Abstract: FR-OR138
Effects of Vitamin D and Omega-3 Fatty Acid Supplementation on Kidney Function and Damage in Type 2 Diabetes
Session Information
- High-Impact Clinical Trials
November 08, 2019 | Location: Ballroom C, Walter E. Washington Convention Center
Abstract Time: 03:45 PM - 04:00 PM
Category: Diabetic Kidney Disease
- No subcategory defined
Authors
- de Boer, Ian H., Division of Nephrology and Kidney Research Institute, University of Washington, Seattle, Washington, United States
- Zelnick, Leila R., Kidney Research Institute, Seattle, Washington, United States
- Hoofnagle, Andrew N., University of Washington, Seattle, Washington, United States
- Thadhani, Ravi I., Cedars-Sinai, Los Angeles, California, United States
- Manson, Joann E., Brigham and Women's Hospital, Harvard, Boston, Massachusetts, United States
Group or Team Name
- VITAL-DKD Research Group
Background
Vitamin D and omega-3 fatty acid supplements are readily available and safe interventions that may help prevent the development and progression of diabetic kidney disease. Preclinical and observational studies suggest that vitamin D suppresses the renin-angiotensin system, reduces renal inflammation and fibrosis, and exerts direct pro-survival effects on podocytes, while omega-3 fatty acids have potentially beneficial anti-inflammatory, antithrombotic, and vascular properties.
Methods
We performed a randomized clinical trial of 1,312 adults with type 2 diabetes to test whether supplementation with vitamin D3 or omega-3 fatty acids for five years prevents the development or progression of CKD. The study was completed as an ancillary study to the VITamin D and OmegA-3 TriaL (VITAL). In a 2-by-2 factorial design, participants were randomly assigned to vitamin D3 (2000 IU daily) or placebo and to omega-3 fatty acids (eicospentaenoic acid and docosahexaenoic acid, 1 g daily) or placebo. The primary outcome was change in glomerular filtration rate estimated from serum creatinine and cystatin C (eGFR) from baseline to year 5.
Results
Baseline mean age was 67.6 (SD 6.9) years, 46% of participants were women, and 31% were racial or ethnic minorities. Baseline mean (SD) eGFR was 85.8 (22.1) mL/min/1.73m2, and mean change in eGFR from baseline to year 5 was -12.7 (SD 14.6) mL/min/1.73m2. There was no significant difference in change in eGFR comparing vitamin D3 to placebo (difference in change 0.8 (95% CI -0.8, 2.5) mL/min/1.73m2) or omega-3 fatty acids to placebo (difference in change 0.8 (95% CI -0.8, 2.4) mL/min/1.73m2). Null results were robust in analyses restricted to participants with complete data or to participants who were highly adherent to study medications. No significant difference was observed in secondary outcomes, including change in eGFR after 2 years of treatment, a composite outcome of loss of eGFR ≥40% from baseline or kidney failure (N=85 events), and change in urine albumin excretion.
Conclusion
Neither vitamin D nor omega-3 fatty acid supplementation reduced the development or progression of kidney disease among adults with type 2 diabetes.
Funding
- NIDDK Support