Baseline Characteristics of the Vitamin D and Type 2 Diabetes (D2d) Study: A Contemporary Prediabetes Cohort That Will Inform Diabetes Prevention Efforts
Article
LeBlanc, Erin S., Pratley, Richard E., Dawson-Hughes, Bess, Staten, Myrlene A., Sheehan, Patricia R., Lewis, Michael R., Peters, Anne, Kim, Sun H., Chatterjee, Ranee, Aroda, Vanita R., Chadha, Chhavi, Neff, Lisa M., Brodsky, Irwin G., Rosen, Clifford, Desouza, Cyrus V., Foreyt, John P., Hsia, Daniel S., Johnson, Karen C., Raskin, Philip, Kashyap, Sangeeta R., O'Neil, Patrick, Phillips, Lawrence S., Rasouli, Neda, Liao, Emilia P., Robbins, David C., Pittas, Anastassios G., D2d Res Grp
funding text
The planning phase of D2d was funded by the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) through a multicenter clinical study implementation planning grant (U34) to Tufts Medical Center in Boston, MA (U34-DK-091958 to principal investigator A.G.P.). Planning was also supported in part by the Intramural Research Program of the NIDDK. The conduct of D2d is primarily supported by NIDDK and the Office of Dietary Supplements of the NIH through the multicenter clinical study cooperative agreement (U01-DK-098245 to principal investigator A.G.P.) to Tufts Medical Center, where the D2d Coordinating Center is based. The U01 grant mechanism establishes the NIDDK project scientist (M.A.S.) as a member of the D2d Research Group. The study also received secondary funding from the ADA (1-14-D2d-01). Educational materials are provided by the National Diabetes Education Program. The D2d investigators and the NIDDK project scientist were responsible for the design and conduct of the study; collection, management, analysis, and interpretation of data; preparation, review, and approval of the manuscript; and decision to submit the manuscript for publication. Under the terms of the cooperative agreement funding mechanism used by the NIH, representatives from the sponsoring NIDDK participated in the design and conduct of the study; interpretation of data; preparation, review, and approval of the manuscript; and the decision to submit the manuscript for publication.
abstract
OBJECTIVE To describe baseline characteristics of the Vitamin D and Type 2 Diabetes (D2d) study, the first large U.S. diabetes prevention clinical trial to apply current American Diabetes Association (ADA) criteria for prediabetes. RESEARCH DESIGN AND METHODS This is a multicenter (n = 22 sites), randomized, double-blind, placebo-controlled, primary prevention clinical trial testing effects of oral daily 4,000 IU cholecalciferol (D-3) compared with placebo on incident diabetes in U.S. adults at risk for diabetes. Eligible participants were at risk for diabetes, defined as not meeting criteria for diabetes but meeting at least two 2010 ADA glycemic criteria for prediabetes: fasting plasma glucose (FPG) 100-125 mg/dL, 2-h postload glucose (2hPG) after a 75-g oral glucose load 140-199 mg/dL, and/or a hemoglobin A(1c) (HbA(1c)) 5.7-6.4% (39-46 mmol/mol). RESULTS A total of 2,423 participants (45% of whom were women and 33% nonwhite) were randomized to cholecalciferol or placebo. Mean (SD) age was 59 (9.9) years and BMI 32 (4.5) kg/m(2). Thirty-five percent met all three prediabetes criteria, 49% met the FPG/HbA(1c) criteria only, 9.5% met the 2hPG/FPG criteria only, and 6.3% met the 2hPG/HbA(1c) criteria only. Black participants had the highest mean HbA(1c) and lowest FPG concentration compared with white, Asian, and other races (P < 0.01); 2hPG concentration did not differ among racial groups. When compared with previous prediabetes cohorts, the D2d cohort had lower mean 2hPG concentration but similar HbA(1c) and FPG concentrations. CONCLUSIONS D2d will establish whether vitamin D supplementation lowers risk of diabetes and will inform about the natural history of prediabetes per contemporary ADA criteria.