NCT00809744

Brief Summary

In this study the investigators want to compare glucose handling (insulin secretion and insulin sensitivity) in 100 persons with low and 50 persons with normal-high levels of vitamin D, using a hyperglycemic clamp technique, were sugar is given intravenously for 3 hours in order to keep the blood sugar level at 10 mmol/L. Those with low vitamin D levels will be randomized to treatment with vitamin D3 (cholecalciferol) 40 000 IU/week or placebo for 6 months before a new clamp is performed. The study hypothesis is that persons with low vitamin D levels have impaired glucose handling which might be improved by vitamin D supplementation.

Trial Health

87
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
160

participants targeted

Target at P75+ for phase_2

Timeline
Completed

Started Nov 2008

Geographic Reach
1 country

1 active site

Status
completed

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

Study Start

First participant enrolled

November 1, 2008

Completed
2 months until next milestone

First Submitted

Initial submission to the registry

December 16, 2008

Completed
1 day until next milestone

First Posted

Study publicly available on registry

December 17, 2008

Completed
2 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

December 1, 2010

Completed
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

December 1, 2010

Completed
Last Updated

November 3, 2011

Status Verified

November 1, 2011

Enrollment Period

2.1 years

First QC Date

December 16, 2008

Last Update Submit

November 2, 2011

Conditions

Outcome Measures

Primary Outcomes (2)

  • insulin secretion and sensitivity as assessed by an hyperglycemic clamp

    6 months

  • intraocular pressure

    6 months

Secondary Outcomes (4)

  • telomer length

    6 months

  • 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D-levels

    6 months

  • serum calcium, PTH, phosphate

    6 months

  • inflammatory markers and lipids

    6 months

Interventions

capsules, 20 000IU, twice a week, 6 months duration

Eligibility Criteria

Age30 Years - 75 Years
Sexall
Healthy VolunteersNo
Age GroupsAdult (18-64), Older Adult (65+)

You may qualify if:

  • generally: Subjects are recruited from the 6th Tromsø Study
  • cases: serum 25-hydroxyvitamin D-levels below the 10 percentile; low levels confirmed with new serum analyses.
  • controls: serum 25-hydroxyvitamin D levels 80-95 percentile, normal-high levels confirmed with new serum analyses.

You may not qualify if:

  • diabetes
  • myocardial infarction or apoplexia
  • active cancer during last 5 years
  • history of kidney stone
  • pregnancy or premenopausal without safe anticonception
  • primary hyperparathyroidism
  • systolic blood pressure \>175 or diastolic blood pressure \>105

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

University Hospital of North Norway

Tromsø, 9037, Norway

Location

Related Publications (1)

  • Grimnes G, Figenschau Y, Almas B, Jorde R. Vitamin D, insulin secretion, sensitivity, and lipids: results from a case-control study and a randomized controlled trial using hyperglycemic clamp technique. Diabetes. 2011 Nov;60(11):2748-57. doi: 10.2337/db11-0650. Epub 2011 Sep 12.

MeSH Terms

Conditions

Insulin Resistance

Interventions

Cholecalciferol

Condition Hierarchy (Ancestors)

HyperinsulinismGlucose Metabolism DisordersMetabolic DiseasesNutritional and Metabolic Diseases

Intervention Hierarchy (Ancestors)

CholestenesCholestanesSteroidsFused-Ring CompoundsPolycyclic CompoundsSterolsVitamin DSecosteroidsMembrane LipidsLipids

Study Officials

  • Rolf Jorde, Professor

    Medical Dpt, University Hospital of Northern Norway

    PRINCIPAL INVESTIGATOR

Study Design

Study Type
interventional
Phase
phase 2
Allocation
RANDOMIZED
Masking
QUADRUPLE
Who Masked
PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
Purpose
BASIC SCIENCE
Intervention Model
PARALLEL
Sponsor Type
OTHER
Responsible Party
SPONSOR

Study Record Dates

First Submitted

December 16, 2008

First Posted

December 17, 2008

Study Start

November 1, 2008

Primary Completion

December 1, 2010

Study Completion

December 1, 2010

Last Updated

November 3, 2011

Record last verified: 2011-11

Locations