VITAL: Vitamin D, omega-3 do not preserve kidney function in type 2 diabetes
WASHINGTON — Results from an ancillary study to the Vitamin D and Omega-3 Trial, known as VITAL, demonstrated no difference in eGFR reduction between patients with type 2 diabetes who were assigned to either supplementation or placebo. Data were presented at ASN Kidney Week and simultaneously published in JAMA.
“To effectively treat the problem [of diabetes and kidney disease], my opinion is that we need interventions across the whole spectrum of this pathogenesis from preventing diabetes itself, preventing [chronic kidney disease] CKD in diabetes, preventing its progression to ESKD and then treating patients with ESKD better,” Ian H. de Boer, MD, MS, of the division of nephrology in the department of medicine at the University of Washington in Seattle, said during a press conference here. “This is a trial that asks the question of whether we can use widely available, inexpensive and relatively safe supplements to prevent CKD or prevent its progression early in the course of type 2 diabetes. Both vitamin D and omega-3 fatty acids have good plausibility for benefits early in diabetes, both in experimental animal models, observational studies in human populations and short-term preliminary clinical trials.”
To determine whether either supplement prevents the development or progression of CKD, researchers randomized 934 adults with type 2 diabetes to receive vitamin D and omega-3 fatty acids; vitamin D and placebo; placebo and omega-3 fatty acids; or two placebos for 5 years. Vitamin D and omega-3 were given in doses of 2000 IU per day and 1 gram per day, respectively.
Compared to eGFR at baseline (mean, 85.8 mL/min/1.73m2), researchers observed a reduction of 12.3 mL/min/1.73m2 in participants taking vitamin D vs. a reduction of 13.1 mL/min/1.73m2 in those taking placebo after 5 years. Similarly, participants taking omega-3 fatty acids experienced an eGFR reduction of 12.2 mL/min/1.73m2 vs. 13.1 mL/min/1.73m2 with placebo. Researchers also observed no significant differences in change in albuminuria between the two groups.
The most common adverse effects were kidney stones (occurring in 32 participants receiving vitamin D vs. 26 on placebo) and gastrointestinal bleeding (in 28 participants receiving omega-3 vs. 17 receiving placebo).
“We performed a number of sensitivity and secondary analyses that were also null both for vitamin D and for omega 3-fatty acids,” de Boer said. “The results do not support routine vitamin D or omega-3 fatty acids supplementation to prevent CKD in type 2 diabetes.” – by Melissa J. Webb
de Boer IH, et al. Abstract FR-OR138. Presented at: ASN Kidney Week; Nov. 7-10, 2019; Washington D.C.
Disclosure: de Boer reports receipt of consulting fees from Boehringer Ingelheim and Ironwood; and equipment and supplies for research from Medtronic and Abbott.