Vitamin D AND Glucose Handling Evaluated by Glucose Clamp

Insulin Sensitivity Clinical Trial

— D-clamp  

Official title:

Vitamin D AND Cardiovascular Disease

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT00809744
• Other study ID #: UIT-ENDO-2008-GURI-2
• Status: Completed
• Phase: Phase 2
• First received: December 16, 2008
• Last updated: November 2, 2011
• Start date: November 2008
• Est. completion date: December 2010

Study information

• Verified date: November 2011
• Source: University Hospital of North Norway
• Contact: n/a
• Is FDA regulated: No
• Health authority: Norway: Norwegian Medicines AgencyNorway:National Committee for Medical and Health Research EthicsNorway: Norwegian Social Science Data ServicesNorway: Directorate of Health
• Study type: Interventional

Clinical Trial 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.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 160
• Est. completion date: December 2010
• Est. primary completion date: December 2010
• Accepts healthy volunteers: No
• Gender: Both
• Age group: 30 Years to 75 Years

Eligibility

Inclusion Criteria:

• 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.

Exclusion Criteria:

• 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

Study Design

Allocation: Randomized, Endpoint Classification: Efficacy Study, Intervention Model: Parallel Assignment, Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor), Primary Purpose: Basic Science

Related Conditions & MeSH terms

• Insulin Sensitivity
• Intraocular Pressure

Intervention

Drug:
• cholecalciferol
capsules, 20 000IU, twice a week, 6 months duration

Locations

Country	Name	City	State
Norway	University Hospital of North Norway	Tromsø

Sponsors (2)

Lead Sponsor	Collaborator
University Hospital of North Norway	Norwegian Council on Cardiovascular diseases

Country where clinical trial is conducted

Norway, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	insulin secretion and sensitivity as assessed by an hyperglycemic clamp		6 months	No
Primary	intraocular pressure		6 months	No
Secondary	telomer length		6 months	No
Secondary	25-hydroxyvitamin D and 1,25-dihydroxyvitamin D-levels		6 months	No
Secondary	serum calcium, PTH, phosphate		6 months	Yes
Secondary	inflammatory markers and lipids		6 months	No