Continuous Positive Airway Pressure and Acetazolamide to Treat Sleep Apnea Syndrome Patients at Altitude

Study Overview
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Brief Summary
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The purpose of the study is to investigate the effect of nasal continuous positive airway pressure in combination with acetazolamide as a treatment for sleep related breathing disturbances in patients with the obstructive sleep apnea syndrome living at low altitude during a sojourn at moderate altitude.

Official Title
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Continuous Positive Airway Pressure (CPAP) and Acetazolamide for Treatment of Patients With the Obstructive Sleep Apnea Syndrome at Altitude

Conditions
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Obstructive Sleep Apnea Syndrome

Intervention / Treatment
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* Drug: acetazolamide
* Procedure: nocturnal continuous positive airway pressure
* Drug: placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Obstructive sleep apnea syndrome, successfully on CPAP therapy Residence at low altitude (< 800 m) Obstructive apnea/hypopnea index >20/h and a complaint of excessive daytime sleepiness before introduction of CPAP therapy > 15 oxygen desaturations/h (> 3% dips) during an ambulatory nocturnal pulse oximetry performed at the end of a 4-night period without CPAP Exclusion Criteria: Sleep disorders other than OSA More than mild cardiovascular disease, unstable cardiovascular disease Any lung disease, pulmonary hypertension Chronic rhinitis Treatment with drugs that affect respiratory center drive (benzodiazepines or other sedatives or sleep inducing drugs, morphine or codeine derivates), stimulants (modafinil, methylphenidate, theophylline) Internal, neurologic or psychiatric disease that interfere with sleep quality Previous intolerance to moderate or low altitude (< 2600 m) Exposure to altitudes > 1500m for > 1 day within the last 4 weeks before the study

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 80 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: Crossover Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: acetazolamide<br>combination of acetazolamide and nocturnal continuous positive airway pressure ventilation | Drug: acetazolamide<br>* acetazolamide 250mg 1/0/2<br>* Other names: Diamox (trade name);Procedure: nocturnal continuous positive airway pressure<br>* continuous positive airway pressure<br>* Other names: placebo capsules;|
| Placebo Comparator: placebo capsules<br>combination of placebo and nocturnal continuous positive airway pressure ventilation | Procedure: nocturnal continuous positive airway pressure<br>* continuous positive airway pressure<br>* Other names: placebo capsules;Drug: placebo<br>* placebo capsules<br>* Other names: placebo capsules;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| sleep disordered breathing and oxygenation |  | day 2 and 3 at altitude | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| sleep quality, vigilance, acute mountain sickness, blood pressure |  | day 2 and 3 at altitude | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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apnea, sleep, altitude, hypoxia, treatment, CPAP