High Altitude Residents With High Altitude Pulmonary Hypertension (HAPH), SDB Assessed at HA (3200 m) vs LA (760 m)

Comparative Study of Sleep Disordered Breathing (SDB) in Patients With High Altitude Pulmonary Hypertension Permanently Residing Above 2500 Meters When Assessed Near Resident High Altitude (HA) at 3200 m vs. at Low Altitude (LA) 760 m

To study the effect of relocation from 3200m (Aksay) to 760m (Bishkek) in highlanders with High Altitude Pulmonary Hypertension (HAPH) who permanently live >2500m on sleep disordered breathing

Study Overview

• Status: Completed
• Conditions: High Altitude Pulmonary Hypertension
• Intervention / Treatment: Other: SDB assessment

Detailed Description

This research in highlanders with HAPH diagnosed by echocardiography and defined by a RV/RA >30 mmHg who permanently live at HA >2500 m will have nocturnal respiratory sleep studies near their living altitude in Aksay at 3200 m and on night 1 and 6 at 760m after relocation.

• Study Type: Interventional
• Enrollment (Actual): 24
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Kyrgyzstan
  • Aksay Plateau, Naryn, Kyrgyzstan, Kyrgyzstan
    • Aksay Medical Center

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Permanently living >2500 m
• HAPH diagnosed with a minimum RV/RA of 30 mmHg assessed by echocardiography at an altitude of 3200 m
• Written informed consent

Exclusion Criteria:

• Highlanders who cannot follow the study investigations,
• Patients with moderate to severe concomitant lung disease (FEV1<70% or forced vital capacity <70%), severe parenchymal lung disease, heavy smoking >20 cigarettes/day or >20 pack-years.
• Coexistent unstable systemic hypertension or coronary artery disease that required adjustment of medication within the last 2 months
• Regular use of medication that affects control of breathing (benzodiazepines, opioids, acetazolamide)

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: Assessments at 3200 m and 760 m, respectively; Participants will have a SDB assessment near their resident altitude at 3200 m and after relocation to 760 m after 1 and 7 days	Other: SDB assessment; SDB will be assessed by respiratory polygraphy according to clinical standards

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Mean nocturnal SpO2 during the first night at LA vs HA	Change in mean nocturnal SpO2 (%) between LA (760 m) vs HA (3200 m)	night 1 at 760 m compared to 3200 m.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Mean nocturnal SpO2 during the sixth night at LA vs HA	Change in mean nocturnal SpO2 (%) between LA (760 m) vs HA (3200 m)	night 6 at 760 m compared to 3200 m.
Time spent with SpO2<90% at LA vs HA	Change in time spent with SpO2<90% between LA (760 m) vs HA (3200 m)	night 1 and night 6 at 760 m compared to 3200 m.
AHI at LA vs HA	Change in apnea-hypopnea index (AHI) between LA (760 m) vs HA (3200 m)	night 1 and night 6 at 760 m compared to 3200 m.
ODI at LA vs. HA	Change in oxygen desaturation index (ODI) between LA (760 m) vs HA (3200 m)	night 1 and night 6 at 760 m compared to 3200 m.
Time spent with periodic breathing at LA vs. HA	Change in time spent with periodic breathingbetween LA (760 m) vs HA (3200 m)	night 1 and night 6 at 760 m compared to 3200 m.
Heart rate variability at LA vs. HA	Change in heart rate variability between LA (760 m) vs HA (3200 m)	night 1 and night 6 at 760 m compared to 3200 m.
ECG markers of repolarization at LA vs. HA	Change in electrocardiogram (ECG) markers of repolarization (QT time) between LA (760 m) vs HA (3200 m)	night 1 and night 6 at 760 m compared to 3200 m.
pulse transit time drops at LA vs. HA	Change in pulse transit time drops between LA (760 m) vs HA (3200 m)	night 1 and night 6 at 760 m compared to 3200 m.

Collaborators and Investigators

• Sponsor: University of Zurich
• Investigators: Principal Investigator: Silvia Ulrich, Prof. Dr., University Hospital Zurich, Department of Pulmonology; Principal Investigator: Talant M Sooronbaev, Prof. Dr., National Center of Cardiology and Internal Medicine named after academician M.Mirrakhimov

Study record dates

Study Major Dates

• Study Start (Actual): July 2, 2024
• Primary Completion (Actual): July 12, 2024
• Study Completion (Actual): July 12, 2024

Study Registration Dates

• First Submitted: June 28, 2024
• First Submitted That Met QC Criteria: June 28, 2024
• First Posted (Actual): July 8, 2024

Study Record Updates

• Last Update Posted (Actual): January 22, 2026
• Last Update Submitted That Met QC Criteria: January 19, 2026
• Last Verified: January 1, 2026

More Information

Terms related to this study

• Keywords: Sleep disordered breathing; Pulmonary Hypertension; Hypoxia; High Altitude
• 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; Hypoxia; Sleep Apnea Syndromes; Hypertension, Pulmonary; Altitude Sickness; Pulmonary edema of mountaineers
• Other Study ID Numbers: HAPH_HAvsLA_SDB

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

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