An interventional study of Descent to sea level in Pulmonary Arterial Hypertension (PAH), Pulmonary Vascular Disease and Polygraphy, sponsored by Silvia Ulrich Somaini. Not yet recruiting at 1 site in Switzerland. Open to participants aged 18 Years to 80 Years. Per ClinicalTrials.gov, last updated 2026-09-03.
Sponsored by Silvia Ulrich Somaini · Not applicable, Interventional, and Supportive care
To study the effect of relocation from high altitude (Quito Ecuador: 2850m) to sea level on sleeping parameters by polygraphy in patients with pulmonary arterial hypertension PAH, who live permanently >2600m.
The aim of this research is to investigate sleeping parameters by polygraphy before and after relocation (high altitude near their living altitude vs. sea level) in patients with diagnosed pulmonary arterial hypertension according to guidelines, who permanently live at high altitude over 2600m
699 studies on the registry are indexed under Pulmonary Arterial Hypertension; 140 are open to participants now.
This study's planned enrollment of 20 is below the median of 40 across 477 interventional studies indexed under Pulmonary Arterial Hypertension.
Browse Pulmonary Arterial Hypertension studies →Silvia Ulrich Somaini is the lead sponsor of 17 studies on the registry; 16 are open to participants now.
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Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
The New York Heart Association’s four classes of how much heart failure limits physical activity.
Studies set their own limit — many outside heart failure leave out class III–IV, while heart failure studies may ask for a particular class. Check the class this study names.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
From a breathing test (spirometry): how much air you can blow out in the first second. Often given as a percentage of what is expected for your age, height and sex.
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
NYHA class (heart failure)
The New York Heart Association’s four classes of how much heart failure limits physical activity.
Studies set their own limit — many outside heart failure leave out class III–IV, while heart failure studies may ask for a particular class. Check the class this study names.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
FEV1
From a breathing test (spirometry): how much air you can blow out in the first second. Often given as a percentage of what is expected for your age, height and sex.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hemoglobin (Hb)
The protein in red blood cells that carries oxygen. A low level is anaemia, which can cause tiredness and breathlessness. Measured in g/dL or g/L (9 g/dL is 90 g/L).
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Assessment of sleep-parameters by polygraphy in patients with pulmonary arterial hypertension at 2850m and at sea level
Behavioral: Descent to sea level
Descent from 2850m to sea level with a stay for 7 days and re-ascent back to 2850m
Mean nocturnal SpO2 after 7 days at sea level
Difference in mean nocturnal SpO2 between 2850m and Night 7 at sea level in patients with pulmonary arterial hypertension
Time frame: From high altitude (2850m) to night 7 at sea level
Time spent with low SpO2 after 7 days at sea level
Difference/change in time spent with low SpO2 (\< 90% and \< 80%) between 2850m and night 7 at sea level in patients with pulmonary arterial hypertension
Time frame: From high altitude (2850m) to night 7 at sea level
Apnoea-Hypopnoea-Index AHI after 7 days at sea level
Difference/change in nocturnal apnoea-hypopnoea-index between 2850m and night 7 at sea level in patients with pulmonary arterial hypertension
Time frame: From high altitude (2850m) to night 7 at sea level
Oxygen-Desaturation-Index ODI after 7 days at sea level
Difference/change in nocturnal Oxygen-Desaturation-Index ODI between 2850m and night 7 at sea level in patients with pulmonary arterial hypertension
Time frame: From high altitude (2850m) to night 7 at sea level
Nocturnal cardiovascular autonomic control after 7 days at sea level
Difference/change in nocturnal cardiovascular autonomic control by heart rate (variability) between 2850m and night 7 at sea level in patients with pulmonary arterial hypertension
Time frame: From high altitude (2850m) to night 7 at sea level
Acclimatization-Effect of mean nocturnal SpO2 at sea level
Difference/change in mean nocturnal SpO2 at night 1 and night 7 within a stay at sea level of 7 days (after relocation from high altitude) in patients with pulmonary arterial hypertension
Time frame: From Night 1 to Night 7 at sea level
Acclimatization-Effect of time spent with low SpO2 at sea level
Difference/change in time spent with low SpO2 (\< 90% and \< 80%) at night 1 and night 7 within a stay at sea level of 7 days (after relocation from high altitude) in patients with pulmonary arterial hypertension
Time frame: From Night 1 to Night 7 at sea level
Acclimatization-Effect of Apnoea-Hypopnoea-Index AHI at sea level
Difference/change in nocturnal apnoea-hypopnoea-index at night 1 and night 7 within a stay at sea level of 7 days (after relocation from high altitude) in patients with pulmonary arterial hypertension
Time frame: From Night 1 to Night 7 at sea level
Acclimatization-Effect of Oxygen-Desaturation-Index ODI at sea level
Difference/change in nocturnal oxygen-desaturation-index ODI at night 1 and night 7 within a stay at sea level of 7 days (after relocation from high altitude) in patients with pulmonary arterial hypertension
Time frame: From Night 1 to Night 7 at sea level
Acclimatization-Effect of nocturnal cardiovascular autonomic control at sea level
Difference/change in nocturnal cardiovascular autonomic control by heart rate (variability) at night 1 and night 7 within a stay at sea level of 7 days (after relocation from high altitude) in patients with pulmonary arterial hypertension
Time frame: From Night 1 to Night 7 at sea level
Mean nocturnal SpO2 after re-ascent to 2850m
Difference/change in mean nocturnal SpO2 between sea level (after one-week stay) and night after re-ascent to 2850m in patients with pulmonary arterial hypertension
Time frame: From Night 7 at sea level to night after reascent (time frame of 3 days)
Time spent with low SpO2 after re-ascent to 2850m
Difference/change in time spent with low SpO2 (\< 90% and \< 80%) between sea level (after one-week stay) and night after re-ascent to 2850m in patients with pulmonary arterial hypertension
Time frame: From Night 7 at sea level to night after re-ascent (time frame of 3 days)
Apnoea-Hypopnoea-Index AHI after re-ascent to 2850m
Difference/change in nocturnal apnoea-hypopnoea-index between sea level (after one-week stay) and night after re-ascent to 2850m in patients with pulmonary arterial hypertension
Time frame: From Night 7 at sea level to night after re-ascent (time frame of 3 days)
Oxygen-Desaturation-Index ODI after re-ascent to 2850m
Difference/change in nocturnal oxygen-desaturation-index between sea level (after one-week stay) and night after re-ascent to 2850m in patients with pulmonary arterial hypertension
Time frame: From Night 7 at sea level to night after re-ascent (time frame of 3 days)
Nocturnal cardiovascular autonomic control after re-ascent to 2850m
Difference/change in nocturnal cardiovascular autonomic control by heart rate (variability) between sea level (after one-week stay) and night after re-ascent to 2850m in patients with pulmonary arterial hypertension
Time frame: From Night 7 at sea level to night after re-ascent (time frame of 3 days)
Mean nocturnal SpO2 pre-descent and after re-ascent (2850m)
Difference/change in mean nocturnal SpO2 between the night at 2850m prior to the descent to sea level (stay of 7 days at sea level in between) and the night at 2850m after re-ascent in patients with pulmonary arterial hypertension
Time frame: From the night at 2850m prior to the descent, stay at sea level of one week in between to the night after re-ascent to 2850m (time frame approximately 11 days)
Time spent with low SpO2 pre-descent and after re-ascent (2850m)
Difference/change in time spent with low SpO2 (\< 90% and \< 80%) between the night at 2850m prior to the descent to sea level (stay of 7 days at sea level in between) and the night at 2850m after re-ascent in patients with pulmonary arterial hypertension
Time frame: From the night at 2850m prior to the descent, stay at sea level of one week in between to the night after re-ascent to 2850m (time frame approximately 11 days)
Apnoea-Hypopnoea-Index AHI pre-descent and after re-ascent (2850m)
Difference/change in nocturnal apnoea-hypopnoea-index between the night at 2850m prior to the descent to sea level (stay of 7 days at sea level in between) and the night at 2850m after re-ascent in patients with pulmonary arterial hypertension
Time frame: From the night at 2850m prior to the descent, stay at sea level of one week in between to the night after re-ascent to 2850m (time frame approximately 11 days)
Oxygen-Desaturation-Index ODI pre-descent and after re-ascent (2850m)
Difference/change in nocturnal oxygen-desaturation-index between the night at 2850m prior to the descent to sea level (stay of 7 days at sea level in between) and the night at 2850m after re-ascent in patients with pulmonary arterial hypertension
Time frame: From the night at 2850m prior to the descent, stay at sea level of one week in between to the night after re-ascent to 2850m (time frame approximately 11 days)
Nocturnal cardiovascular autonomic control pre-descent and after re-ascent (2850m)
Difference/change in nocturnal cardiovascular autonomic control by heart rate (variability) between the night at 2850 prior to the descent to sea level (stay of 7 days at sea level in between) and the night at 2850m after re-ascent in patients with pulmonary arterial hypertension
Time frame: From the night at 2850m prior to the descent, stay at sea level of one week in between to the night after re-ascent to 2850m (time frame approximately 11 days)
Plan to share: Yes — Data will be provided upon request and based on a clear intention reviewed by an ethical review board.
No publications or documents are linked to this record.
Start is estimated for Sep 2026; primary completion for Oct 2026, 0 months later.
Of 60 non-industry interventional studies with no phase under Pulmonary Arterial Hypertension, half reached primary completion within 44 months of starting (the median), counting those still running; a quarter within 18 and three quarters within 63. This study's planned 0 months is below that.
Counting every sponsor, half of 65 studies reached it within 42 months; a quarter within 18 and three quarters within 71.
How these figures are worked out, and which studies are left out of them.
This study is not yet recruiting, as verified in Aug 2026. You cannot join it, but the record below documents what was studied.
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Pulmonary Arterial Hypertension →
Silvia Ulrich Somaini