Exercise-induced Asthma
Conditions
Keywords
exercise-induced bronchoconstriction, exercise-induced asthma, cold chamber, exercise challenge, cold air challenge, combined exercise- and cold-air challenge, methacholine challenge
Brief summary
The purpose of this study is to compare the exercise-challenge in a cold chamber at 2-4°C to the gold standard the metacholine challenge in subjects showing symptoms of exercise-induced bronchoconstriction. The sensitivity and repeatability of the exercise test will be measured.
Detailed description
Subjects suffering form exercise-induced bronchoconstriction (EIB) usually have a normal lung function testing at rest. To provoke asthma symptoms a provocation test is necessary, e.g., by bronchial methacholine testing or by a standardised exercise test on a treadmill. The correlation between methacholine and exercise test is fair, possibly because both methods measure different kinds of bronchial hyperresponsiveness. Moreover, the sensitivity and the repeatability of the exercise test is fair. The value of the methacholine test to predict a positive exercise test will be measured. We hypothesize that the exercise test in a cold chamber, a combination of two provocation methods cold air and exercise, is more sensitive to detect EIB and that the test has a better repeatability.
Interventions
Exercise challenge is defined as running on a treadmill for 6-8 minutes on submaximal work load in a cold chamber.
nebulized metacholine administered at following doses: 0,01mg, 0,1mg, 0,4mg, 0,8mg und 1,6mg
OTHERExercise challenge in room temperature
Exercise challenge is defined as running on a treadmill for 6-8 minutes on submaximal work load in room temperature.
Sponsors
Johann Wolfgang Goethe University Hospital
Study design
Allocation
NON_RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
DIAGNOSTIC
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
6 Years to 45 Years
Healthy volunteers
No
Inclusion criteria
* Informed consent * Patients: Age \>6 and \<18 years * Subjects: Age \>/=18 and \<45 years * sportive, 1-2x exercise per week * bronchial hyperresponsiveness in the medical history
Exclusion criteria
* lung function Forced vital capacity (FVC) \<80% and Forced expiratory volume in 1 second (FEV1) \<75% * chronic diseases or infections (e.g. HIV, Tbc) * pregnancy * systemic corticosteroid-treatment * inhalative corticosteroid therapy or leukotriene antagonists \<14d * alcohol, substance or drug abuse * smokers * inability to capture extend and consequences of the study
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Agreement of metacholine challenge and the combined exercise/cold-air challenge | 3 months | Lung function will be measured prior and after methacholine- and exercise/cold-air challenges. The maximal fall in forced expiratory volume in one second (FEV1, percent predicted) after methacholine and cold air challenge will be compared by statistical correlation. For both methods the sensitivity and the specificity to predict an exercise induced asthma will be calculated by a receiver operating characteristic (ROC analysis). All subjects receive Salbutamol to relief them from bronchial constriction at the end of the test. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Repeatability of the combined exercise/cold-air challenge | 3 months | The combined exercise/cold-air challenge will be performed twice within one week. Post challenge the FEV1 will be measured after 5, 10, 20, and 30 minutes. The maximal fall in FEV1 (percent predicted) and the area under the curve (AUC) will be compared. The agreement and the repeatability of the maximal fall in FEV1 and of the AUC will be measured by correlation and by the method of Bland and Altman. |
Other
| Measure | Time frame | Description |
|---|---|---|
| Agreement of the combined exercise/cold-air challenge with the Asthma-score | 3 months | All children who participate will fill the asthma control test (ACT) and all adult subjects will fill the asthma control questionnaire (ACQ). The asthma-score will be compared with the severity of the exercise induced asthma measured by the maximal fall in FEV1. |
Countries
Germany
Outcome results
None listed