Effects of Iron on Exercise Capacity During Hypoxia

The recruitment status of this study is unknown because the information has not been verified recently.
Verified July 2012 by University of Oxford.
Recruitment status was  Active, not recruiting
Sponsor:
Information provided by (Responsible Party):
University of Oxford
ClinicalTrials.gov Identifier:
NCT01265108
First received: December 21, 2010
Last updated: July 31, 2012
Last verified: July 2012
  Purpose

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.


Condition Intervention Phase
Healthy Volunteers
Drug: Iron sucrose.
Drug: Normal saline
Phase 1

Study Type: Interventional
Study Design: Allocation: Non-Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Crossover Assignment
Masking: Double Blind (Subject, Investigator)
Primary Purpose: Basic Science
Official Title: Effects of Intravenous Iron Supplementation on Exercise Capacity During Sustained Alveolar Hypoxia in Healthy Humans.

Resource links provided by NLM:


Further study details as provided by University of Oxford:

Primary Outcome Measures:
  • Maximal exercise capacity during hypoxia, assessed by maximal oxygen consumption. [ Time Frame: After 8-h exposure to alveolar hypoxia. ] [ Designated as safety issue: No ]
    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.


Secondary Outcome Measures:
  • Maximal exercise capacity, assessed by peak power output. [ Time Frame: After 8-h exposure to alveolar hypoxia. ] [ Designated as safety issue: No ]
  • Pulmonary artery systolic pressure. [ Time Frame: After 8-h exposure to alveolar hypoxia. ] [ Designated as safety issue: No ]
  • Blood levels of oxygen-regulated proteins. [ Time Frame: After 8-h exposure to alveolar hypoxia ] [ Designated as safety issue: No ]

Estimated Enrollment: 12
Study Start Date: November 2010
Estimated Study Completion Date: December 2012
Estimated Primary Completion Date: December 2012 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: Intravenous iron sucrose
Infusion of 200 mg iron sucrose (Venofer) in 100 ml normal (0.9%) saline.
Drug: Iron sucrose.
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.
Other Name: Iron sucrose = Venofer
Placebo Comparator: Intravenous normal saline
Infusion of 100 ml normal (0.9%) saline.
Drug: Normal saline
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.

  Eligibility

Ages Eligible for Study:   18 Years to 60 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   Yes
Criteria

Inclusion Criteria:

  • 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

Exclusion Criteria:

  • Significant cardiorespiratory disease
  • Known susceptibility to high altitude-related illness
  • Taking medications or iron supplementation
  • Pregnancy
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT01265108

Locations
United Kingdom
Department of Physiology, Anatomy & Genetics, University of Oxford
Oxford, United Kingdom, OX1 3PT
Sponsors and Collaborators
University of Oxford
Investigators
Principal Investigator: Nick P Talbot, DPhil MRCP University of Oxford
  More Information

No publications provided

Responsible Party: University of Oxford
ClinicalTrials.gov Identifier: NCT01265108     History of Changes
Other Study ID Numbers: OHSRC-986
Study First Received: December 21, 2010
Last Updated: July 31, 2012
Health Authority: United Kingdom: Research Ethics Committee

Additional relevant MeSH terms:
Iron
Ferric oxide, saccharated
Ferric Compounds
Trace Elements
Micronutrients
Growth Substances
Physiological Effects of Drugs
Pharmacologic Actions
Hematinics
Hematologic Agents
Therapeutic Uses

ClinicalTrials.gov processed this record on September 18, 2014