Vitamin D supplementation as an adjuvant therapy for patients with T2DM: an 18-month prospective interventional study.
BACKGROUND
Vitamin D deficiency has been associated with impaired human insulin action, suggesting a role in the pathogenesis of diabetes mellitus type 2 (T2DM). In this prospective interventional study we investigated the effects of vitamin D3 supplementation on the metabolic profiles of Saudi T2DM subjects pre- and post-vitamin D supplementation over an 18-month period.


METHODS
T2DM Saudi subjects (men, N = 34: Age: 56.6 ± 8.7 yr, BMI, 29.1 ± 3.3 kg/m2; women, N = 58: Age: 51.2 ± 10.6 yr, BMI 34.3 ± 4.9 kg/m2;) were recruited and given 2000 IU vitamin D3 daily for 18 months. Anthropometrics and fasting blood were collected (0, 6, 12, 18 months) to monitor serum 25-hydroxyvitamin D using specific ELISA, and to determine metabolic profiles by standard methods.


RESULTS
In all subjects there was a significant increase in mean 25-hydroxyvitamin D levels from baseline (32.2 ± 1.5 nmol/L) to 18 months (54.7 ± 1.5 nmol/L; p < 0.001), as well as serum calcium (baseline = 2.3 ± 0.23 mmol/L vs. 18 months = 2.6 ± 0.1 mmol/L; p = 0.003). A significant decrease in LDL- (baseline = 4.4 ± 0.8 mmol/L vs. 18 months = 3.6 ± 0.8 mmol/L, p < 0.001] and total cholesterol (baseline = 5.4 ± 0.2 mmol/L vs. 18 months = 4.9 ± 0.3 mmol/L, p < 0.001) were noted, as well as a significant improvement in HOMA-β function (p = 0.002). Majority of the improvements elicited were more prominent in women than men.


CONCLUSIONS
In the Saudi T2DM population receiving oral Vitamin D3 supplementation (2000 IU/day), circulating 25-hydroxyvitamin D levels remained below normal 18 months after the onset of treatment. Yet, this "suboptimal" supplementation significantly improved lipid profile with a favorable change in HDL/LDL ratio, and HOMA-β function, which were more pronounced in T2DM females.
Biomarkers Research Program, Biochemistry Department, College of Science, King Saud University, PO Box, 2455, Riyadh, 11451, Kingdom of Saudi Arabia. aldaghri2011@gmail.com
Nasser M
NM
Al-Daghri
Khalid M
KM
Alkharfy
Abdulaziz
A
Al-Othman
Emad
E
El-Kholie
Osama
O
Moharram
Majed S
MS
Alokail
Yousef
Y
Al-Saleh
Shaun
S
Sabico
Sudhesh
S
Kumar
George P
GP
Chrousos
D000328:Adult; D000368:Aged; D002118:Calcium / Q000097:blood; D002762:Cholecalciferol / Q000627:therapeutic use*; D008078:Cholesterol, LDL / Q000097:blood; D003924:Diabetes Mellitus, Type 2 / Q000188:drug therapy*; D019587:Dietary Supplements; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012727:Sex Characteristics; D012737:Sex Factors; D014807:Vitamin D / Q000031:analogs & derivatives / Q000097:blood; D014808:Vitamin D Deficiency / Q000188:drug therapy
D008078:Cholesterol, LDL; D014807:Vitamin D; D002762:Cholecalciferol; C104450:25-hydroxyvitamin D; D002118:Calcium