Planetary Habitat Simulation: Bone Metabolism Studies

NCT02637921 | Completed DMC

• 1 other identifier: 284438/WP3
• Study Type: interventional
• Target: 14
• Locations: 0 countries
• Sites: N/A

Brief Summary

Bone losses are well known to occur in response to unloading (in microgravity or during immobilisation) and in patients with chronic obstructive airway disease (COPD). However, it is unknown whether there is an interactive effect between hypoxia and musculoskeletal unloading upon bone and mineral metabolism. Fourteen non-obese men, who are otherwise healthy, will undergo 3x 21-day interventions; normobaric normoxic bed rest (NBR; FiO2=21%), normobaric hypoxic ambulatory confinement (HAMB; FiO2=14%; \~4000 m simulated altitude), and normobaric hypoxic bed rest (HBR; FiO2=14%). The effects of hypoxia and bedrest on bone metabolism and phosphor-calcic homeostasis will be assessed (before and during each intervention, and 14 days after each intervention period) using venous blood sampling, 24hr urine collections, and peripheral quantitative computerized tomography (pQCT).

Conditions

Hypoxia; Bone Resorption

Keywords

bed rest; bone metabolism

Outcome Measures

Primary Outcomes (1)

• Change in bone mineral content, from baseline

  assessed before (day -5), on days 2, 10 and 21 of the intervention and at the 14-day follow-up visit (40 days after 1st measurement) using pQCT scans of the calf and thigh.

  40 days

Secondary Outcomes (11)

• Change in urinary calcium concentration, from baseline

  30 days

• Change in urinary phosphate concentration, from baseline

  31 days

• Change in urinary N-terminal telopeptide concentration, from baseline

  31 days

• Change in fasting serum calcium concentration, from baseline

  26 days

• Change in fasting serum phosphate concentration, from baseline

  26 days

Study Arms (3)

Hypoxic ambulatory

ACTIVE COMPARATOR

Participants ambulatory in normobaric hypoxia with standardised nutritional intake

Other: Hypoxia; Other: Ambulatory; Other: Standardised nutritional intake

Hypoxic Bed rest

EXPERIMENTAL

Participants are on bed rest in normobaric hypoxia with standardised nutritional intake

Other: Hypoxia; Other: Bed Rest; Other: Standardised nutritional intake

Normoxic bed rest

ACTIVE COMPARATOR

Participants are on bed rest in normobaric normoxia with standardised nutritional intake

Other: Normoxia; Other: Bed Rest; Other: Standardised nutritional intake

Interventions

Hypoxia OTHER

21 days confinement in normobaric hypoxic (FiO2 = 14%)

Hypoxic Bed rest; Hypoxic ambulatory

Ambulatory OTHER

Participants hava a standardized activity level throughout the intervention

Hypoxic ambulatory

Normoxia OTHER

21 days confinement in normobaric normoxic (FiO2 = 21%) environment

Normoxic bed rest

Bed Rest OTHER

Participants remain on supine bed rest throughout the intervention

Hypoxic Bed rest; Normoxic bed rest

Standardised nutritional intake OTHER

Macronutrient, salt and dietary energy intake will be standardized per kg body weight for each participant

Hypoxic Bed rest; Hypoxic ambulatory; Normoxic bed rest

Eligibility Criteria

• Age: 25 Years - 45 Years
• Sex: male
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Physically and mentally healthy subjects
• Body mass index \< 25 kg/m2
• Height 158 - 190 cm
• Waist circumference \< 94 cm
• Volunteers that are able to declare their willingness to participate in the entire study
• Willing to be assigned randomly to the three groups
• Successfully passing the psychological and medical screening
• competent to sign informed consent
• Slovenian social insurance
• English language fluency

You may not qualify if:

• Medication required that may interfere with the interpretation of the results
• Bone mineral density (as measured by DEXA) more than 1.5 standard deviations \< t score
• Recent sub-standard nutritional status
• Family history of thrombosis or positive response in thrombosis screening procedure.
• (Biochemical analysis of the following parameters: ATIII, High sensitive C-reactive protein, S-Akt., Factor V-Leiden, Prothrombin, Lupus-partial thromboplastin time, Factor II)
• History of: thyroid dysfunction, renal stones, diabetes, allergies, hypertension, hypocalcemia, uric acidaemia, lipidaemia, or hyperhomocysteinaemia
• Gastro-esophageal reflux disease or renal function disorder, Hiatus hernia
• History of medical illness
• Smoker within six months prior to the start of the study
• Abuse of drugs, medicine or alcohol
• Participation in another study up to two months before study onset
• No signed consent form before the onset of the experiment
• Blood donors in the past three months before the onset of the experiment
• Vegetarian and Vegans
• Migraines

Sponsors & Collaborators

• University of Nottingham: lead
• Jozef Stefan Institute: collaborator
• DLR German Aerospace Center: collaborator
• KTH Royal Institute of Technology: collaborator
• European Commission: collaborator

Related Publications (1)

• Rittweger J, Debevec T, Frings-Meuthen P, Lau P, Mittag U, Ganse B, Ferstl PG, Simpson EJ, Macdonald IA, Eiken O, Mekjavic IB. On the combined effects of normobaric hypoxia and bed rest upon bone and mineral metabolism: Results from the PlanHab study. Bone. 2016 Oct;91:130-8. doi: 10.1016/j.bone.2016.07.013. Epub 2016 Jul 18.

  PMID: 27443510 RESULT

MeSH Terms

Conditions

Hypoxia; Bone Resorption

Interventions

Ambulatory Care Facilities; Bed Rest

Condition Hierarchy (Ancestors)

Signs and Symptoms, Respiratory; Signs and Symptoms; Pathological Conditions, Signs and Symptoms; Bone Diseases; Musculoskeletal Diseases

Intervention Hierarchy (Ancestors)

Health Facilities; Health Care Facilities Workforce and Services; Therapeutics

Study Officials

• Igor Mekjavic, PhD

  Jozef Stefan Institute

  STUDY DIRECTOR

• Jörn Rittweger, MD, PhD

  German Aerospace Center (DLR)

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: BASIC SCIENCE
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Dr

Study Record Dates

• First Submitted: December 1, 2015
• First Posted: December 22, 2015
• Study Start: March 1, 2012
• Primary Completion: November 1, 2013
• Study Completion: September 1, 2015
• Last Updated: March 15, 2019

Record last verified: 2019-03

Data Sharing

• IPD Sharing: Will not share