High AltitudeNCT07797088
Assessment of Six-minute Walking Distance Between Sea Level LA vs. High Altitude HA After Re-ascent in Healthy Individuals
A study testing Re-Ascent sea level to 2850m in people with High Altitude and Healthy, run by Silvia Ulrich Somaini at 1 site in Switzerland.
Trial summary
To study the effect of a re-ascent after a one-week stay at sea level (after prior descent from 2850m) to high altitude (Quito Ecuador: 2850m) on six-minute walking distance and other scores in healthy individuals, who live permanently >2600m. Read more about this study
- Who is it for?
- Ages 18 to 80 yearsHealthy volunteers can take part
- Conditions the study is for
- High Altitude, Healthy, Healthy Adult
- What is being tested?
- Re-Ascent sea level to 2850m
- Type of treatment
- Lifestyle or therapy programme
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 14 participants
- Where
- 1 siteSwitzerland
- Study dates
- 25 Sep 2026to 31 Dec 2026
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 80 years
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Who may be able to join
- Adults aged 18-80 years and of all genders
- Permanent residence > 2600 m
- healthy: no self-perceived cardiopulmonary disease limiting daily activities
- written informed consent to participate in the study.
Who cannot join
- Age <18 years or >80 years
- Participants who cannot follow the study investigations
- Participants permanently living < 2600m
- Participants who traveled and stayed overnight at altitudes <2000 m in the past 4 weeks.
- any self-perceived cardiopulmonary disease limiting daily activities
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Michael Furian, Prof. Dr. sc. ETH contact
About this study
Official title: Effect of a One-week Descent From 2850m to Sea Level and Re-ascent in Patients With Pulmonary Arterial Hypertension and Healthy Controls Permanently Living > 2600m on Pulmonary Hemodynamics, Exercise Capacity, Blood Oxygenation, Sleep Disordered Breathing and Further Outcomes
To study the effect of a re-ascent after a one-week stay at sea level (after prior descent from 2850m) to high altitude (Quito Ecuador: 2850m) on six-minute walking distance and other scores in healthy individuals, who live permanently >2600m.
Read the detailed description
The aim of this research is to investigate the six-minute walking distance and other scores before and after re-ascent (sea level for 7 days vs. re-ascent to 2850m) in healthy individuals, who permanently live at high altitude over 2600m.
- Being tested
- Re-Ascent sea level to 2850m
- Keywords
- hypoxia, high altitude, six-minute walking distance, Health, NYHA, Exercise testing
- Medical subject headings
- Altitude Sickness, Hypoxia
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Re-Ascent sea level to 2850mBehavioural
After 7 days at sea level return/re-ascent to their usual living altitude at 2850m
| Study group | Role | What they receive |
|---|---|---|
| SIx-minute walking distance 6MWD after re-ascent at 2850m | Experimental | Assessment of six-minute walking distance 6MWD and other scores after 7 days at sea level with re-ascent from sea level back to 2850m by bus (in one day) and assessments of the same outcomes Receives: Behavioral: Re-Ascent sea level to 2850m |
What is being measured
The primary outcome is the main question the study is designed to answer.
Six-minute walking distance after re-ascent to 2850m
Difference/change in six-minute walking distance 6MWD between sea level (after one-week stay) and day after re-ascent at 2850m in healthy individuals
Measured: From Day 5-7 at sea level to the day after re-ascent
Secondary outcomes (15)
SpO2 at rest and end-exercise after re-ascent to 2850m
Difference/change in SpO2 (peripheral oxygen saturation) at rest and end-exercise between sea level (after one-week stay) and Day after re-ascent to 2850m in healthy individuals
Measured: From Day 5-7 at sea level to the day after re-ascent
Heart rate at rest and end-exercise after re-ascent to 2850m
Difference/change in heart rate at rest and end-exercise between sea level (after one-week stay) and Day after re-ascent to 2850m in healthy individuals
Measured: From Day 5-7 at sea level to the day after re-ascent
Blood pressure at rest and end-exercise after re-ascent to 2850m
Difference/change in blood pressure at rest and end-exercise between sea level (after one-week stay) and Day after re-ascent to 2850m in healthy individuals
Measured: From Day 5-7 at sea level to the day after re-ascent
Dyspnea and leg discomfort sensation after re-ascent to 2850m
Difference/change in dyspnea and leg discomfort sensation (assessed with BORG-CR10-Scale, Category Rating 0-10 with 10 being the most dyspnea/leg discomfort) at rest and end-exercise between sea level (after one-week stay) and day after re-ascent to 2850m in healthy individuals
Measured: From Day 5-7 at sea level to the day after re-ascent
NYHA functional class after re-ascent to 2850m
Difference/change in NYHA functional class (New York Heart Association Class I-IV, IV being the worst) at rest and end-exercise between sea level (after one-week stay) and day after re-ascent to 2850m in healthy individuals
Measured: From Day 5-7 at sea level to the day after re-ascent
Quality of life after re-ascent to 2850m
Difference/change in quality of life score (EmPHasis-10: Score with 10 questions and 0-50 points, higher scores indicating poorer quality of life) between sea level (after one-week stay) and day after re-ascent to 2850m in healthy individuals
Measured: From Day 5-7 at sea level to the day after re-ascent
General well-being after re-ascent to 2850m
Difference/change in general well-being (Visual Analog Scale 10cm: the higher, the worse) between sea level (after one-week stay) and day after re-ascent to 2850m in healthy individuals
Measured: From Day 5-7 at sea level to the day after re-ascent
Six-minute walking test pre-descent to after re-ascent
Difference/change in six-minute walking distance (6MWD) at 2850m with a one-week stay at sea level in between (day pre-descent vs. day after re-ascent) in healthy individuals
Measured: Baseline at 2850m followed by a one-week stay at sea level to the day after re-ascent back to 2850m (time frame approximately 11 days)
SpO2 at rest and end-exercise pre-descent to after re-ascent
Difference/change in SpO2 (peripheral oxygen saturation) at rest and end-exercise with a one-week stay at sea level in between (day pre-descent vs. day after re-ascent) in healthy individuals
Measured: Baseline at 2850m followed by a one-week stay at sea level to the day after re-ascent back to 2850m (time frame approximately 11 days)
Heart rate at rest and end-exercise pre-descent to after re-ascent
Difference/change in heart rate at rest and end-exercise with a one-week stay at sea level in between (day pre-descent vs. day after re-ascent) in healthy individuals
Measured: Baseline at 2850m followed by a one-week stay at sea level to the day after re-ascent back to 2850m (time frame approximately 11 days)
Blood pressure at rest and end-exercise pre-descent to after re-ascent
Difference/change in blood pressure at rest and end-exercise with a one-week stay at sea level in between (day pre-descent vs. day after re-ascent) in healthy individuals
Measured: Baseline at 2850m followed by a one-week stay at sea level to the day after re-ascent back to 2850m (time frame approximately 11 days)
Dyspnea and leg discomfort pre-descent to after re-ascent
Difference/change in dyspnea and leg discomfort (assessed with BORG-CR10-Scale, Category Rating 0-10 with 10 being the most dyspnea/leg discomfort) at rest and end-exercise with a one-week stay at sea level in between (day pre-descent vs. day after re-ascent) in healthy individuals
Measured: Baseline at 2850m followed by a one-week stay at sea level to the day after re-ascent back to 2850m (time frame approximately 11 days)
NYHA functional class pre-descent to after re-ascent
Difference/change in NYHA functional class (New York Heart Association Class I-IV, IV being the worst) at 2850m with a one-week stay at sea level in between (day pre-descent vs. day after re-ascent) in healthy individuals
Measured: Baseline at 2850m followed by a one-week stay at sea level to the day after re-ascent back to 2850m (time frame approximately 11 days)
Quality of life pre-descent to after re-ascent
Difference/change in quality of life (EmPHasis-10: Score with 10 questions and 0-50 points, higher scores indicating poorer quality of life) with a one-week stay at sea level in between (day pre-descent vs. day after re-ascent) in healthy individuals
Measured: Baseline at 2850m followed by a one-week stay at sea level to the day after re-ascent back to 2850m (time frame approximately 11 days)
General well-being pre-descent to after re-ascent
Difference/change in general well-being (Visual Analog Scale 10cm: the higher, the worse) with a one-week stay at sea level in between (day pre-descent vs. day after re-ascent) in healthy individuals
Measured: Baseline at 2850m followed by a one-week stay at sea level to the day after re-ascent back to 2850m (time frame approximately 11 days)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted1 Sep 2026
- Study start25 Sep 2026 (estimated)
- Primary completion4 Oct 2026 (estimated)
- Study completion31 Dec 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for High AltitudeStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Supportive care
- Allocation
- Not applicable
- Intervention model
- Single group
- Model description
- Healthy individuals living permanently \> 2600m around Quito (Ecuador) will be assessed after 7 days at sea level and after re-ascent to 2850m
- Masking
- None (open label)
- Enrolment
- 14 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Silvia Ulrich Somaini
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor-investigator, Silvia Ulrich Somaini, University of Zurich
- Investigators
- Silvia Ulrich, Principal investigator, University Hospital Zurich, Departement of PulmonologyRodrigo Hoyos, Principal investigator, Hospital Carlos Andrade Marin of Quito, Ecuador
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07797088
- Sponsor's protocol ID
- Ec_LAvsHA_6MWD_H
- Status last verified
- Aug 2026
- First submitted
- 17 Aug 2026
- Last updated
- 1 Sep 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Yes: Data will be provided upon request and based on a clear intention reviewed by an ethical review board.
Study at a glance
From the registry record, last updated by the sponsor on 1 Sep 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Effect of a One-week Descent From 2850m to Sea Level and Re-ascent in Patients With Pulmonary Arterial Hypertension and Healthy Controls Permanently Living > 2600m on Pulmonary Hemodynamics, Exercise Capacity, Blood Oxygenation, Sleep Disordered Breathing and Further Outcomes
- ClinicalTrials.gov ID
- NCT07797088
- Acronym / sponsor ID
- Ec_LAvsHA_6MWD_H
- Keywords
- hypoxia, high altitude, six-minute walking distance, Health, NYHA, Exercise testing
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 14 participants (estimated)
- Lead sponsor
- Silvia Ulrich SomainiUniversity, hospital or other
- Study start
- 25 Sep 2026 (estimated)
- Primary completion
- 4 Oct 2026 (estimated)
- Study completion
- 31 Dec 2026 (estimated)
- First posted
- 1 Sep 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
To study the effect of a re-ascent after a one-week stay at sea level (after prior descent from 2850m) to high altitude (Quito Ecuador: 2850m) on six-minute walking distance and other scores in healthy individuals, who live permanently >2600m.
Detailed description
The aim of this research is to investigate the six-minute walking distance and other scores before and after re-ascent (sea level for 7 days vs. re-ascent to 2850m) in healthy individuals, who permanently live at high altitude over 2600m.
Study design
- Primary purpose
- Supportive care
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
- Model description
- Healthy individuals living permanently > 2600m around Quito (Ecuador) will be assessed after 7 days at sea level and after re-ascent to 2850m
| Arm | Type | Receives |
|---|---|---|
| SIx-minute walking distance 6MWD after re-ascent at 2850m | Experimental | Behavioral: Re-Ascent sea level to 2850mAssessment of six-minute walking distance 6MWD and other scores after 7 days at sea level with re-ascent from sea level back to 2850m by bus (in one day) and assessments of the same outcomes |
Who may qualify
- Ages
- 18 to 80 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (4 listed)
- Adults aged 18-80 years and of all genders
- Permanent residence > 2600 m
- healthy: no self-perceived cardiopulmonary disease limiting daily activities
- written informed consent to participate in the study.
Key exclusion criteria (5 listed)
- Age <18 years or >80 years
- Participants who cannot follow the study investigations
- Participants permanently living < 2600m
- Participants who traveled and stayed overnight at altitudes <2000 m in the past 4 weeks.
- any self-perceived cardiopulmonary disease limiting daily activities
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Re-Ascent sea level to 2850mAfter 7 days at sea level return/re-ascent to their usual living altitude at 2850m | Behavioural | SIx-minute walking distance 6MWD after re-ascent at 2850m |
Primary outcome
Six-minute walking distance after re-ascent to 2850m
Time frame: From Day 5-7 at sea level to the day after re-ascent
Difference/change in six-minute walking distance 6MWD between sea level (after one-week stay) and day after re-ascent at 2850m in healthy individuals
15 secondary outcomes
SpO2 at rest and end-exercise after re-ascent to 2850m
Time frame: From Day 5-7 at sea level to the day after re-ascent
Heart rate at rest and end-exercise after re-ascent to 2850m
Time frame: From Day 5-7 at sea level to the day after re-ascent
Blood pressure at rest and end-exercise after re-ascent to 2850m
Time frame: From Day 5-7 at sea level to the day after re-ascent
Dyspnea and leg discomfort sensation after re-ascent to 2850m
Time frame: From Day 5-7 at sea level to the day after re-ascent
NYHA functional class after re-ascent to 2850m
Time frame: From Day 5-7 at sea level to the day after re-ascent
Quality of life after re-ascent to 2850m
Time frame: From Day 5-7 at sea level to the day after re-ascent
General well-being after re-ascent to 2850m
Time frame: From Day 5-7 at sea level to the day after re-ascent
Six-minute walking test pre-descent to after re-ascent
Time frame: Baseline at 2850m followed by a one-week stay at sea level to the day after re-ascent back to 2850m (time frame approximately 11 days)
SpO2 at rest and end-exercise pre-descent to after re-ascent
Time frame: Baseline at 2850m followed by a one-week stay at sea level to the day after re-ascent back to 2850m (time frame approximately 11 days)
Heart rate at rest and end-exercise pre-descent to after re-ascent
Time frame: Baseline at 2850m followed by a one-week stay at sea level to the day after re-ascent back to 2850m (time frame approximately 11 days)
Blood pressure at rest and end-exercise pre-descent to after re-ascent
Time frame: Baseline at 2850m followed by a one-week stay at sea level to the day after re-ascent back to 2850m (time frame approximately 11 days)
Dyspnea and leg discomfort pre-descent to after re-ascent
Time frame: Baseline at 2850m followed by a one-week stay at sea level to the day after re-ascent back to 2850m (time frame approximately 11 days)
NYHA functional class pre-descent to after re-ascent
Time frame: Baseline at 2850m followed by a one-week stay at sea level to the day after re-ascent back to 2850m (time frame approximately 11 days)
Quality of life pre-descent to after re-ascent
Time frame: Baseline at 2850m followed by a one-week stay at sea level to the day after re-ascent back to 2850m (time frame approximately 11 days)
General well-being pre-descent to after re-ascent
Time frame: Baseline at 2850m followed by a one-week stay at sea level to the day after re-ascent back to 2850m (time frame approximately 11 days)
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 1 Sep 2026.
- Individual participant dataSharing planned: Yes. Data will be provided upon request and based on a clear intention reviewed by an ethical review board.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Michael Furian, Prof. Dr. sc. ETH contact
Silvia Ulrich principal investigator
University Hospital Zurich, Departement of Pulmonology
Rodrigo Hoyos principal investigator
Hospital Carlos Andrade Marin of Quito, Ecuador
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Re-Ascent sea level to 2850m in people with High Altitude and Healthy, run by Silvia Ulrich Somaini at 1 site in Switzerland.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 4 inclusion and 5 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: opening soon, as of the sponsor's last update on 1 Sep 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Switzerland. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Silvia Ulrich, Prof. Dr. med. (+41442552220, silvia.ulrich@usz.ch), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Six-minute walking distance after re-ascent to 2850m (time frame: From Day 5-7 at sea level to the day after re-ascent). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 1 Sep 2026.