Randomised Controlled Trial of Vitamin D3 in Diabetic Kidney Disease

This study will assess the effects of vitamin D3 supplementation (cholecalciferol; 2000 IU daily) on serum calcium levels, circulating vitamin D levels, and markers of kidney disease and cardiovascular risk among people with diabetes mellitus and early kidney disease. Eligibility criteria include type 2 diabetes and stage 1-2 chronic kidney disease, defined by a urine albumin-creatinine ratio 30-300 mg/g and an estimated glomerular filtration rate ≥ 60 mL/min. Participants will be randomly assigned to treatment with vitamin D3 or placebo, each taken by mouth once daily for a study duration of one year. Study medications will be added to standard treatment, including an angiotensin converting enzyme inhibitor and/or angiotensin II receptor blocker. We hypothesise that vitamin D3, compared with placebo: Is well-tolerated and safe among people with diabetes and kidney disease;Results in adequate attained circulating vitamin D levels; andPositively affects markers of kidney disease and cardiovascular risk.

Official Title

Randomised Controlled Trial of Vitamin D3 in Diabetic Kidney Disease.

Conditions

• Diabetes Mellitus
• Chronic Kidney Disease
• Diabetic Kidney Disease

Study Type

Interventional

Study Design

Treatment, Randomised, Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor), Placebo Control, Parallel Assignment.

Further Details

Primary Outcome Measures:

• Change in urine albumin excretion
  [Time Frame: One year]
  [Designated as safety issue: No]

Secondary Outcome Measures:

• Change in serum calcium concentration 
  [Time Frame: 3 months – 1 year]
  [Designated as safety issue: Yes]
• Change in serum 25-hydroxyvitamin D concentration
  [Time Frame: 3 months – 1 year] 
  [Designated as safety issue: No]
• Change in 24-hour ambulatory blood pressure
  [Time Frame: 3 months – 1 year][Designated as safety issue: No]
• Change in plasma lipids and lipoproteins
  [Time Frame: 3 months – 1 year]
  [Designated as safety issue: No]
• Change in circulating inflammatory proteins
  [Time Frame: 3 months – 1 year]
  [Designated as safety issue: No]
• Changes in circulating markers of mineral metabolism and insulin sensitivity
  [Time Frame: 3 months – 1 year]
  [Designated as safety issue: No]

Study Start

December 2007

Eligibility & Criteria

• Ages Eligible for Study: 18 Years and older
• Genders Eligible for Study: Both
• Accepts Healthy Volunteers: No

Inclusion Criteria:

• Clinical diagnosis of type 2 diabetes mellitus
• Urine albumin-creatinine ratio 30-300 mg/g
• Estimated glomerular filtration rate greater than or equal to 60 mL/min
• Treatment with angiotensin converting enzyme inhibitor and/or angiotensin II receptor blocker for greater than or equal to 6 months, with a stable dose for greater than or equal to 3 months
• Blood pressure less than 140/90 (assessed while taking medications)
• Hemoglobin A1c less than 9% (assessed while taking medications)

Exclusion Criteria:

• Prior dialysis or kidney transplantation
• Known cause of albuminuria other than diabetes
• Planning to leave the area within 12 months
• Life expectancy less than 12 months
• Participation in another clinical trial within 6 months
• Osteoporosis or other established indication for vitamin D therapy
• Vitamin D3 supplement intake greater than 400 IU/day at screening visit
• History of nephrolithiasis
• Serum calcium greater than 10.2 mg/dL
• Dementia, not fluent in English, or unable to provide informed consent without proxy respondent
• Incontinent of urine
• Failure to take greater than or equal to 80% of placebo pills during study run-in 

Total Enrolment

Contact Details

Ian H de Boer, MD, MS     
(206) 616-5403     
deboer@u.washington.edu 

Location:

University of Washington
Seattle, Washington
United States, 98195