Effects of Iron on Exercise Capacity During Hypoxia

NCT01265108 | Completed Phase 1

• 1 other identifier: OHSRC-986
• Study Type: interventional
• Target: 12
• Locations: 1 country
• Sites: 1

Brief Summary

During alveolar hypoxia, for example at high altitude or in patients with respiratory disease, there is evidence to suggest that hypoxia-induced pulmonary hypertension might limit exercise performance. Intravenous iron supplementation has recently been shown to reverse pulmonary hypertension in healthy humans at high altitude, and to prevent pulmonary hypertension in volunteers exposed to hypoxia at sea level. The investigators hypothesized that intravenous iron supplementation would enhance exercise capacity during alveolar hypoxia.

Conditions

Healthy Volunteers

Outcome Measures

Primary Outcomes (1)

• Maximal exercise capacity during hypoxia, assessed by maximal oxygen consumption.

  Volunteers will receive either intravenous iron or saline placebo, before exposure to 8 hours of alveolar hypoxia. They will then undergo an exercise test while breathing an hypoxic gas mixture. The primary outcome measure will be exercise capacity as determined by maximal oxygen consumption during this test. Volunteers will receive both interventions, via a crossover design. Due to uncertainty about the duration of action of iron at a cellular level, all volunteers will receive saline infusion on the first study day, and iron sucrose infusion on a second study day, at least one week later.

  After 8-h exposure to alveolar hypoxia.

Secondary Outcomes (3)

• Maximal exercise capacity, assessed by peak power output.

  After 8-h exposure to alveolar hypoxia.

• Pulmonary artery systolic pressure.

  After 8-h exposure to alveolar hypoxia.

• Blood levels of oxygen-regulated proteins.

  After 8-h exposure to alveolar hypoxia

Study Arms (2)

Intravenous iron sucrose

EXPERIMENTAL

Infusion of 200 mg iron sucrose (Venofer) in 100 ml normal (0.9%) saline.

Drug: Iron sucrose.

Intravenous normal saline

PLACEBO COMPARATOR

Infusion of 100 ml normal (0.9%) saline.

Drug: Normal saline

Interventions

Iron sucrose. DRUG

Volunteers will receive an intravenous infusion of 200 mg iron sucrose, before exposure to 8 hours of alveolar hypoxia. At the end of the exposure, pulmonary artery systolic pressure will be measured and volunteers will undertake an exercise test while breathing hypoxic gas.

Also known as: Iron sucrose = Venofer

Intravenous iron sucrose

Normal saline DRUG

Volunteers will receive an intravenous infusion of 100 ml normal saline, before exposure to 8 hours of alveolar hypoxia. At the end of the exposure, pulmonary artery systolic pressure will be measured and volunteers will undertake an exercise test while breathing hypoxic gas.

Intravenous normal saline

Eligibility Criteria

• Age: 18 Years - 60 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Age between 18 and 60 years
• Sea level natives with no recent exposure to high altitude
• Baseline iron indices within the normal range
• Detectable tricuspid regurgitation on echocardiography

You may not qualify if:

• Significant cardiorespiratory disease
• Known susceptibility to high altitude-related illness
• Taking medications or iron supplementation
• Pregnancy

Sponsors & Collaborators

• University of Oxford: lead

Study Sites (1)

Department of Physiology, Anatomy & Genetics, University of Oxford

Oxford, OX1 3PT, United Kingdom

Location

MeSH Terms

Interventions

Ferric Oxide, Saccharated; Saline Solution

Intervention Hierarchy (Ancestors)

Ferric Compounds; Iron Compounds; Inorganic Chemicals; Glucaric Acid; Sugar Acids; Acids, Acyclic; Carboxylic Acids; Organic Chemicals; Hydroxy Acids; Carbohydrates; Crystalloid Solutions; Isotonic Solutions; Solutions; Pharmaceutical Preparations

Study Officials

• Nick P Talbot, DPhil MRCP

  University of Oxford

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: phase 1
• Allocation: NON RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, INVESTIGATOR
• Purpose: BASIC SCIENCE
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: December 21, 2010
• First Posted: December 22, 2010
• Study Start: November 1, 2010
• Primary Completion: January 1, 2015
• Study Completion: April 1, 2015
• Last Updated: July 29, 2015

Record last verified: 2015-07

Locations

GB (1)