Effects of vitamin D2 or D3 supplementation on glycaemic control and cardiometabolic risk among people at risk of type 2 diabetes: results of a randomized double‐blind placebo‐controlled trial. Issue 4 (4th February 2016)

• Record Type: Journal Article
• Authors: Forouhi, N. G.; Menon, R. K.; Sharp, S. J.; Mannan, N.; Timms, P. M.; Martineau, A. R.; Rickard, A. P.; Boucher, B. J.; Chowdhury, T. A.; Griffiths, C. J.; Greenwald, S. E.; Griffin, S. J.; Hitman, G. A.
• Is Part Of: Diabetes, obesity & metabolism. Volume 18:Issue 4(2016)
• Page Start: 392
• Page End: 400
• Publication Date: 2016-02-04
• Subjects: intervention -- placebo -- pulse wave velocity -- randomized -- trial -- type 2 diabetes -- vitamin D2 -- vitamin D3; Diabetes -- Periodicals; Obesity -- Periodicals; Metabolism -- Disorders -- Periodicals; Clinical pharmacology -- Periodicals; 616.462
• DOI: 10.1111/dom.12625
• Languages: English
• ISSNs: 1462-8902

Abstract

Abstract : Aims: To investigate the effect of short‐term vitamin D supplementation on cardiometabolic outcomes among individuals with an elevated risk of diabetes. Methods: In a double‐blind placebo‐controlled randomized trial, 340 adults who had an elevated risk of type 2 diabetes (non‐diabetic hyperglycaemia or positive diabetes risk score) were randomized to either placebo, 100 000 IU vitamin D2 (ergocalciferol) or 100 000 IU vitamin D3 (cholecalciferol), orally administered monthly for 4 months. The primary outcome was change in glycated haemoglobin (HbA1c) between baseline and 4 months, adjusted for baseline. Secondary outcomes included: blood pressure; lipid levels; apolipoprotein levels; C‐reactive protein levels; pulse wave velocity (PWV); anthropometric measures; and safety of the supplementation. Results: The mean [standard deviation (s.d.)] 25‐hydroxyvitamin D [25(OH)D]2 concentration increased from 5.2 (4.1) to 53.9 (18.5) nmol/l in the D2 group, and the mean (s.d.) 25(OH)D3 concentration increased from 45.8 (22.6) to 83.8 (22.7) nmol/l in the D3 group. There was no effect of vitamin D supplementation on HbA1c: D2 versus placebo: −0.05% [95% confidence interval (CI) −0.11, 0.02] or −0.51 mmol/mol (95% CI −1.16, 0.14; p = 0.13); D3 versus placebo: 0.02% (95% CI −0.04, 0.08) or 0.19 mmol/mol (95% CI −0.46, 0.83; p = 0.57). There were no clinically meaningful effects on secondary outcomes, except PWV [D2 versus placebo: −0.68 m/s (95% CI −1.31, −0.05); D3 versus placebo −0.73 m/s (95% CI −1.42, −0.03)]. No important safety issues were identified. Conclusions: Short‐term supplementation with vitamin D2 or D3 had no effect on HbA1c. The modest reduction in PWV with both D2 and D3 relative to placebo suggests that vitamin D supplementation has a beneficial effect on arterial stiffness.