Effects of Parenteral Vitamin D on the Biomarkers of the Endothelial Function in Patients with Type 2 Diabetes and Ischemic Heart Disease: A Randomized Clinical Trial

Vitamin d deficiency is associated with cardiovascular and metabolic diseases. cardiovascular diseases, in turn, are responsible for mortality of patients with type 2 diabetes (t2d). we investigated whether a single parenteral dose of 25(oh) vit d could improve the endothelial function in t2d patients with ischemic heart disease. a randomized, placebo- controlled, and double-blind trial was performed on 112 patients randomly divided into vitamin d (n = 55) and placebo (n = 57) groups. a randomization table was used to administer a single dose of either vitamin d (300000 iu) or a matching placebo, intramuscularly. the levels of 25(oh) vit d, intercellular adhesion molecule 1 (icam-1), and vascular cell adhesion molecule 1 (vcam-1) were measured at baseline and at 8 weeks. in the supplemented group, the level of serum 25(oh) vit d was increased significantly (29.6 ± 20.8 vs. 44.5 ± 19.2 ng/ml; p < 0.05), whereas no changes were observed in the placebo group. within the supplemented group, before and after vitamin d intervention no significant changes in the levels of icam- 1 and vcam-1 were observed. the marginal means of the outcome variables (icam-1, vcam-1, and 25(oh) vit d) were compared between the groups using ancova, adjusted for the baseline of each variable itself: no significant difference was seen in the markers of the endothelial function. a single parenteral dose of vitamin d in t2d patients with ischemic heart disease failed to show improvement in endothelial function.