Effect of therapeutic dose of vitamin D on serum adiponectin and glycemia in vitamin D-insufficient or deficient type 2 diabetic Patients

Abstract EN

Background : Lower vitamin D status has been reported in diabetic patients.

Serum 25-hydroxyvitamin D and adiponectin were inversely associated with type 2 diabetes and insulin resistance.

Vitamin D may involve in regulation of the adiponectin levels, which is directly related to insulin sensitivity. Objectives : The aim of this study was to investigate the effect of therapeutic dose of vitamin D on serum adiponectin and insulin resistance in vitamin D-insufficient or deficient type 2 diabetic patients. Materials and Methods : This double-blind, randomized, clinical trial was conducted on 81 type 2 diabetic patients with vitamin D level of 10-30 ng/mL.

Intervention was 50000 IU vitamin D or placebo once a week for 8 weeks.

At the beginning and end of the study, blood samples were collected after 12 hours of fasting and serum glucose, insulin, 25-hydroxyvitamin D, and adiponectin were measured.

Insulin resistance was calculated by homeostasis model assessment (HOMA-IR). Results : After 8-week intervention, serum 25-hydroxyvitamin D significantly increased and reached the normal levels in patients receiving vitamin D (P < 0.001) and the levels of fasting serum glucose, insulin, and HOMA-IR were significantly decreased (P = 0.04, 0.02 and 0.007, respectively).

No significant changes were observed in these levels in the placebo group.

Significant differences were observed in mean changes in the above-mentioned variables between the two groups (P = 0.01, 0.04 and 0.006, respectively).

No significant changes were found in serum adiponectin in the vitamin D and placebo groups (P = 0.83). Conclusions : Therapeutic dose of vitamin D can improve vitamin D status and glycemic indicators.

But it seems that an 8-week intervention period was not sufficient to reveal the possible effects of vitamin D on serum adiponectin levels.