Iron Status and Hypoxic Pulmonary Vascular Responses
Status:
Completed
Trial end date:
2014-04-01
Target enrollment:
Participant gender:
Summary
On exposure to hypoxia (low oxygen) the normal response is for pulmonary arterial systolic
blood pressure (PASP, blood pressure through the lungs) to increase. We have previously shown
that raising iron by giving an infusion of iron into a vein reduces this pressure rise and
that lowering iron by giving a drug that binds iron, magnifies this response. This is
potentially a clinically important observation since iron-deficient people may be at
increased risk of pulmonary hypertension if exposed transiently or permanently to hypoxia due
to lung disease or residence at high altitude; furthermore if this were true then intravenous
iron could be an important treatment in this patient group in the event of hypoxic exposure.
The observed effects of iron on PASP are likely to be because iron levels affect oxygen
sensing. Low iron levels make the body behave as if exposed to low oxygen by inhibiting the
breakdown of the family of oxygen-sensing transcription factors, 'hypoxia inducible factor'
or HIF. This includes one of the body's normal responses to low oxygen levels - raising blood
pressure through the lungs.
This study will answer the question (1) do iron-deficient volunteers have a greater rise in
PASP with hypoxia than those who are iron-replete, and (2) does giving intravenous iron cause
a greater reduction in the rise in PASP in those who are iron-deficient than iron-replete?
The purpose of this study is not to test the safety or clinical efficacy of iron which is
already known.
Phase:
N/A
Details
Lead Sponsor:
University of Oxford
Collaborators:
British Heart Foundation National Institute for Health Research, United Kingdom