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OpenTrials
Completed

NCT Number: NCT02930434

Effects of Antarctic Environment on Vitamin D Status and Health Risk Biomarkers of Its Inhabitants

The purpose of this study is to evaluate vitamin D (VD) deficiency in the population of Chilean Antarctica and evaluate the efficacy and safety of VD supplementation to decrease VD deficiency and favorably influence biomarkers for bone, cardiovascular, and immune health risk in the inhabitants of Chilean Antarctica.

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Key information

Conditions

Vitamin D Deficiency Avitaminosis Deficiency Diseases Malnutrition Nutrition Disorders Nutritional and Metabolic Diseases

Age range

Up to 100 year

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

About this study

The present study consists of an initial cross-sectional evaluation of VD status and specific health biomarkers in inhabitants of Chilean Antarctica, followed by a randomized controlled trial evaluating two acceptable approaches of vitamin D supplementation (cholecalciferol 600 IU daily vs. 25000 IU weekly) in Antarctic inhabitants.

Who can participate

Healthy volunteers accepted: Yes

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • population of all ages living in the Chilean Antarctic territory during at least 3 months.

Exclusion criteria

  • acute or chronic renal disease
  • hyper or hypocalcemia
  • osteomalacia or Paget's disease of bone
  • use of VD supplements or fish oil supplements in the past month in doses higher than 400 IU daily
  • treatment for known VD deficiency in the last 6 months
  • UV phototherapy in the past month.

Treatment and study plan

Cholecalciferol

Dietary Supplement

Administration of vitamin D3

Other names: Vitamin D3

Primary outcomes

  1. Change in serum 25-hydroxyvitamin D concentration

    Time frame: at end of Antarctic residency or 1 year (90-365 days), whichever came first

    In Antarctic inhabitants not supplemented with VD that exit Antarctica before start of RCT phase of study.

Secondary outcomes

  1. sun exposure

    Time frame: at 0, 6, 12 months of Antarctic residency

    questionnaires

  2. sleep pattern

    Time frame: at 0, 6, 12 months of Antarctic residency

    questionnaires

  3. food intake of VD

    Time frame: at 0, 6, 12 months of Antarctic residency

    Food frequency questionnaire

  4. serum biomarkers for bone metabolism

    Time frame: at baseline and every 3 months during supplementation (3,6,9,12 months) up to end of Antarctic residency or 1 year (90-365 days), whichever came first

    intact PTH, calcium phosphorus, alkaline phosphatases, VD-binding protein

  5. serum high-sensitivity C-reactive protein (hsCRP)

    Time frame: at baseline and every 3 months during supplementation (3,6,9,12 months) up to end of Antarctic residency or 1 year (90-365 days), whichever came first

  6. serum cathelicidin (LL-37) concentration

    Time frame: at baseline and every 3 months during supplementation (3,6,9,12 months) up to end of Antarctic residency or 1 year (90-365 days), whichever came first

Sponsors and collaborators

Lead sponsor

Pontificia Universidad Catolica de Chile

Other

Collaborators

  • Fuerza Aérea de Chile
  • Harvard Medical School (HMS and HSDM)
  • Instituto Antártico Chileno

Registry information

Acronym: AntarD

Important dates

Study start
2016
Primary completion
2017
Study completion
2018
First posted
Oct 12, 2016
Registry last updated
Mar 13, 2018

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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