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Completed

NCT Number: NCT06498531

HighCycle Study: Effect of Acetazolamide on Sleep Disordered Breathing in Women Compared to Men

Randomized clinical trial evaluating the effect of acetazolamide on sleep disordered breathing in women compared to men travelling to 3600 m.

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Key information

Conditions

Sleep-Disordered Breathing Apnea Dyssomnias Hypoxia Nervous System Diseases Pathological Conditions, Signs and Symptoms Respiration Disorders Respiratory Tract Diseases Signs and Symptoms Signs and Symptoms, Respiratory Sleep Apnea Syndromes Sleep Disorders, Intrinsic Sleep Wake Disorders

Age range

18 year–44 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Phase 4

Primary location

National Center for Cardiology and Internal Medicine

Bishkek, 720040, Kyrgyzstan

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Healthy, non-smoking men and women, age 18-44 years, without any diseases and need of regular medication (including oral contraceptives).
  • BMI >18 kg/m2 and <30 kg/m2
  • Born, raised and currently living at altitudes <1000 m
  • Written informed consent
  • Premenopausal women with an eumenorrheic cycle

Exclusion criteria

  • Other types of contraceptvies (hormonal intrauterine device, vaginal ring, subcutaneous injections or implants, among others)
  • Pregnancy or nursing
  • Anaemic (haemoglobin concentration <10g/dl)
  • Any altitude trip <4 weks before the study
  • Allergy to acetazolamide and other sulfonamides

Treatment and study plan

Acetazolamide

Drug

Administration of 1x125mg acetazolamide in the morning, 1x125mg in the evening, starting 24 hours before departure to 3600 m.

Placebo

Drug

Administration of equally looking placebo capsules in the morning and in the evening, starting 24 hours before departure to 3600 m.

Primary outcomes

  1. Nocturnal oxygen desaturation index (ODI)

    Time frame: Night 1 at 760 m and Night 1 at 3600 m

    Sex-related difference in the altitude-induced change in the ODI (number of ∆SpO2 >3% per hour time in bed measured by pulse oximetry) between acetazolamide and placebo group.

Secondary outcomes

  1. Nocturnal oxygen saturation (SpO2)

    Time frame: Night 1 at 760 m and Night 1 at 3600 m

    Sex-related difference in the altitude-induced change in the mean nocturnal oxygen saturation measured by pulse oximetry between acetazolamide and placebo group.

  2. Nocturnal oxygen saturation (SpO2)

    Time frame: Night 1 at 760 m and Night 2 at 3600 m

    Sex-related difference in the altitude-induced change in the mean nocturnal oxygen saturation measured by pulse oximetry between acetazolamide and placebo group.

  3. Apnea/hypopnea index (AHI)

    Time frame: Night 1 at 760 m and Night 1 at 3600 m

    Sex-related difference in the altitude-induced change in the mean number of apneas/hypopneas per hour between the acetazolamide and placebo group.

  4. Apnea/hypopnea index (AHI)

    Time frame: Night 1 at 760 m and Night 2 at 3600 m

    Sex-related difference in the altitude-induced change in the mean number of apneas/hypopneas per hour between the acetazolamide and placebo group.

  5. Subjective sleep quality

    Time frame: Night 1 at 760 m and Night 1 at 3600 m

    Sex-related difference in the altitude-induced change in subjective sleep quality assessed by a 100-mm visual analog scale between the acetazolamide and placebo group.

  6. Subjective sleep quality

    Time frame: Night 1 at 760 m and Night 2 at 3600 m

    Sex-related difference in the altitude-induced change in subjective sleep quality assessed by a 100-mm visual analog scale between the acetazolamide and placebo group.

  7. Nocturnal oxygen desaturation index (ODI)

    Time frame: Night 1 at 760 m and Night 2 at 3600 m

    Sex-related difference in the altitude-induced change in the ODI (number of ∆SpO2 >3% per hour time in bed measured by pulse oximetry) between acetazolamide and placebo group.

Sponsors and collaborators

Lead sponsor

University of Zurich

Other

Collaborators

  • Laboratoire des Adaptations Métaboliques à l'Exercice en conditions Physiologiques et Pathologiques
  • National Center of Cardiology and Internal Medicine named after academician M.Mirrakhimov
  • University Hospital Heidelberg

Registry information

Official study title

HighCycle Study: Effect of Acetazolamide on Sleep Disordered Breathing in Women. A Randomized, Placebo-Controlled, Double-Blind Parallel Trial.

Important dates

Study start
2024
Primary completion
2025
Study completion
2025
First posted
Jul 12, 2024
Registry last updated
Jun 5, 2026

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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