Clinical Trial: Study of the Effects of Iron on Lung Blood Pressure at High Altitude

Study Status: Withdrawn
Recruit Status: Withdrawn
Study Type: Interventional

Official Title: Study of the Effects of Iron Supplementation on High Altitude Pulmonary Hypertension.

Brief Summary: Body iron levels may be important in determining how the blood pressure in the lungs changes in response to low oxygen levels. At high altitude, where oxygen levels are low, some patients develop elevated lung blood pressure. The investigators hypothesize that, in high altitude residents with elevated lung blood pressure, iron supplementation will cause a reduction in lung blood pressure.

Detailed Summary:

Pulmonary hypertensive disorders frequently complicate hypoxic lung disease and worsen patient survival.

Hypoxia-induced pulmonary hypertension is also a major cause of morbidity at high altitude. Hypoxia causes pulmonary hypertension through hypoxic pulmonary vasoconstriction and vascular remodelling. These processes are thought to be regulated at least in part by the hypoxia-inducible factor (HIF) family of transcription factors, which coordinate intracellular responses to hypoxia throughout the body.

HIF is regulated through a cellular degradation process that requires iron as an obligate cofactor. In cultured cells HIF degradation is inhibited by reduced iron availability (by chelation with desferrioxamine) and potentiated by iron supplementation. In humans, laboratory experiments lasting eight hours have shown that acute iron supplementation blunts the pulmonary vascular response to hypoxia, while acute iron chelation with desferrioxamine enhances the response.

These findings suggest that iron may also affect the pulmonary vascular response to hypoxia over longer time periods. The purpose of this study, which will take place at high altitude in Kyrgyzstan, is to investigate whether iron supplementation can reduce pulmonary artery pressure in patients with established high altitude pulmonary hypertension.

Sponsor: University of Oxford

Current Primary Outcome: Change in pulmonary artery systolic pressure [ Time Frame: 28 days ]

Original Primary Outcome: Same as current

Current Secondary Outcome:

Original Secondary Outcome:

Information By: University of Oxford

Dates:
Date Received: August 17, 2009
Date Started:
Date Completion:
Last Updated: May 12, 2017
Last Verified: May 2017