Sleep-Assessment in Patients Between High Altitude HA vs. Sea Level LA in Patients With Pulmonary Arterial Hypertension PAH

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 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.

Study Overview

• Status: Not yet recruiting
• Conditions: Sleep; High Altitude; Pulmonary Arterial Hypertension (PAH); High Altitude Effects; Pulmonary Vascular Disease; Polygraphy; Sleep Disordered Breathing (SDB)
• Intervention / Treatment: Behavioral: Descent to sea level

Detailed Description

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

• Study Type: Interventional
• Enrollment (Estimated): 20
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Silvia Ulrich, Prof. Dr. med.; Phone Number: +41442552220; Email: silvia.ulrich@usz.ch
• Study Contact Backup: Name: Michael Furian, Prof. Dr. sc. ETH; Phone Number: +41442552220

Study Locations

• Switzerland
  • Zurich, Switzerland, 8091
    • University Hospital of Zurich

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Adult patients aged 18-80 years and of all genders
• Permanent residence > 2600 m
• Diagnosis of pulmonary arterial hypertension PAH (PAHHA-Group) according to guidelines
• Patients are stable on therapy
• NYHA (new york heart association) functional class I-III.
• written informed consent to participate in the study.

Exclusion Criteria:

• Age <18 years or >80 years
• unstable condition
• Patients who cannot follow the study investigations
• Patient permanently living < 2600m.
• Patients who traveled and stayed overnight at altitudes <2000 m in the past 4 weeks.
• Patients with moderate to severe concomitant lung disease (FEV1<70% or forced vital capacity <70%), severe parenchymal lung disease, severe smokers (>20 cigarettes/day)
• Severely hypoxemic patients at Quito permanently having persistent SpO2 (oxygen saturation by pulseoximetry) <80% on ambient air.
• Patient with a non-corrected ventricular septum defect
• Relevant concomitant other disease of the heart, kidney, liver, blood (anemia hemoglobin<11 g/dl)

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Supportive Care
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Sleep-parameters at 2850m and at sea level; 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

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
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	From high altitude (2850m) to night 7 at sea level

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
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	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	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	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	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	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	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	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	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	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	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	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	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	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	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	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	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	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	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	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)

Collaborators and Investigators

• Sponsor: Silvia Ulrich Somaini
• Investigators: Principal Investigator: Silvia Ulrich, University Hospital Zurich, Departement of Pulmonology; Principal Investigator: Rodrigo Hoyos, Hospital Carlos Andrade Marin of Quito, Ecuador

Study record dates

Study Major Dates

• Study Start (Estimated): September 25, 2026
• Primary Completion (Estimated): October 4, 2026
• Study Completion (Estimated): December 31, 2026

Study Registration Dates

• First Submitted: August 17, 2026
• First Submitted That Met QC Criteria: August 31, 2026
• First Posted (Actual): September 3, 2026

Study Record Updates

• Last Update Posted (Actual): September 3, 2026
• Last Update Submitted That Met QC Criteria: August 31, 2026
• Last Verified: August 1, 2026

More Information

Terms related to this study

• Keywords: Pulmonary Hypertension; Sleep; Hypoxia; High Altitude; Pulmonary Arterial Hypertension (PAH); Polygraphy; Pulmonary vascular disease; Sleep disordered breathing SDB
• Additional Relevant MeSH Terms: Nervous System Diseases; Vascular Diseases; Cardiovascular Diseases; Respiratory Tract Diseases; Lung Diseases; Respiration Disorders; Sleep Wake Disorders; Signs and Symptoms, Respiratory; Apnea; Sleep Disorders, Intrinsic; Dyssomnias; Hypertension; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Pulmonary Arterial Hypertension; Hypoxia; Sleep Apnea Syndromes; Hypertension, Pulmonary; Altitude Sickness
• Other Study ID Numbers: Ec_HAvsLA_sleep_PAH

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: Data will be provided upon request and based on a clear intention reviewed by an ethical review board.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No