Author(s)

Ghada M. El-Sagheer¹, Asmaa Kasem¹, Iglal M. Shawky², Ahmed Abdel-Fadeel³

¹Diabetes & Endocrinology Unit, Internal Medicine Department, Minia University Hospital, Minia University, El-Minia, Egypt.
²Internal Medicine Department, Minia University Hospital, Minia University, El-Minia, Egypt.
³Clinical Pathology Department, Minia University Hospital, Minia University, El-Minia, Egypt.

Background: Although recent meta-analyses indicates a consistent significant inverse relation of serum 25 (OH) D and the prevalence of gestational diabetes mellitus (GDM), the mechanism is unclear and conflicting opinions continue to be reported. Objectives: The objectives are: 1) comparison of vitamin D status in diabetic and non-diabetic pregnant women; 2) trying to determine the level of vitamin D associated with GDM, and its sensitivity and specificity; 3) determination of the relation of hypovitaminosis D with insulin resistance. Subjects and Methods: One hundred consecutive pregnant women (<28 weeks gestational period) from the attendants of the out-patient clinic at our hospital were diagnosed for GDM by glucose tolerance test (GTT) (75 g 2 h). Among them, 40 patients met the inclusion criteria for this study (group I). As a comparative group, another 40 pregnant ladies were included, 20 of them (group II) had pre-gestational type II DM, and the other 20 (group III) had normal glucose tolerance (NGT) as a control. For all the participants, we estimated fasting blood glucose, fasting serum insulin, homeostasis model assessment of (HOMA-IR and HOMA-B), quantitative insulin sensitivity check index (QUICKI), and serum 25-OH vit D. The ROC curve analysis was used to determine the optimal threshold value of vit D in relation to DM. Results: Compared to the control group, the diabetic patients showed a statistically significant increase in the levels of fasting glucose, 1-hour postprandial glucose, 2-hour post prandial glucose, fasting insulin, and HOMA-IR, (P=0.000 for all). None of the diabetic patients showed optimal vit D level. Vit D insuficiency (10 - 29 ng/ml) was found in 32.5% of patients in group I, 55% in group II, and 50% in group III. Vit D deficiency (<10 ng/ml) was found in 67.5% of patients in group I, 45% in group II, and 0% in group III. Significant negative correlation was found for vit D with fasting insulin and FBS. The AUC for 25 OH vit D was 97%, CI was 95% and p-value was 0.0001. The sensitivity, specificity, and positive and negative predictive values of 25 OH vit D in GDM versus control persons were 97%, 90%, 95.1%, 94.7% respectively at a cut-off level <22 ng/ml. Conclusions: Although it might seem premature to draw a sharp relation between hypovitaminosis D and GDM, this study showed the importance of vit D in GDM, the need for supplementation below 22 ng/ml, and the role of hypovitaminosis D in increasing insulin resistance. Further randomized studies with vit D supplementation are recommended.

Gestational Diabetes Mellitus, Glucose Intolerance, Vitamin D

El-Sagheer, G. , Kasem, A. , Shawky, I. and Abdel-Fadeel, A. (2016) Vitamin D Deficiency and Gestational Diabetes Mellitus in Egyptian Women. Open Journal of Endocrine and Metabolic Diseases, 6, 109-119. doi: 10.4236/ojemd.2016.62015.