Identification of the Region of Vitamin D Responsiveness (GRH-PN01)

This study has been completed.
Sponsor:
Information provided by (Responsible Party):
Creighton University
ClinicalTrials.gov Identifier:
NCT01692028
First received: September 13, 2012
Last updated: September 21, 2012
Last verified: September 2012
  Purpose

Hypothesis: low vitamin D status is associated with increased insulin resistance and increased blood pressure.

Approach: Multiple regression analysis of information extracted from a large database accumulated by a Canadian health foundation, specifically evaluating statistical associations between serum 25(OH)D levels and insulin responsiveness measures as well as blood pressure, after adjusting these variables for BMI, age, sex, and waist circumference.


Condition
Diabetes
Hypertension

Study Type: Observational
Study Design: Observational Model: Ecologic or Community
Time Perspective: Cross-Sectional
Official Title: A Novel Approach Localizes the Association of Vitamin D Status With Insulin Resistance to One Region of the 25(OH)D Continuum.

Resource links provided by NLM:


Further study details as provided by Creighton University:

Primary Outcome Measures:
  • HOMA-IR [ Time Frame: Observational/cross-sectional study ] [ Designated as safety issue: No ]
    A composite measure of insulin resistance (HOMA-IR)


Secondary Outcome Measures:
  • Blood pressure [ Time Frame: cross-sectional study ] [ Designated as safety issue: No ]
    Blood Pressure


Enrollment: 4116
Study Start Date: February 2012
Study Completion Date: February 2012
Primary Completion Date: February 2012 (Final data collection date for primary outcome measure)
Detailed Description:

Data obtained from the entry records of 4,116 adult men and women in Calgary,Alberta previously enrolled in the Pure North S'Energy Foundation's health program. Individuals with a clinical diagnosis of diabetes mellitus or a HOMA-IR value above 16 were excluded. Standard statistical analyses carried out. An association between 25(OH)D and the endpoints of interest was first established. The residual values after adjusting HOMA-IR, serum insulin, QUICKI, and blood pressure for BMI, age, sex, and waist circumference were then regressed against serum 25(OH)D using 40-percentile data blocks, stepping upward from the lowest 25(OH)D values by 5 percentile increments through the 7th decile. Regression coefficients are then computed for each data block and each outcome variable. The location (along the 25(OF)D continuum) of the largest and most statistically significant coefficients is noted, and regions of null response noted as well.

  Eligibility

Ages Eligible for Study:   18 Years to 95 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   Yes
Sampling Method:   Non-Probability Sample
Study Population

Healthy adults living in or near Calgary and associated with the oil and gas industries

Criteria

Inclusion Criteria:

  • Age > 18

Exclusion Criteria:

  • Diabetes
  • Elevated HOMA-IR (>16)
  Contacts and Locations
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Please refer to this study by its ClinicalTrials.gov identifier: NCT01692028

Locations
Canada, Alberta
Pure North S'Energy Foundataion
Calgary, Alberta, Canada
Sponsors and Collaborators
Creighton University
  More Information

No publications provided

Responsible Party: Creighton University
ClinicalTrials.gov Identifier: NCT01692028     History of Changes
Other Study ID Numbers: GRH-PN01
Study First Received: September 13, 2012
Last Updated: September 21, 2012
Health Authority: United States: Federal Government

Keywords provided by Creighton University:
vitamin D
Associational study

Additional relevant MeSH terms:
Hypertension
Vascular Diseases
Cardiovascular Diseases
Vitamin D
Vitamins
Micronutrients
Growth Substances
Physiological Effects of Drugs
Pharmacologic Actions
Bone Density Conservation Agents

ClinicalTrials.gov processed this record on September 18, 2014