Now Available for Public Comment: Notice of Proposed Rulemaking (NPRM) for FDAAA 801 and NIH Draft Reporting Policy for NIH-Funded Trials

Effect of Vitamin D3 Supplementation on Insulin Resistance- The DIR Study

This study is currently recruiting participants. (see Contacts and Locations)
Verified November 2013 by Queen's University, Belfast
Sponsor:
Collaborators:
HSC Research & Development Division, Public Health Agency, Northern Ireland
The Metabolic Unit Research Fund, The Royal Hospitals, Belfast, Northern Ireland
NI Chest, Heart & Stroke
Information provided by (Responsible Party):
Michelle McKinley, Queen's University, Belfast
ClinicalTrials.gov Identifier:
NCT01889810
First received: June 26, 2013
Last updated: November 26, 2013
Last verified: November 2013

June 26, 2013
November 26, 2013
August 2013
July 2016   (final data collection date for primary outcome measure)
Change in Insulin Resistance [ Time Frame: Measured at baseline and after 6 months ] [ Designated as safety issue: No ]
Insulin resistance will be measured using the gold standard euglycaemic-hyperinsulinaemic clamp method (note - it is anticipated that a total of 60 volunteers will complete the primary endpoint assessment).
Same as current
Complete list of historical versions of study NCT01889810 on ClinicalTrials.gov Archive Site
  • Change in vitamin D status [ Time Frame: Measured at baseline and after 6 months ] [ Designated as safety issue: No ]
    Change in vitamin D status will be measured using the gold standard Ultra performance liquid chromatography followed by tandem mass spectrometry
  • Change in markers of cardiovascular risk [ Time Frame: Measured at baseline and after 6 months ] [ Designated as safety issue: No ]
    Measurements of seated and 24-hour ambulatory blood pressure, lipids, homeostasis model assessment (HOMA), HbA1c, and inflammatory and immune function markers including tumour necrosis factor-alpha and high sensitivity c-reactive protein
  • Change in carotid-femoral pulse wave velocity (PWV) [ Time Frame: Measured at baseline and after 6 months ] [ Designated as safety issue: No ]
    Assessed by sequential tonometry with ECG gating using the SphygmoCor PWV System
Same as current
Not Provided
Not Provided
 
Effect of Vitamin D3 Supplementation on Insulin Resistance- The DIR Study
Effect of Vitamin D3 Supplementation on Insulin Resistance and Cardiovascular Risk Factors in People at High Risk of Type 2 Diabetes and Cardiovascular Disease (The DIR Study)

Insulin resistance is a state where the body does not respond as it should to the insulin it produces. Individuals who are insulin resistant are at increased risk of both heart disease and type 2 diabetes; importantly, diabetes more than doubles the risk of heart disease, independent of other recognised risk factors. Interventions that prevent or reverse insulin resistance may help to attenuate risk of heart disease and diabetes. A number of randomised controlled trials provide proof of concept evidence regarding a beneficial effect of vitamin D on insulin resistance and other cardiovascular risk markers but experts have stated that further studies are required. Importantly, these studies should use appropriate endpoints, provide a high enough dose of vitamin D to optimise vitamin D status, and they should be conducted in clearly defined populations, The vitamin D trial we propose addresses these issues and aims to evaluate a potentially straightforward and low cost health care intervention for populations at highrisk of heart disease and diabetes. Specifically, this study would provide clinically relevant information on the metabolic effects of optimising vitamin D status in these high risk patients. This has clear economic and social implications given the current, and projected, burden of heart disease and diabetes.

This study will investigate the effect of vitamin D3 supplementation on insulin resistance and cardiovascular risk factors in people at high risk of type 2 diabetes and cardiovascular disease using the gold standard euglycaemic hyperinsulinaemic clamp method.

Not Provided
Interventional
Not Provided
Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Parallel Assignment
Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor)
Primary Purpose: Prevention
  • Sub-optimal Vitamin D Status
  • Pre-diabetes
  • Insulin Resistance
Dietary Supplement: Vitamin D3 supplementation
3000IU (75µg) vitamin D3 will be given daily for a period of 26 weeks to the group who receive the active comparator. The efficacy of vitamin D3 supplementation on insulin resistance will be compared to the placebo group.
  • Active Comparator: Vitamin D3 supplementation
    Patients will take 3000IU (75 µg) Vitamin D3 supplementation per day for a period of 26 weeks.
    Intervention: Dietary Supplement: Vitamin D3 supplementation
  • Placebo Comparator: Placebo
    Placebo group
Not Provided

*   Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
 
Recruiting
94
July 2016
July 2016   (final data collection date for primary outcome measure)

Inclusion Criteria:

  • Impaired glucose tolerance (Fasting glucose <7.0 mmol/L (126mg/dl) and 2hr post-glucose load 7.8-11.0 mmol/L (140-199 mg/dl) or Impaired fasting glucose 5.6-6.9 mmol/L (100-125mg/dL) defined according to American Diabetes Association
  • Sub-optimal vitamin D status (<50nmol/L)

Exclusion Criteria:

  • Diabetes mellitus
  • Established cardiovascular disease
  • Psychiatric problems
  • Pregnant or lactating
  • Medical conditions or dietary restrictions that would substantially limit ability to complete the study requirements
  • Excessive alcohol consumption (>28 Units/week men or >21 Units/week women)
  • Already taking vitamin D supplements > 10 µg/d
  • Medical conditions or medications that could influence vitamin D metabolism
  • History of kidney stones
  • Hypercalcaemia
  • Hyperparathyroidism
  • Significant liver and renal disease (liver function tests >3x upper limit of normal and glomerular filtration rate <30ml/min)
Both
18 Years and older
Yes
Contact: Michelle McKinley, PhD 02890632685 m.mckinley@qub.ac.uk
Contact: Steven J Hunter, MD 02890471883 steven.hunter@belfasttrust.hscni.net
United Kingdom
 
NCT01889810
QUB: B12/35; HSC: 12117MMcK-AS
No
Michelle McKinley, Queen's University, Belfast
Queen's University, Belfast
  • HSC Research & Development Division, Public Health Agency, Northern Ireland
  • The Metabolic Unit Research Fund, The Royal Hospitals, Belfast, Northern Ireland
  • NI Chest, Heart & Stroke
Principal Investigator: Michelle McKinley, PhD Queen's University, Belfast
Queen's University, Belfast
November 2013

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP