Altitude Hypoxia
Conditions
Keywords
healthy participants older than 40 years, postural control, prevention, acetazolamide
Brief summary
Randomized, placebo controlled trial evaluating the effect of acetazolamide on postural control in lowlanders older than 40 years travelling from 760 m to 3'100 m.
Detailed description
This is a randomized, placebo-controlled, double-blind parallel trial evaluating the effect of preventive acetazolamide intake on the postural control in lowlanders older than 40 years travelling to altitude. Participants living in the Bishkek area, Kyrgyzstan (760m), will be transferred by car within 4h to the Tuja Ashu high altitude clinic (3'100 m), and stay there for 2 days. Acetazolamide 375mg/day (or placebo), will be administered before departure at 760 m and during the stay at altitude. Outcomes will be assessed during the stay at 3'100 m. An interim analysis will be carried out when 80 participants will have completed the study or after the first year. The Peto's method will be used and the trial will be stopped when pre-specified futility boundaries were crossed.
Interventions
Administration of 1x125mg acetazolamide in the morning, 2x125mg in the evening, starting 24 hours before departure to 3'100m
Administration of equally looking placebo capsules in the morning and evening, starting 24 hours before departure to 3'100m
Sponsors
Study design
Eligibility
Inclusion criteria
* Healthy men and women, age 40-75 yrs, without any disease and need of medication. * Born, raised and currently living at low altitude (\<800m). * Written informed consent. * Kyrgyz ethnicity
Exclusion criteria
* Any active respiratory, cardiovascular or other disease requiring regular treatment or being otherwise relevant for tolerance of hypoxia or altitude exposure. * Any condition that may interfere with protocol compliance including current heavy smoking (\>20 cigarettes per day or \>20 pack-years with active smoking during the last 10 years), regular use of alcohol. * Allergy to acetazolamide and other sulfonamides.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in anterio-posterior sway velocity (AP) | Day 2 at 760m and 3'100m | Difference in altitude-induced change (between day 2 at 760 meters a.s.l. vs. day 2 at 3'100 meters a.s.l.) of AP sway velocity between acetazolamide and placebo group, measured by a balance platform |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change in arterial oxygen saturation | Day 2 at 760m and 3'100m | Difference in altitude-induced change (between day 2 at 760 meters a.s.l. vs. day 2 at 3'100 meters a.s.l.) of arterial oxygen saturation between acetazolamide and placebo group, measured by pulse oximetry |
| Acute mountain sickness, severity | Day 2 at 3'100m | Difference in acute mountain sickness severity on day 2 at 3'100 meters a.s.l. between acetazolamide and placebo group. |
| Change in cerebral tissue oxygenation | Day 2 at 760m and 3'100m | Difference in altitude-induced change (between day 2 at 760 meters a.s.l. vs. day 2 at 3'100 meters a.s.l.) of cerebral tissue oxygenation between acetazolamide and placebo group, measured by near-infrared spectroscopy. |
| Change in muscle tissue oxygenation | Day 2 at 760m and 3'100m | Difference in altitude-induced change (between day 2 at 760 meters a.s.l. vs. day 2 at 3'100 meters a.s.l.) of muscle tissue oxygenation between acetazolamide and placebo group, measured by near-infrared spectroscopy. |
| AP sway velocity with and without study medication | Day 3 at 760m | Difference in AP sway velocity between acetazolamide and placebo group at 760 m. |
Countries
Kyrgyzstan