Can Calcium and Vitamin D reduce diabetes risk in people at high risk?

Phase 4

Recruiting

• Conditions: Pre-diabetes (impaired fasting glucose or impaired glucose tolerance); Obesity; Vitamin D deficiency; Metabolic and Endocrine - Diabetes

• Registration Number: ACTRN12609000043235
• Lead Sponsor: Professor Peter Ebeling

Brief Summary

Not available

Detailed Description

Not available

Study Timeline

• Results First Posted: 1900-01-01
• Study Start: 2009-01-20
• Last Update Posted: 13 January 2020

Recruitment & Eligibility

• Status: Recruiting
• Sex: All
• Target Recruitment: 160

Inclusion Criteria

Vitamin D deficiency; overweight or obese as defined by a body-mass index (BMI) between 25-35 kg/m2; impaired fasting glucose or impaired glucose tolerance confirmed with a 75g 2h oral glucose tolerance test (OGTT).

Exclusion Criteria

Pregnancy; Breast-feeding; Renal insufficiency; Cirrhosis; Malabsorption; Hypercalcemia; Hypercalciuria; History of nephrolithiasis; Previous non-traumatic fractures; Active or chronic inflammatory disease;Medications known to affect vitamin D, calcium or bone metabolism over the last 3 months; Pharmacological treatment for obesity or medications known to alter glucose metabolism over the last 3 months; Bariatric surgery planned in the next six months or patients who had undergone bariatric surgery in the past; Commenced regular physical activity (more than 3 times/week) in the last 3 months; More than a 5% change in weight in the last 3 months.

Study & Design

• Study Type: Interventional
• Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
Determine if calcium and vitamin D reduces insulin resistance assessed by homeostasis model assessment of insulin resistance(HOMA-IR)[Baseline and 6 months];Determine if calcium and vitamin D improve glucose-stimulated insulin secretion(insulinogenic index and deconvolution analysis of C-peptide after a glucose load)[Baseline and 6 months];Determine if calcium and vitamin D improve beta-cell function (disposition index)[Baseline and 6 months]

Secondary Outcome Measures

Name	Time	Method
Determine if vitamin D reduces biochemical markers of inflammation associated with increased cardiovascular risk (serum high-sensitive C-reactive protein, fibrinogen, Interleukin-6, Tumor necrosis factor alpha)[Baseline and 6 months];Determine if vitamin D reduces gamma-carboxylation of osteocalcin and increases adiponectin by comparing serum adiponectin levels and the decarboxylated form of osteocalcin before and after treatment[Baseline and 6 months];Determine if calcium and vitamin D improve blood pressure.[Blood pressure: 0, 2 and 6 months];Determine whether vitamin D requirements are influenced by fat mass assessed by dual X-Ray absorptiometry (DXA)[Baseline];Determine if calcium and vitamin D improve the lipid profile (serum total cholesterol, HDL-cholesterol, LDL-cholesterol, triglycerides).[Baseline and 6 months]