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Treatment of Patients With the Obstructive Sleep Apnea Syndrome at Altitude

This study has been completed.
Information provided by (Responsible Party):
University of Zurich Identifier:
First received: July 8, 2008
Last updated: May 18, 2014
Last verified: May 2014
The purpose of the study is to investigate the effect of 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

Condition Intervention Phase
Obstructive Sleep Apnea Syndrome Drug: acetazolamide Phase 4

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary Purpose: Treatment
Official Title: Treatment of Patients With the Obstructive Sleep Apnea Syndrome at Altitude

Resource links provided by NLM:

Further study details as provided by University of Zurich:

Primary Outcome Measures:
  • sleep disordered breathing, sleep structure, vigilance, subjective sleep quality acute mountain sickness [ Time Frame: during treatment while at altitude ]

Secondary Outcome Measures:
  • blood pressure endothelial function [ Time Frame: during treatment while at altitude ]

Enrollment: 49
Study Start Date: June 2008
Study Completion Date: December 2008
Primary Completion Date: December 2008 (Final data collection date for primary outcome measure)
Intervention Details:
    Drug: acetazolamide
    acetazolamide 2 times 250mg per day
    Other Name: Diamox

Ages Eligible for Study:   20 Years to 70 Years   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • Obstructive sleep apnea syndrome, successfully on CPAP therapy
  • Residence at low altitude (<800m)
  • 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 or recently diagnosed (within the last 6 months) cardiovascular disease such as arterial hypertension, coronary artery or cerebrovascular 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 (<2600m).
  • Exposure to altitudes >1500m for >1 day within the last 4 weeks before the study
  Contacts and Locations
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Please refer to this study by its identifier: NCT00714740

Pulmonary Division, University Hospital Zurich
Zurich, Switzerland, CH-8091
Sponsors and Collaborators
University of Zurich
Study Director: Konrad E Bloch, MD Pulmonary Division, University Hospital Zurich, Switzerland
  More Information

Responsible Party: University of Zurich Identifier: NCT00714740     History of Changes
Other Study ID Numbers: EK-1522
Study First Received: July 8, 2008
Last Updated: May 18, 2014

Keywords provided by University of Zurich:
apnea, sleep, altitude, hypoxia

Additional relevant MeSH terms:
Sleep Apnea Syndromes
Sleep Apnea, Obstructive
Pathologic Processes
Respiration Disorders
Respiratory Tract Diseases
Signs and Symptoms, Respiratory
Signs and Symptoms
Sleep Disorders, Intrinsic
Sleep Wake Disorders
Nervous System Diseases
Carbonic Anhydrase Inhibitors
Enzyme Inhibitors
Molecular Mechanisms of Pharmacological Action
Natriuretic Agents
Physiological Effects of Drugs processed this record on September 19, 2017