Effectiveness of Compression Stocking on Overnight Fluid Shift in Obstructive Sleep Apnoea Patients

Study Overview
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Brief Summary
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Overnight rostral fluid shift is one of the contributing factors for worsening obstructive sleep apnoea (OSA). Fluid shift has been recognized to play a role in the pathophysiology of sleep apnoea. Previous studies shown that fluid from the leg redistributes to the neck at night increases the neck circumference, hence indicating fluid accumulation in the neck. OSA patients are more susceptible to developing upper airway narrowing in response to fluid shift from the leg to the head and neck region. Previous studies were mainly done on Caucasian patients. The pathophysiology of OSA in Caucasian patients and Asian patients are different but both suffer a similar degree of OSA. The investigators would like to investigate if reducing leg swelling by a simple non-invasive intervention of wearing compression stocking during the day can attenuate sleep apnoea, and whether compression stocking is generally acceptable and well-tolerated among the general OSA population in Asia.

Official Title
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Effectiveness of Compression Stocking on Overnight Fluid Shift in Obstructive Sleep Apnea Patients

Conditions
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Obstructive Sleep Apnea

Intervention / Treatment
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* Device: Compression stocking


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Aged 30 years old to 65 years old. Either STOP-Bang score of ≥3 or Epworth sleepiness scale indicating mild excessive daytime sleepiness to severe excessive daytime sleepiness (11-24 points). Has pre-existing diabetes mellitus and/or hypertension and is on medication. Ability to provide informed consent. Not working night shift. Exclusion Criteria: Significant arterial disease due to the risk of limb ischaemia and necrosis. Not pregnant and not planning to get pregnant before the end of the study. History of psychiatric disease. Patient who are on wheelchair. Patient who has cardiac failure and or stroke. Patient who has end-stage renal failure. Estimated glomerular filtration rate <15ml/min/1.73m2 or on renal replacement therapy i.e. dialysis or renal transplant. Patient who has liver disease. Patient who are on pacemaker, and metal implants. Patient who are on CPAP treatment for OSA. Patient who are illiterate. Medications which affect fluid balance or level of consciousness (e.g. diuretics, non- steroidal anti-inflammatory drugs (NSAIDS), corticosteroids, sedatives, opiates) at any time during the study.

Ages Eligible for Study
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Minimum Age: 30 Years
Maximum Age: 65 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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Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Below the knee compression stocking<br> | Device: Compression stocking<br>* A below-the-knee compression stock will be worn daily for 2 weeks from waking up to before sleep. Bioelectrical impedance will be performed before and 2 weeks after wearing the stocking to assess the total body water content. Measuring the calf and neck circumference will be done before and after wearing the compression stocking. After 2 weeks, the patient will return back to the clinic for calf and neck circumference measurement. Sleep test will be done the night before and 2 weeks after wearing the compression stocking. Oxygen Desaturation Index(ODI) will be assessed through a level 4 home sleep apnea testing device. Patients recruited will have mild excessive to severe excessive daytime sleepiness and/or STOP-Bang score of 3 or more, with underlying conditions such as type II diabetes and hypertensive patients using the Epworth sleepiness scale. Epworth sleepiness scale will be assessed again 2 weeks after to assess for increase sleep efficiency.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Compression stocking improves ODI of OSA patients | Bioelectrical impedance analysis (BIA) readings performed before wearing the compression stocking and 2 weeks after wearing the compression stocking to assess the total body water, lower limb total water content (LLW), lower limbs extracellular water content (ecLLW), trunk total water content (TW), trunk extracellular water content (ecTW), neck fluid volume and leg fluid volume will be improved. Calf and neck circumference measurements before wearing the compression stocking and 2 weeks after wearing the compression stocking will be improved. Sleep test done to measure the Oxygen Desaturation Index (ODI) the night before wearing the compression stocking and 2 weeks before the final visit to the clinic will be improved. | 2 weeks |