Healthy
Conditions
Brief summary
The purpose of this study is to investigate the effect of short-term descent in healthy residents at moderate altitude (\>1000 m.a.s.l.).
Detailed description
Polysomnographies will be done for each participant for 2 consecutive nights at the sleep laboratory in Chur (CH; 590 m.a.s.l.) as well as for 2 consecutive nights at the participants home elevations (CH; \>1000 m.a.s.l.). Between the measurements at those two different altitudes there will be a two-week washout period at \>1000 m.a.s.l.. The sequence of altitude exposure will be randomized.
Interventions
DIAGNOSTIC_TESTDescent to low altitude
The polysomnographic recordings include electroencephalogram (EEG), electrooculogram (EOG), electromyogram (EMG), electrocardiogram (ECG), pulse oximetry, transcutaneous capnography, nasal airflow and thoracic and abdominal respiratory effort.
Sponsors
Tsogyal Latshang
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
DIAGNOSTIC
Masking
SINGLE (Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
18 Years to 70 Years
Healthy volunteers
Yes
Inclusion criteria
* Healthy (no current medical condition or intake of regular medication, except negligible medical issues or accidents not interfering with the current health status or physical performance.) * Living above 1000 m.a.s.l. since at least 1 year * No overnight stay at altitudes \<1000 m.a.s.l. in the previous 4 weeks * 18-70 years old * Body mass index 18,5-30 kg/m2 * informed consent
Exclusion criteria
* Active diseases or health related conditions that require treatment (sleep disorders (mainly sleep apnea), chronic rhinitis, cardiovascular and lung diseases) * Use of drugs that affect the respiratory center drive (sedatives, sleep inducing drugs, opioids), stimulants or illegal drugs * Regular consumption of recreational drugs (alcohol and nicotine included)
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| T90 (time spent in SpO2 below 90%) | 4 nights | T90 is the percent of sleeping time which the participant spent in SpO2 below 90%. It provides information about the duration and degree of hypoxia during the whole sleep. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| SpO2 (oxygen saturation) | 4 nights | SpO2 is the amount of haemoglobin bound to oxygen. Normal values lie above 95%. Values below 90% are considered as low and require treatment. |
| AHI (apnea-hypopnea index) | 4 nights | AHI is defined as the number of apneas and hypopneas per hour of sleep, whereby apnea is defined as a cessation of the airflow for ≥10 seconds, while hypopnea is defined as a reduction of the airflow ≥30% with an oxygen desaturation ≥3% or an arousal. |
| SWS (slow-wave sleep) | 4 nights | SWS includes the deep sleep phase. Deep sleep is amongst other important for energy restoration, immune system strengthening and regeneration of cells. |
| AI (arousal index) | 4 nights | AI is the number of arousals per hour of sleep, whereby an arousal is an interruption of sleep from 3-15 seconds. They prevent suffocation in the sleep apnea by interrupting breathing pauses but are also coupled with a lot of stress for the human body. |
| TcCO2 (partial pressure of carbon dioxide) | 4 nights | TcCO2 correlates with PaCO2 and is therefore a non-invasive alternative. A normal value of PCO2 lies between 35 and 45 mmHg. Lower values can lead to muscle cramps, abnormal heartbeat and much more. |
| WASO (wakefulness after sleep onset) | 4 nights | WASO is the time spent awake after sleep onset. High values of WASO are for example found in sleep apnea, insomnia and restless leg syndrome. |
| ODI (oxygen desaturation index) | 4 nights | ODI is defined as the number of oxygen decreases ≥3% per hour of sleep. |
Countries
Switzerland
Contacts
PRINCIPAL_INVESTIGATORTsogyal Latshang, PD Dr. med.
Kantonsspital Graubünden
Outcome results
None listed