* Other: Methacholine challenge testing


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Informed consent Age >3 and <7 years Diagnosis of intermittent asthma In the last 24 months, at least 6 weeks of treatment with a controller medication (inhaled steroid and / or leukotriene receptor antagonist Singulair ®), or in the last 12 months, at least three episodes with an use of controller medications (inhaled steroid and / or the leukotriene receptor antagonist Singulair ®) The ability to perform three reproducible spirometries Examination in infection-free interval (> 4 weeks infection-free) Minimum distance to the following asthma medications: Short-acting beta 2-agonists: 8 hours Ipratropium bromide: 24 hours Long-acting beta 2-agonists: 24 hours steroids: 4 weeks leukotriene antagonist: 4 weeks Exclusion Criteria: Age older than 6 years or younger than 4 The inability to perform spirometry Other chronic diseases or infections (eg. HIV, tuberculosis, malignancy) Participation in another study

Ages Eligible for Study
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Minimum Age: 4 Years
Maximum Age: 6 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Intervention/Treatment |
| --- |
|Other: Methacholine challenge testing|Nebulized methacholine administered at the following doses: 0,1 mg/0,4 mg/0,8 mg/1,6 mg|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of exacerbations | An exacerbations is defined as an increased need of salbutamol (more than two puffs per week or more than five puffs per two weeks). In this case patients will be followed up at our hospital and will start an anti-inflammatory therapy, if it is necessary. | 1 year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Predictors of exacerbations like lung function, nonspecific bronchial hyperresponsiveness to methacholine, exhaled NO, specific IgE, total IgE und ECP |  | 1 year | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Asthma, children, predictors of exacerbation, Methacholine challenge, Pulmonary function testing