Randomized-controlled Trial (RCT) on CPAP-withdrawal and Microvascular Function in OSA

Study Overview
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Brief Summary
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Randomized controlled trial (therapeutic vs. placebo CPAP) including 46 patients with obstructive sleep apnea (OSA) to define the physiological effects of continuous positive airway pressure (CPAP) therapy withdrawal on myocardial perfusion and dermal and renal microvascular function during a 2 week period.

Official Title
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The Effects of CPAP-withdrawal on Microvascular Function in Patients With Obstructive Sleep Apnea: A Randomized-controlled Trial

Conditions
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Obstructive Sleep Apnoea

Intervention / Treatment
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* Other: CPAP therapy withdrawal
* Procedure: Continue CPAP treatment


Participation Criteria
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Eligibility Criteria
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Inclusion criteria: Objectively confirmed OSA (at the time of original diagnosis) with an oxygen desaturation index (ODI, =4% dips) of >20/h and an ESS of >10. Currently >20/h oxygen desaturations (=4% dips) during an ambulatory nocturnal pulse oximetry performed at the end of a 4-night period without CPAP. Treated with CPAP for more than 12 months, minimum compliance 4h per night, AHI<10 with treatment (according to CPAP machine download data). Current ESS <10. Exclusion criteria: Previous ventilatory failure (awake SpO2 <93% and PaCO2>6kPa). Unstable, untreated coronary or peripheral artery disease, severe arterial hypertension or hypotension (>180/110 or <90/60mmHg) Previously diagnosed with Cheyne-Stokes breathing. Current professional driver; Any previous sleep related accident. Age <20 or >75 years at trial entry. Acute inflammatory disease

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 |
| --- | --- |
| Placebo Comparator: Placebo CPAP<br>patients established on CPAP therapy, who are randomized to the placebo comparator, will use a CPAP device with subtherapeutic pressure during two weeks. | Other: CPAP therapy withdrawal<br>* CPAP (continuous positive airway pressure) with subtherapeutic pressure during two weeks<br>* Other names: CPAP treatment with subtherapeutic pressure;|
| Active Comparator: therapeutic CPAP<br>patients who are randomized to the active comparator, will continue with CPAP treatment with therapeutic pressure during two weeks | Procedure: Continue CPAP treatment<br>* Continue treatment with therapeutic continuous positive airway pressure device<br>* Other names: therapeutic continuous positive airway pressure device;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| hyperaemic myocardial blood flow |  | 2 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Coronary flow reserve | Coronary flow reserve determined by PET | 2 weeks | 
| Urine albumine excretion rate |  | 2 weeks | 
| Dermal microvascular vasodilatory response |  | 2 weeks |