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Chronic Mountain Sickness, Systemic Vascular Function (CMS)

The recruitment status of this study is unknown. The completion date has passed and the status has not been verified in more than two years.
Verified September 2013 by Urs Scherrer, University of Lausanne Hospitals.
Recruitment status was:  Active, not recruiting
Instituto Boliviano de Biologia de Altura
Universitad Major de S. Andres, La Paz, Bolivia
Information provided by (Responsible Party):
Urs Scherrer, University of Lausanne Hospitals Identifier:
First received: August 16, 2010
Last updated: September 5, 2013
Last verified: September 2013

Diseases associated with chronic hypoxemia like chronic obstructive pulmonary disease (COPD) or emphysema, represent major medical and socio-economical problems and one of the leading cause of morbidity and mortality in the western countries. Recently, is has been shown that cardiovascular (CV) diseases contribute highly to the morbidity and mortality of these patients. Furthermore, increasing evidence suggest that systemic vascular dysfunction play a central role in the mediation of the increased CV risk in patients with COPD. However the underlying mechanisms of vascular dysfunction in these patients are incompletely understood. Chronic mountain sickness (CMS) is characterized by chronic hypoxemia related at least in part to hypoventilation; it affects relatively young adults, and may therefore allow to study the effects of chronic hypoxemia. The investigators therefore will assess systemic vascular function and test the hypothesis that increased oxidative stress is responsible for this dysfunction. Since polyglobulia is a hallmark of chronic hypoxemia and has been suggested to affect vascular function, the investigators will test the effects of hemodilution on vascular function. Then, the investigators will test the effects of acute oxygen application and 1 month antioxidative dietary supplement on vascular function.

Preliminary data suggest that offspring of CMS patients may display pulmonary and systemic vascular dysfunction. Antioxidant administration is know to improve vascular function. We will test the acute effect of Vitamin C in this setting.

Finally, since there is considerable inter-individual variability of pulmonary artery pressure among CMS patients and the presence of a patent foramen ovale (PFO)is increased in clinical conditions associated with pulmonary hypertension and hypoxemia, we will assess the prevalence of PFO in healthy high altitude dwellers and in CMS patients and its effects on pulmonary artery pressure at rest and during mild exercise.

Condition Intervention
Mountain Sickness Chronic Dietary Supplement: Vitamin C and E Dietary Supplement: Placebo

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double (Participant, Investigator)
Primary Purpose: Treatment
Official Title: Chronic Hypoxemia and Systemic Vascular Function

Resource links provided by NLM:

Further study details as provided by Urs Scherrer, University of Lausanne Hospitals:

Primary Outcome Measures:
  • Endothelial Function [ Time Frame: 1 month ]

Estimated Enrollment: 50
Study Start Date: October 2008
Estimated Study Completion Date: December 2013
Estimated Primary Completion Date: September 2013 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: Antioxidant Dietary Supplement: Vitamin C and E
1 month, 1g Vitamin C and 400 IE Vitamin E or Acute, 1g Vitamin C (in the offspring)
Placebo Comparator: Control Dietary Supplement: Placebo
1 month Placebo


Ages Eligible for Study:   10 Years and older   (Child, Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • Patients with Chronic Mountain Sickness and their offspring

Exclusion Criteria:

  • Smoking
  • Lung disease
  • Arterial Hypertension
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Please refer to this study by its identifier: NCT01182792

Istituto Boliviano de Biologia de Altura, Universitad S. Andres
La Paz, Bolivia
University Hospital Lausanne, Botnar Center for Extreme Medicine
Lausanne, Vaud, Switzerland, 1011
Sponsors and Collaborators
University of Lausanne Hospitals
Instituto Boliviano de Biologia de Altura
Universitad Major de S. Andres, La Paz, Bolivia
  More Information

Publications automatically indexed to this study by Identifier (NCT Number):

Responsible Party: Urs Scherrer, Prof, University of Lausanne Hospitals Identifier: NCT01182792     History of Changes
Other Study ID Numbers: CMS
Study First Received: August 16, 2010
Last Updated: September 5, 2013

Keywords provided by Urs Scherrer, University of Lausanne Hospitals:
Endothelial Function
Chronic Hypoxia
Oxidative Stress

Additional relevant MeSH terms:
Altitude Sickness
Respiration Disorders
Respiratory Tract Diseases
Ascorbic Acid
Growth Substances
Physiological Effects of Drugs
Molecular Mechanisms of Pharmacological Action
Protective Agents processed this record on September 21, 2017