Effects of Compression Stockings on Obstructive Sleep Apnea in Patients Under Hemodialysis

Study Overview
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Brief Summary
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To study the effects of compression stockings on sleep apnea in hemodialysis patients with diagnosed obstructive sleep apnea. The rationale of this study consists in the fluid shift theory, which consists in the nocturnal rostral fluid shift from legs, which causes upper airways edema. The aim of this study is to evaluate if compression stockings could improve such nocturnal volume redistribution and, therefore, improve obstructive sleep apnea.

Detailed Description
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Investigators will apply the following methods: Sleep study, performed through polysomnography Fluid redistribution, by bioimpedance analysis Autonomic nervous system evaluation, by spectral heart rate variability analysis. The study protocol comprises two moments: baseline evaluation (in patients with diagnosed sleep apnea) and after using compression stockings for a one-week period.

Official Title
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Effects of Compression Stockings on Obstructive Sleep Apnea and Autonomic Nervous System in Patients Under Hemodialysis

Conditions
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Renal Failure Chronic Requiring Dialysis, Obstructive Sleep Apnea

Intervention / Treatment
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* Device: Compression Stockings


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients under hemodialysis Patients with diagnosed obstructive sleep apnea Exclusion Criteria: Congestive heart failure Urine output > 500 ml/day non-sinusal cardiac rhythm refusal to give written consent

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 70 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: Compression Stockings<br>Patients will wear graduated lower limb compression stockings for a week. The investigators will evaluate if such procedure will cause better sleep performance | Device: Compression Stockings<br>* To evaluate the effects of compression stockings on fluid shift and sleep apnea in hemodialysis patients with obstructive sleep apnea<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change of Obstructive Apnea Severity Index Score From Baseline | Apnea/Hypopnea index (AIH) was assessed by a validated polysomnography (EMBLA®S4500, Embla Systems Inc., Broomfield, CO, USA) at baseline and 1 week after compression stockings use. The observed results are expressed as median and interquartile range (25,75 percentiles): AIH at baseline: 20.8 (14.2; 39.6) events/hour; AIH after compression stockings use: 16.7 (3.5; 28.9) events/hour | 1 week | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change of Heart Rate Variability Change From Baseline | Electrocardiogram performed during polysomnography examination will be downloaded to a specific software for heart rate variability assessment (Kubius HRV™, University of Eastern Finland, Finland), which provides spectral assessment of heart rate variability in its both components: low frequency (LF) and high frequency (HF). Patients who present higher LF/HF during the night compared to the beggining of the polysomnography exam have, by definition, increased sympathetic activity during the night. Such evaluation will be accessed in both baseline and after compression stockings use. | 1 week | 
| Change in Fluid Distribution From Baseline | Segmental and total body water will be non-invasively assessed before sleeping and after awakening by a bioimpedance device (InBody S10 Analyser™, Biospace, South Korea), which will provide information regarding nighttime fluid shift at baseline and after compression stocking use. The amount of water, expressed in liters, is assessed in both extra and intracellular components. | 1 week | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Hemodialysis, Obstructive sleep apnea, Compression stockings