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

NCT ID: NCT01889810

Last Updated: 2023-05-06

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 81 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2013-08-31
• Study Completion Date: 2016-06-30

Brief Summary

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.

Conditions

Sub-optimal Vitamin D Status; Pre-diabetes; Insulin Resistance

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: PREVENTION
• Blinding Strategy: QUADRUPLE

Study Groups

Vitamin D3 supplementation

Patients will take 3000IU (75 µg) Vitamin D3 supplementation per day for a period of 26 weeks.

Group Type: ACTIVE_COMPARATOR

Vitamin D3 supplementation

Intervention Type: DIETARY_SUPPLEMENT

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.

Placebo

Placebo group

Group Type: PLACEBO_COMPARATOR

Vitamin D3 supplementation

Intervention Type: DIETARY_SUPPLEMENT

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.

Interventions

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.

Intervention Type: DIETARY_SUPPLEMENT

Eligibility Criteria

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)

• Minimum Eligible Age: 18 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

Health and Social Care Research and Development , Northern Ireland

OTHER_GOV

Sponsor Role: collaborator

Royal Victoria Hospital, Belfast

OTHER

Sponsor Role: collaborator

Northern Ireland Chest Heart and Stroke

OTHER

Sponsor Role: collaborator

Queen's University, Belfast

OTHER

Sponsor Role: lead

Responsible Party

Michelle McKinley

Senior Lecturer, Nutrition & Metabolism Research Group, Centre for Public Health

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Michelle McKinley, PhD

Role: PRINCIPAL_INVESTIGATOR

Queen's University, Belfast

Locations

Queen's University, Belfast

Belfast, Northern Ireland, United Kingdom

Countries

United Kingdom

References

Wallace HJ, Holmes L, Ennis CN, Cardwell CR, Woodside JV, Young IS, Bell PM, Hunter SJ, McKinley MC. Effect of vitamin D3 supplementation on insulin resistance and beta-cell function in prediabetes: a double-blind, randomized, placebo-controlled trial. Am J Clin Nutr. 2019 Nov 1;110(5):1138-1147. doi: 10.1093/ajcn/nqz171.

Reference Type: BACKGROUND

PMID: 31559433 (View on PubMed)

Other Identifiers

QUB: B12/35; HSC: 12117MMcK-AS

Identifier Type: -

Identifier Source: org_study_id