Effect of large doses of parenteral vitamin D on glycaemic control and calcium/phosphate metabolism in patients with stable type 2 diabetes mellitus: a randomised, placebo-controlled, prospective pilot study

• Published in: Swiss medical weekly 2014-03, Vol.144 (1112), p.w13942-w13942
• Main Authors: Jehle, Sigrid, Lardi, Alessia, Felix, Barbara, Hulter, Henry N, Stettler, Christoph, Krapf, Reto
• Format: Article
• Language: English
• Subjects: Aged; Albuminuria - urine; Blood Pressure - drug effects; Calcitriol - blood; Calcium - blood; Calcium - urine; Cholecalciferol - administration & dosage; Diabetes mellitus; Diabetes Mellitus, Type 2 - drug therapy; Diabetes Mellitus, Type 2 - metabolism; Double-Blind Method; Female; FGF-23; Glycated Hemoglobin A - metabolism; Homeostasis; Humans; Insulin - metabolism; Insulin Resistance; insulin sensitivity; Male; Middle Aged; Parathyroid Hormone - blood; Phosphates - blood; Phosphates - urine; Pilot Projects; Prospective Studies; Vitamin D; Vitamins - administration & dosage
• ISSN: 1424-7860; 1424-3997
• DOI: 10.4414/smw.2014.13942

Vitamin D (D₃) status is reported to correlate negatively with insulin production and insulin sensitivity in patients with type 2 diabetes mellitus (T2DM). However, few placebo-controlled intervention data are available. We aimed to assess the effect of large doses of parenteral D3 on glycosylated haemoglobin (HbA(₁c)) and estimates of insulin action (homeostasis model assessment insulin resistance: HOMA-IR) in patients with stable T2DM. We performed a prospective, randomised, double-blind, placebo-controlled pilot study at a single university care setting in Switzerland. Fifty-five patients of both genders with T2DM of more than 10 years were enrolled and randomised to either 300,000 IU D₃ or placebo, intramuscularly. The primary endpoint was the intergroup difference in HbA(₁c) levels. Secondary endpoints were: changes in insulin sensitivity, albuminuria, calcium/phosphate metabolism, activity of the renin-aldosterone axis and changes in 24-hour ambulatory blood pressure values. After 6 months of D₃ supply, there was a significant intergroup difference in the change in HbA(₁c) levels (relative change [mean ± standard deviation] +2.9% ± 1.5% in the D₃ group vs +6.9% ± 2.1% the in placebo group, p = 0.041) as HOMA-IR decreased by 12.8% ± 5.6% in the D₃ group and increased by 10% ± 5.4% in the placebo group (intergroup difference, p = 0.032). Twenty-four-hour urinary albumin excretion decreased in the D₃ group from 200 ± 41 to 126 ± 39, p = 0.021). There was no significant intergroup difference for the other secondary endpoints. D₃ improved insulin sensitivity (based on HOMA-IR) and affected the course of HbA(₁c) positively compared with placebo in patients with T2DM.