Sleep Related Breathing Disturbances and High Altitude Pulmonary Hypertension in Kyrgyz Highlanders

This study has been completed.
Sponsor:
Collaborator:
National Center for Cardiology and Internal Medicine, Bishkek, Kyrgyzstan
Information provided by (Responsible Party):
Konrad E. Bloch, University of Zurich
ClinicalTrials.gov Identifier:
NCT01621061
First received: June 13, 2012
Last updated: May 14, 2014
Last verified: May 2014
  Purpose

High altitude pulmonary hypertension, a form of altitude illness that occurs in long-term residents at altitudes >2500 m, is characterized by dyspnea, hypoxemia, impaired exercise performance and hypertension in the pulmonary circulation. Whether sleep related breathing disturbances, common causes of nocturnal hypoxemia in lowlanders, are also prevalent in highlanders and promote pulmonary hypertension in highlanders is unknown. Therefore, the current study will investigate whether highlanders with high altitude pulmonary hypertension have a greater prevalence of sleep apnea than healthy highlanders and lowlanders.


Condition
High Altitude Pulmonary Hypertension
Sleep Apnea

Study Type: Observational
Study Design: Observational Model: Case Control
Time Perspective: Prospective
Official Title: Sleep Apnea and High Altitude Pulmonary Hypertension in Kyrgyz Highlanders

Resource links provided by NLM:


Further study details as provided by University of Zurich:

Primary Outcome Measures:
  • Sleep related breathing disturbances [ Time Frame: 4 months ] [ Designated as safety issue: No ]
    Nocturnal oxygen saturation and apnea/hypopnea index


Secondary Outcome Measures:
  • Pulmonary artery pressure [ Time Frame: 4 months ] [ Designated as safety issue: No ]
    Echocardiography

  • Dyspnea [ Time Frame: 4 months ] [ Designated as safety issue: No ]
    NYHA functional class

  • Vigilance [ Time Frame: 4 months ] [ Designated as safety issue: No ]
    Psychomotor vigilance

  • Exercise performance [ Time Frame: 4 months ] [ Designated as safety issue: No ]
    6 min walk test

  • Pulmonary function [ Time Frame: 4 months ] [ Designated as safety issue: No ]
    Spirometry

  • Cerebral oxygen saturation [ Time Frame: 4 months ] [ Designated as safety issue: No ]
    Near-infrared spectroscopy

  • Mountain sickness [ Time Frame: 4 months ] [ Designated as safety issue: No ]
    Quinghai chronic mountain sickness score

  • Generic quality of life [ Time Frame: 4 months ] [ Designated as safety issue: No ]
    SF-36 quality of life questionnaire

  • Disease specific quality of life [ Time Frame: 4 months ] [ Designated as safety issue: No ]
    Kansas City Cardiomyopathy questionnaire

  • Subjective sleepiness [ Time Frame: 4 months ] [ Designated as safety issue: No ]
    Epworth sleepiness scale


Enrollment: 125
Study Start Date: June 2012
Study Completion Date: December 2013
Primary Completion Date: December 2013 (Final data collection date for primary outcome measure)
Groups/Cohorts
High altitude pulmonary hypertension
Highlanders with high altitude pulmonary hypertension
High altitude control
Healthy highlanders
Low altitude control
Healthy lowlanders

  Eligibility

Ages Eligible for Study:   16 Years and older
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   Yes
Sampling Method:   Non-Probability Sample
Study Population

Highlanders with high altitude pumonary hypertension living at an altitude of 2500-4000 m; healthy highlanders living at an altitude of 2500-4000 m; healthy lowlanders living at an altitude of <1000 m.

Criteria

Inclusion Criteria:

  • high altitude pulmonary hypertension confirmed by clinical presentation and systolic pulmonary artery pressure >50 mmHg measured by echocardiography at altitude of residence.
  • healthy subjects (high altitude controls)
  • Both genders
  • Age >16 y
  • Kyrgyz ethnicity
  • born, raised and currently living at >2500 m
  • healthy subjects currently living at <1000 m (low altitude controls)

Exclusion criteria:

  • Pulmonary hypertension from other causes, in particular from left ventricular failure as judged clinically and by echocardiography
  • excessive erythrocytosis
  • other coexistent disorders that may interfere with the cardio-respiratory system and sleep
  • regular use of medication that affects control of breathing
  • heavy smoking
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT01621061

Locations
Kyrgyzstan
National Center for Cardiology and Internal Medicine
Bishkek, Kyrgyzstan, 720040
Sponsors and Collaborators
University of Zurich
National Center for Cardiology and Internal Medicine, Bishkek, Kyrgyzstan
Investigators
Principal Investigator: Konrad E Bloch, MD University of Zurich, Switzerland
Principal Investigator: Talant Sooronbaev, MD National Center for Cardiology and Internal Medicine, Bishkek, Kyrgyzstan
  More Information

No publications provided

Responsible Party: Konrad E. Bloch, Professor, University of Zurich
ClinicalTrials.gov Identifier: NCT01621061     History of Changes
Other Study ID Numbers: 01-7/219
Study First Received: June 13, 2012
Last Updated: May 14, 2014
Health Authority: Kyrgyzstan: Research Ethics Committee

Keywords provided by University of Zurich:
high altitude illness
pulmonary hypertension
sleep apnea
hypoxia

Additional relevant MeSH terms:
Apnea
Hypertension
Hypertension, Pulmonary
Sleep Apnea Syndromes
Altitude Sickness
Respiration Disorders
Respiratory Tract Diseases
Signs and Symptoms, Respiratory
Signs and Symptoms
Vascular Diseases
Cardiovascular Diseases
Lung Diseases
Sleep Disorders, Intrinsic
Dyssomnias
Sleep Disorders
Nervous System Diseases

ClinicalTrials.gov processed this record on July 22, 2014