The Effect of Continuous Positive Airway Pressure on Diastolic Function in Patients With Obstructive Sleep Apnea

Study Overview
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Brief Summary
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The association of obstructive sleep apnea (OSA) and cardiac diastolic dysfunction have been reported, and improvement of diastolic function after continuous positive airway pressure (CPAP) in OSA patients was observed. However, more detailed analysis of diastolic function by supine bicycle exercise echocardiography is lacking. The investigators hypothesized that 3 months of CPAP therapy in OSA patients will significantly improve diastolic functional parameters measured by exercise stress echocardiography. Patients with severe OSA (Apnea-hypopnea index > 30) will be included in this study, and randomized to CPAP versus sham-CPAP group by 1:1 ratio. Supine bicycle exercise echocardiography, pulse wave velocity, 24 hours ambulatory blood pressure (BP), central BP will be checked before and after CPAP therapy and parameters will be compared.

Conditions
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Obstructive Sleep Apnea

Intervention / Treatment
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* Device: CPAP group
* Device: sham-CPAP group


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patietns≥20 and ≤75 years-old Patients who diagnosed as obstructive sleep apnea and AHI>30 on polysomnography Exclusion Criteria: Age < 20 years-old Left ventricular dysfunction (LVEF<50%) or structural heart disease on transthoracic echocardiography Diabetes mellitus Significant cardiac valvular disease (≥moderate) Severe hypertension (>180/110mmHg) Moderate or severe kidney disease (eGFR < 60 mL/min ) Clinically significant liver disease History of coronary artery disease malignancy or autoimmune disease Acute/chronic infection status Pregnant status Patients taking anxiolytics or sedatives

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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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: CPAP group<br> | Device: CPAP group<br>* Enrolled patients are randomized to CPAP group or sham-CPAP group by 1:1 ratio. The patients in each group will undergo CPAP or sham-CPAP for 3 months.<br>|
| Sham Comparator: sham-CPAP group<br> | Device: sham-CPAP group<br>* Enrolled patients are randomized to CPAP group or sham-CPAP group by 1:1 ratio. The patients in each group will undergo CPAP or sham-CPAP for 3 months. Sham CPAP consists of a CPAP machine that is modified to include a large hidden leak in the exhaust port of the mask to disperse the therapeutic pressure.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The differences of supine bicycle exercise echocardiographic parameters and PWV before and after CPAP therapy, and between CPAP group and sham CPAP group. | The differences of supine bicycle exercise echocardiogrphic parameters (diastolic function grade, mitral inflow parameters, mitral tissue doppler parameters, E/E') and PWV before and after CPAP therapy, and between CPAP group and sham CPAP group. | after 3 months intervention (CPAP) | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Obstructive sleep apnea, Continuous positive airway pressure, diastolic function