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

Study Description

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Study Description Study Design Groups and Cohorts Outcome Measures Eligibility Criteria Contacts and Locations More Information

Brief Summary:

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 or disease
High Altitude Pulmonary Hypertension; Sleep Apnea

Study Design

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Study Description Study Design Groups and Cohorts Outcome Measures Eligibility Criteria Contacts and Locations More Information

Study Type :	Observational
Actual Enrollment :	125 participants
Observational Model:	Case Control
Time Perspective:	Prospective
Official Title:	Sleep Apnea and High Altitude Pulmonary Hypertension in Kyrgyz Highlanders
Study Start Date :	June 2012
Actual Primary Completion Date :	December 2013
Actual Study Completion Date :	December 2013

Groups and Cohorts

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Study Description Study Design Groups and Cohorts Outcome Measures Eligibility Criteria Contacts and Locations More Information

Group/Cohort
High altitude pulmonary hypertension; Highlanders with high altitude pulmonary hypertension
High altitude control; Healthy highlanders
Low altitude control; Healthy lowlanders

Outcome Measures

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Study Description Study Design Groups and Cohorts Outcome Measures Eligibility Criteria Contacts and Locations More Information

Primary Outcome Measures :

1. Sleep related breathing disturbances [ Time Frame: 4 months ]
   Nocturnal oxygen saturation and apnea/hypopnea index

Secondary Outcome Measures :

1. Pulmonary artery pressure [ Time Frame: 4 months ]
   Echocardiography
2. Dyspnea [ Time Frame: 4 months ]
   NYHA functional class
3. Vigilance [ Time Frame: 4 months ]
   Psychomotor vigilance
4. Exercise performance [ Time Frame: 4 months ]
   6 min walk test
5. Pulmonary function [ Time Frame: 4 months ]
   Spirometry
6. Cerebral oxygen saturation [ Time Frame: 4 months ]
   Near-infrared spectroscopy
7. Mountain sickness [ Time Frame: 4 months ]
   Quinghai chronic mountain sickness score
8. Generic quality of life [ Time Frame: 4 months ]
   SF-36 quality of life questionnaire
9. Disease specific quality of life [ Time Frame: 4 months ]
   Kansas City Cardiomyopathy questionnaire
10. Subjective sleepiness [ Time Frame: 4 months ]
    Epworth sleepiness scale

Eligibility Criteria

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Study Description Study Design Groups and Cohorts Outcome Measures Eligibility Criteria Contacts and Locations More Information

Ages Eligible for Study:	16 Years and older (Child, Adult, Senior)
Sexes Eligible for Study:	All
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

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Study Description Study Design Groups and Cohorts Outcome Measures Eligibility Criteria Contacts and Locations More Information

Locations

Kyrgyzstan
National Center for Cardiology and Internal Medicine
Bishkek, Kyrgyzstan, 720040

Sponsors and Collaborators

University of Zurich

National Center of Cardiology and Internal Medicine, Kyrgyzstan

Investigators

Principal Investigator:	Konrad E Bloch, MD	University of Zurich, Switzerland
Principal Investigator:	Talant Sooronbaev, MD	National Center of Cardiology and Internal Medicine, Kyrgyzstan

More Information

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Study Description Study Design Groups and Cohorts Outcome Measures Eligibility Criteria Contacts and Locations More Information

Responsible Party:	Konrad E. Bloch, Professor, University of Zurich
ClinicalTrials.gov Identifier:	NCT01621061 History of Changes
Other Study ID Numbers:	01-7/219
First Posted:	June 15, 2012
Last Update Posted:	May 15, 2014
Last Verified:	May 2014

Keywords provided by Konrad E. Bloch, University of Zurich:

high altitude illness; pulmonary hypertension; sleep apnea; hypoxia

Additional relevant MeSH terms:

Hypertension; Hypertension, Pulmonary; Lung Diseases; Apnea; Sleep Apnea Syndromes; Altitude Sickness; Vascular Diseases; Cardiovascular Diseases	Respiration Disorders; Respiratory Tract Diseases; Signs and Symptoms, Respiratory; Signs and Symptoms; Sleep Disorders, Intrinsic; Dyssomnias; Sleep Wake Disorders; Nervous System Diseases