Effects of Compression Stockings in Asthma Symptoms at Night

Study Overview
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Brief Summary
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Nocturnal worsening of asthma is common. It is characterized by overnight exacerbation of asthma symptoms such as shortness of breath, chest tightness, coughing, and wheezing, increased need of asthma medications and airway hyperresponsiveness, and decline in lung function (1). Nocturnal asthma has been attributed in part to circadian variations in lung function and airway inflammation. However, other factors including sleep, supine posture and lung volume may also contribute to nocturnal asthma. Current treatments often improve nighttime asthma symptoms. Nevertheless, nocturnal asthma is still common. Up to 2/3rd of asthma patients report nocturnal asthma symptoms, and many asthma related events occur at night, indicating poor asthma control. Results from an ongoing study suggest that in asthma while subjects were supine, fluid shifted out of the legs and accumulated in the thorax (rostral fluid shift) contributing to lower airway narrowing in asthma. A previou study has shown that wearing compression stockings during the day reduces fluid retention in the legs, reduces nocturnal rostral fluid shift out of the legs, and improves sleep apnea (2, 3). The aims of the proposed study is investigate whether off-the-shelf, below the knee compression stockings will attenuate nocturnal fluid shift and lower airway narrowing in asthma.

Official Title
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Investigating the Effects of Wearing Compression Stockings to Improve Asthma Symptoms at Night

Conditions
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Asthma

Intervention / Treatment
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* Other: Compression Stockings
* Other: Control


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: non-smokers or former smokers (<10 pack/year) Exclusion Criteria: history of hypertension, or taking any prescribed medication for this disorder.

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 75 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Crossover Assignment
Interventional Model Description: Participants will be randomly assigned to wearing compression stockings for next two weeks or not wearing compression stockings for next two weeks, and crossed over.
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Asthma group<br>Participants will be randomized to wear compression stockings or to control group for two weeks and cross over in the end of the period. When assigned to wear compression stockings, they will be instructed to put the stockings on as soon as they get up in the morning and to remove them just prior to bedtime for two weeks. If they have become loose, a new pair will be fitted. They will be given a diary to record the time they put on and remove the compression stockings each day. They will be telephoned after one week to check the fit of the compression stockings. | Other: Compression Stockings<br>* We will use knee length, ready-made compression stockings at a pressure of 20-30mmHg at the ankle and if a good fit cannot be obtained, custom-made stockings will be ordered. Patients will be measured for compression stockings by a certified fitter.<br>Other: Control<br>* Participants will not wearing compression stockings for two weeks.<br>|
| Active Comparator: Healthy group<br>Participants will be randomized to wear compression stockings or to control group for two weeks and cross over in the end of the period. When assigned to wear compression stockings, they will be instructed to put the stockings on as soon as they get up in the morning and to remove them just prior to bedtime for two weeks. If they have become loose, a new pair will be fitted. They will be given a diary to record the time they put on and remove the compression stockings each day. They will be telephoned after one week to check the fit of the compression stockings. | Other: Compression Stockings<br>* We will use knee length, ready-made compression stockings at a pressure of 20-30mmHg at the ankle and if a good fit cannot be obtained, custom-made stockings will be ordered. Patients will be measured for compression stockings by a certified fitter.<br>Other: Control<br>* Participants will not wearing compression stockings for two weeks.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Effect of wearing compression stockings on reducing rostral fluid shift during sleep and its effect in airway narrowing | Effect of wearing compression stockings or not on reducing fluid retention in the legs, reducing rostral fluid shift during sleep and improving nocturnal lower airway narrowing in asthma. After 2 weeks using or not compression stockings we will measure the overnight fluid volumes changes in leg, thorax and neck; changes in the respiratory impedance, pulmonary diffusion capacity and lung volume pre and post night of sleep | After 2 weeks of the intervention | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Asthma, Fluid Shift, Compression stockings, intrathoracic airway narrowing