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ARS Home » Northeast Area » Boston, Massachusetts » Jean Mayer Human Nutrition Research Center On Aging » Research » Publications at this Location » Publication #396530
Research Project: Nutrient Metabolism and Musculoskeletal Health in Older Adults

Location: Jean Mayer Human Nutrition Research Center On Aging

Title: Vitamin D and risk for type 2 diabetes in people with prediabetes: a systematic review and meta-analysis of individual participant data from 3 randomized clinical trials

Author
item PITTAS, ANASTASSIOS - Tufts Medical Center
item KAWAHARA, TETSUYA - Kokura Medical Association Health Testing Center
item JORDE, ROLF - The Arctic University Of Norway (UIT)
item DAWSON-HUGHES, BESS - Jean Mayer Human Nutrition Research Center On Aging At Tufts University
item VICKERY, ELLEN - Tufts Medical Center
item ANGELLOTTI, EDITH - Takeda Pharmaceutical
item NELSON, JASON - Tufts Medical Center
item TRIKALINOS, THOMAS - Brown University
item BALK, ETHAN - Brown University

Submitted to: Annals of Internal Medicine
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/22/2022
Publication Date: 2/7/2023
Citation: Pittas, A.G., Kawahara, T., Jorde, R., Dawson-Hughes, B., Vickery, E.M., Angellotti, E., Nelson, J., Trikalinos, T.A., Balk, E.M. 2023. Vitamin D and risk for type 2 diabetes in people with prediabetes: a systematic review and meta-analysis of individual participant data from 3 randomized clinical trials. Annals of Internal Medicine. https://doi.org/10.7326/M22-3018.
DOI: https://doi.org/10.7326/M22-3018

Interpretive Summary: Higher blood levels of the 25-hydroxyvitamin D have been associated with lower risk of type 2 diabetes (T2D) but clinical trials have not conclusively shown that vitamin D supplementation prevents T2D. We combined data from 3 large clinical trials to determine whether treatment with vitamin D lowered risk of T2D in adults with prediabetes. These trials, conducted in the USA, Norway, and Japan tested vitamin D3 doses of 4000 IU/day, 20,000 IU/week, and 0.75 microg/day, respectively, for a period of 3 years each. In the combined dataset of 4,190 participants, treatment with vitamin D significantly lowered risk of developing T2D by 12%, when compared with placebo. The treatment did not increase risk of adverse events. In conclusion, vitamin D supplementation was safe and effective in lowering risk of developing diabetes.

Technical Abstract: Background: The role of vitamin D in people who are at risk for type 2 diabetes remains unclear. Purpose: To evaluate whether administration of vitamin D decreases risk for diabetes among people with prediabetes. Data Sources: PubMed, Embase, and ClinicalTrials.gov from database inception through 9 December 2022. Study Selection: Eligible trials that were specifically designed and conducted to test the effects of oral vitamin D versus placebo on new-onset diabetes in adults with prediabetes. Data Extraction: The primary outcome was time to event for new-onset diabetes. Secondary outcomes were regression to normal glucose regulation and adverse events. Prespecified analyses (both unadjusted and adjusted for key baseline variables) were conducted according to the intention-to-treat principle. Data Synthesis: Three randomized trials were included, which tested cholecalciferol, 20 000 IU (500 mcg) weekly; cholecalciferol, 4000 IU (100 mcg) daily; or eldecalcitol, 0.75 mcg daily, versus matching placebos. Trials were at low risk of bias. Vitamin D reduced risk for diabetes by 15% (hazard ratio, 0.85 [95% CI, 0.75 to 0.96]) in adjusted analyses, with a 3-year absolute risk reduction of 3.3% (CI, 0.6% to 6.0%). The effect of vitamin D did not differ in prespecified subgroups. Among participants assigned to the vitamin D group who maintained an intratrial mean serum 25-hydroxyvitamin D level of at least 125 nmol/L (