The Differential Role of Vitamin D in Type 2 Diabetes Management and Control in Minority Populations
Vitamin D deficiency is associated with incidence of type 2 diabetes (T2DM) as well as poor glycemic control among T2DM patients, yet comparative studies of its association among ethnic minority populations are scarce. Using baseline data from a behavioral intervention study of Korean Americans (KAs) with T2DM (N = 250 KAs) and the NHANES data set, we explored differential roles of vitamin D on HbA1C level or T2DM control in several racial groups. Significantly more KAs (55.2%) were vitamin D-deficient (U.S. average, 37.8%). Both common and unique correlates of vitamin D deficiency in minority populations were identified, including significant associations between Vitamin D and HbA1C in both non-diabetic and diabetic populations. Future studies are warranted to explain the causal mechanism of the effect of vitamin D and glycemic control as well as to examine contextual factors associated with vitamin D deficiency in certain minority groups.
Clinical Trials Registry: Identifier NCT01264796
KeywordsVitamin D Type 2 diabetes Self-help Korean Americans NHANES
The study was supported by a grant from the National Institute of Diabetes and Digestive and Kidney Diseases (R18DK083936), with material support from LifeScan, including devices (OneTouch glucometers, OneTouch UltraSoft® test strips, and OneTouch UltraSoft lancets) for study participants. In addition, the Johns Hopkins ICTR supported the cost of blood serum lab tests. The authors are grateful for substantial editorial assistance provided by Dr. Deborah McClellan. Editorial support with manuscript development was also provided by the Cain Center for Nursing Research and the Center for Transdisciplinary Collaborative Research in Self-management Science (P30, NR015335) at The University of Texas at Austin School of Nursing. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health or other supporters.
Compliance with Ethical Standards
Conflict of interest
All authors declare that they have no conflict of interest.
All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards.
Human Participant Protection
The research protocol was approved by the Johns Hopkins Medical Institutions Institutional Review Board, and written consent was obtained from all study participants.
Informed consent was obtained from all individual participants included in the study.
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