The effect of high-dose vitamin D supplementation on insulin resistance and arterial stiffness in patients with type 2 diabetes.
10.3904/kjim.2014.29.5.620
- Author:
Ohk Hyun RYU
1
;
Wankyo CHUNG
;
Sungwha LEE
;
Kyung Soon HONG
;
Moon Gi CHOI
;
Hyung Joon YOO
Author Information
1. Division of Endocrinology and Metabolism, Department of Internal Medicine, Hallym University College of Medicine, Chuncheon, Korea. mgchoi@hallym.or.kr
- Publication Type:Original Article ; Randomized Controlled Trial ; Research Support, Non-U.S. Gov't
- Keywords:
Diabetes mellitus, type 2;
Insulin resistance;
Vitamin D deficiency;
Vascular stiffness
- MeSH:
Calcium, Dietary/administration & dosage;
Cholecalciferol/*administration & dosage;
Diabetes Mellitus, Type 2/complications/*drug therapy/physiopathology;
Double-Blind Method;
Female;
Humans;
*Insulin Resistance;
Male;
Middle Aged;
Prospective Studies;
Vascular Stiffness/*drug effects;
Vitamin D/analogs & derivatives/blood;
Vitamin D Deficiency/blood/complications/drug therapy
- From:The Korean Journal of Internal Medicine
2014;29(5):620-629
- CountryRepublic of Korea
- Language:English
-
Abstract:
BACKGROUND/AIMS: Recent epidemiological studies revealed a striking inverse relationship between vitamin D levels, glucose intolerance/insulin resistance (IR), and cardiovascular disease. However, few interventional studies have evaluated the effect of vitamin D supplementation on cardiovascular risk, such as IR and arterial stiffness, in diabetes. We investigated the role of vitamin D supplementation on cardiovascular risk in type 2 diabetes patients, including metabolic parameters, IR, and arterial stiffness. METHODS: We enrolled patients who were taking antidiabetic medications or managed their diabetes using lifestyle changes. We excluded patients who were taking vitamin D or calcium supplements. We randomized participants into the vitamin D group (cholecalciferol 2,000 IU/day + calcium 200 mg/day, n = 40) or the placebo group (calcium 200 mg/day, n = 41). We compared their IR (homeostasis model of assessment [HOMA]-IR) and arterial stiffness (brachial-ankle pulse wave velocity and radial augmentation index) before and after 24 weeks of intervention. RESULTS: The baseline characteristics of the two groups were similar. A total of 62 participants (placebo, 30; vitamin D, 32) completed the study protocol. At the end of the study period, the 25-hydroxyvitamin D [25(OH)D] levels were significantly higher in the vitamin D group than in the placebo group (35.4 +/- 8.5 ng/mL vs. 18.4 +/- 7.3 ng/mL, p < 0.001). There was no difference in HOMA-IR or changes in arterial stiffness (placebo, 21, vitamin D, 24) between the groups. CONCLUSIONS: Our data suggest that high-dose vitamin D supplementation might be effective in terms of elevating 25(OH)D levels. However, we identified no beneficial effects on cardiovascular risk in type 2 diabetes, including IR and arterial stiffness.
