Circulating Vitamin D Metabolites and Subclinical Atherosclerosis in Type 1 Diabetes

  1. and Complications Study (DCCT/EDIC) Research Group
  1. 1University of Washington, Seattle, Washington
  2. 2The George Washington University, Washington, D.C.
  3. 3Northwestern University, Chicago, Illinois
  4. 4University of Minnesota, Minneapolis, Minnesota
  5. 5University of Toronto, Toronto, Ontario, Canada
  1. Corresponding author: Michael C. Sachs, sachsmc{at}u.washington.edu.

Abstract

OBJECTIVE People with type 1 diabetes are at high risk of premature atherosclerosis. Existing evidence suggests that impaired vitamin D metabolism may contribute to the development of atherosclerosis. We tested associations of circulating vitamin D metabolite concentrations with subclinical atherosclerosis among 1,193 participants with type 1 diabetes in the DCCT/EDIC study.

RESEARCH DESIGN AND METHODS We measured plasma concentrations of 25-hydroxyvitamin D [25(OH)D], 1,25-dihydroxyvitamin D, and 24,25-dihydroxyvitamin D by mass spectrometry at the end of the DCCT. In a staggered cross-sectional design, we tested associations with coronary artery calcium (CAC), measured by computed tomography a median of 10 years later, and with common and internal carotid intima-media thickness (IMT), measured by B-mode ultrasonography on two occasions a median of 4 years later and a median of 10 years later. We hypothesized that lower concentrations of each vitamin D metabolite would be associated with increased risk of CAC and greater carotid IMT.

RESULTS At the time metabolites were measured, mean age was 32.4 years and mean duration of diabetes was 7.5 years. The prevalence and severity of CAC tended to be lower—not higher—with lower concentrations of each vitamin D metabolite. For instance, in a fully adjusted multinomial logistic model, a 25 nmol/L lower 25-hydroxyvitamin D was associated with a 0.8-fold decrease in the odds of having higher CAC (95% CI 0.68–0.96, P = 0.01). No vitamin D metabolite was associated with either common or internal mean IMT.

CONCLUSIONS We did not find evidence linking impaired vitamin D metabolism with increased subclinical atherosclerosis in type 1 diabetes.

  • Received October 3, 2012.
  • Accepted January 17, 2013.

Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered. See http://creativecommons.org/licenses/by-nc-nd/3.0/ for details.

This Article

  1. Diabetes Care
  1. Supplementary Data
  2. All Versions of this Article:
    1. dc12-2020v1
    2. 36/8/2423 most recent