The effect of vitamin D supplementation on plasma leptin/adiponectin ratio in diabetic individuals with different haptoglobin phenotypes

AimThe present study was designed to evaluate the impact of high doses of vitamin D on plasma leptin/adiponectin ratio (LAR) and on glucose homeostasis parameters in diabetic individuals with different haptoglobin phenotypes. Materials and methodsIn a randomized, placebo-controlled study, 47 diabetic patients were assigned to two groups: group 1 received an oral supplementation of vitamin D daily at a dose of 1000 U/day and group 2 received matching placebo capsules. In addition, each group was divided into two subgroups by Hp phenotype: subgroup 1 included diabetic patients with the Hp 2-2 phenotype and subgroup 2 included non-Hp 2-2 patients. ResultsAfter 12 months, LAR decreased significantly from 3.6±2.5 to 2.3±1.5 (P=0.039) in patients with the Hp 2-2 phenotype and did not change significantly in non-Hp 2-2 diabetic patients receiving vitamin D. No change was detected in LAR in subgroups of patients receiving placebo. ConclusionHigh doses of vitamin D supplementation were associated with a decrease in LAR in diabetic patients with the Hp 2-2 phenotype.