Frequency of Vitamin D deficiency in pregnant diabetics at Baskent University Hospital, Istanbul

The Association between Maternal Serum Vitamin D Levels and Gestational Diabetes Mellitus among Filipino Patients: A Cross-Sectional Study

Objectives

To determine the association between low maternal serum vitamin D and gestational diabetes mellitus (GDM) among Filipino women in St. Luke’s Medical Center, Quezon City.

Methodology

A cross-sectional study involving pregnant women at outpatient clinics in a tertiary hospital in the Philippines. Simultaneous testing for fasting blood sugar, 75g oral glucose tolerance test and serum vitamin D was done. Participants were classified as GDM versus non-GDM, and normal versus low serum vitamin D. Univariate and multivariate statistics were done to determine relationship between vitamin D and GDM.

Results

Of 211 included women, 198 (93.8%) had low vitamin D levels, and 56 (26.5%) had GDM. Vitamin D was significantly higher in the GDM group (21.0±8.1 vs 18.8±5.3 ng/mL, p=0.0189). The proportion of women with low vitamin D levels was significantly higher among those without GDM (96.1% vs 87.5%, OR=0.28, p=0.029]. After adjusting for age, parity, history of GDM and pre-pregnancy BMI, no significant association was observed (adjusted OR=0.66, p=0.522). No correlation was seen between vitamin D and FBS (r=0.28, p=0.095), 1-hour post-75 g OGTT (r=0.26, p=0.643), and 2-hour post-75 g OGTT (r=0.28, p=0.113).

Conclusion

There was an association found between maternal serum vitamin D level and GDM in the univariate analysis, but none was evident after adjusting for possible confounders. The unanticipated high prevalence of low vitamin D levels among pregnant Filipinos needs to be verified in future studies.

Evaluation of Maternal Serum 25-Hydroxyvitamin D Levels in Patients with Hyperemesis Gravidarum at Early Gestational Weeks

Aim: The aim of this study was to compare vitamin D levels between pregnant women with hyperemesis gravidarum before 12 weeks of gestation and healthy pregnant women at similar ages. Methods: Sixty pregnancies with hyperemesis gravidarum and 60 age compatible healthy pregnancies applied to our facility were included in the study. Demographic characteristics, maternal thyroid function tests and 25-Hydroxyvitamin D levels were evaluated. Student t test was used for the variables with normal distribution and Mann-Whitney U test was used to analyze the variables without normal distribution. Results: Only one pregnant woman had normal vitamin D levels (>30ng/ml), whereas 71 patients had deficiency (10-30 ng/ml), and 48 had severe deficiency (<10 ng/ml). The mean vitamin D level of the total 120 pregnancies was 11.9±5.00 ng/ml (9.92±3.67 ng/ml in case group, 13.88±5.38 ng/ml in control group). The mean value of vitamin D was found to be significantly lower in hyperemesis gravidarum. 45% (n=27) of the pregnant women had vitamin D deficiency, whereas 55% (n=33) of them had severe deficiency. Free T3 and T4 levels were significantly higher than the control group, and thyroid-stimulating hormone level was significantly lower. Conclusion: Vitamin D levels of pregnant women with hyperemesis gravidarum were significantly lower. Vitamin D deficiency should be considered in patients with hyperemesis gravidarum. Keywords: pregnancy, hyperemesis gravidarum, Vitamin D deficiency

The Effect of Vitamin D Supplementation on Improving Glycaemic Control in Diabetic Vitamin D-Deficient Pregnant Women: A Single-Blinded Randomized Control Trial

INTRODUCTION

Gestational diabetes mellitus is one of the most common conditions complicating pregnancy. Vitamin D deficiency is closely associated with gestational diabetes mellitus.

OBJECTIVES

To study the effect of vitamin D supplementation on diabetic pregnant women with vitamin D deficiency.

METHODS

This randomized controlled study was conducted with 100 diabetic pregnant women. They were randomized into group A and group B. Group A were screened for vitamin D deficiency once diagnosed with GDM of which 40 were found to be deficient and allotted to group D (n = 40) and were supplemented with 60,000 units of vitamin D3 per month. Group B were given routine antenatal care and were screened for vitamin D deficiency when they were admitted for delivery, and 39 of them were found to have vitamin D deficiency and were studied as control group C (n = 39). Ten women in both the groups had normal levels of vitamin D, and one of them was excluded from the study as she had molar pregnancy. The vitamin D supplemented group D and the control group C were matched for age and parity at the baseline.

RESULTS

There was a significant increase in the mean insulin and metformin requirements in both the supplemented and control groups. Vitamin D supplementation did not improve the glycaemic control in diabetic pregnant women.

CONCLUSION

Vitamin D supplementation did not decrease insulin resistance or improve the glycaemic control in diabetic pregnant women with vitamin D deficiency.

Serum vitamin D deficiency and risk of gestational diabetes mellitus: a meta-analysis

INTRODUCTION

This meta-analysis was performed to confirm the relationship of gestational diabetes mellitus (GDM) and vitamin D.

MATERIAL AND METHODS

PubMed and CNKI databases were searched for relevant articles. Standard mean difference (SMD) along with 95% CI was used to compare vitamin D level between women with GDM and healthy subjects. The correlation coefficient between the vitamin D and homeostasis model assessment-insulin resistance index (HOMA-IR) was analyzed.

RESULTS

The vitamin D level of GDM subjects was much lower than healthy subjects (SMD = -0.71, 95% CI: -0.91, -0.50). Vitamin D deficiency was associated with high risk of GDM (OR = 1.15, 95% CI: 1.07-1.23). Vitamin D was negatively correlated with HOMA-IR (r = -0.62, 95% CI: -0.85, -0.39). The analysis showed no publication bias (Egger's: p = 0.197; Begg's: p = 0.786).

CONCLUSIONS

Vitamin D is closely associated with the onset of GDM.

Significance of Vitamin D on the Susceptibility of Gestational Diabetes Mellitus - A Meta-Analysis

Vitamin D plays an important role in glucose tolerance by stimulating insulin secretion and evidences suggest a contradictory result on the association between vitamin D status and risk of developing gestational diabetes mellitus (GDM). The present updated meta-analysis has been undertaken to find out the joined effect of vitamin D status on the risk of effect GDM considering previously published articles. Data were collected through literature search using electronic databases to retrieve relevant published research articles using various combinations of the following keywords, "vitamin D," "vitamin D deficiency," "cholecalciferol," "25-hydroxyvitamin D," "25(OH) D," "gestational diabetes mellitus," and "GDM." A total of 36 studies including 7,596 GDM cases and 23,377 non-GDM controls were involved in this study. Overall, pooled meta-analysis showed that pregnant women diagnosed with GDM have 18% higher risk of GDM risk when compared with controls [odds ratio (OR) = 1.18, 95% confidence interval (CI) 1.10-1.25; P = 0.00] with high heterogeneity (I² = 73.29). The mean difference was also significantly different between cases and controls (OR = -0.18, 95% CI - 0.22 to - 0.14; P = 0.00). Subgroup analysis showed significant results with age more than 30 years, Asian and European regions, and case-control, cross-sectional, and nested case-control study design. Low concentration of vitamin D is associated with the development of GDM. Although in future more studies especially systematically designed clinical trials based on vitamin D supplementation with large sample size on different population are needed to elucidate the exact concentration of vitamin D during pregnancy as well as before and after pregnancy.

Effects of Vitamin D Deficiency on Incidence Risk of Gestational Diabetes Mellitus: A Systematic Review and Meta-analysis

INTRODUCTION

Proper nutrition is important for overall health, and it reduces healthcare costs associated with malnutrition. Many studies have investigated vitamin D deficiency and its role in gestational diabetes and controversial data have reported. A comprehensive consideration of articles in this field provides the possibility of a general study of this relationship. This meta-analysis is an evaluation of the relationship between vitamin D deficiency and gestational diabetes.

MATERIAL AND METHODS

Different databases (such as PubMed, Science Information Institute, EmBase, Scopus, and the Cochrane Library) were searched for studies and eligible English articles published before February 2017 that have reported the risk of gestational diabetes in relation to vitamin D deficiency. This relationship was measured using odds ratios (ORs) with a confidence interval (CI) of 95%. The influence of each study was measured through sensitivity analysis. Funnel plots, Egger regression tests, and the Begg-Mazumdar correlation test were used to determine bias or publication bias. STATA (version 11.2) was used for all analyses.

RESULTS

Twenty-six studies were selected as eligible for this research and included in the final analysis. In general, vitamin D deficiency among mothers may be related to an increased risk of gestational diabetes (OR = 1.18; 95% CI, 1.01-1.35; p < 0.001). The serum level of 25(OH)D is less meaningful in people with gestational diabetes than in those who have normal glucose tolerance. Subgroup analysis showed that the results concerning this association may vary with study design but do not change with country of origin.

CONCLUSION

Some evidence has shown that vitamin D deficiency may increase the risk of gestational diabetes.

Hypovitaminosis D in pregnancy in the Mediterranean region: a systematic review

Despite high levels of sunshine, maternal hypovitaminosis D during pregnancy is prevalent in the Mediterranean region. The aim of this study is to systematically review trials that investigated vitamin D concentrations during pregnancy in this region, in order to determine predictors of hypovitaminosis D and explain this phenomenon. After applying inclusion/exclusion criteria, 15 studies were entered into the systematic review involving 2649 pregnant women and 820 neonates. The main outcome was maternal vitamin D status, assessed by serum 25-hydroxy-vitamin D (25(OH)D) concentrations. Possible predictors of the outcome included maternal age, body mass index (BMI), race, socioeconomic status, skin type, gestational age, sun exposure, calcium and vitamin D intake and supplementation, smoking status, parity and season of delivery. Studies differed widely in vitamin D deficiency criteria, method of measurement and outcomes. The prevalence of vitamin D insufficiency ranges from 9.3 to 41.4%, whereas that of vitamin D deficiency from 22.7 to 90.3%. A positive association with 25(OH)D concentrations exists for light skin color, white race, uncovered dressing pattern, maternal vitamin D supplementation and season of gestation (spring/summer). An inverse association exists for BMI and gestational age, whereas data for smoking and socioeconomic status are controversial. We concluded that vitamin D deficiency in pregnancy seems to be quite common, even in the Mediterranean region. Racial, social and cultural habits, as well as the absence of preventive supplementation/dietary strategies, seem to negate the benefits of sun exposure.

Vitamin D Deficiency Increases the Risk of Gestational Diabetes Mellitus: A Meta-Analysis of Observational Studies

The results investigating the relationship between vitamin D levels and gestational diabetes mellitus (GDM) are inconsistent. Thus, we focused on evaluating the association of vitamin D deficiency with GDM by conducting a meta-analysis of observed studies. A systematic literature search was conducted via PubMed, MEDLINE, and Cochrane library to identify eligible studies before August 2015. The meta-analysis of 20 studies including 9209 participants showed that women with vitamin D deficiency experienced a significantly increased risk for developing GDM (odds ratio (OR) = 1.53; 95% confidence intervals (CI), 1.33, 1.75) with a little heterogeneity (I² = 16.20%, p = 0.252). A noteworthy decrease of 4.93 nmol/L (95% CI, −6.73, −3.14) in serum 25(OH)D was demonstrated in the participants with GDM, and moderate heterogeneity was observed (I² = 61.40%, p = 0.001). Subgroup analysis with study design showed that there were obvious heterogeneities in nested case–control studies (I² > 52.5%, p < 0.07). Sensitivity analysis showed that exclusion of any single study did not materially alter the overall combined effect. In summary, the evidence from this meta-analysis indicates a consistent association between vitamin D deficiency and an increased risk of GDM. However, well-designed randomized controlled trials are needed to elicit the clear effect of vitamin D supplementation on prevention of GDM.

Maternal-fetal impact of vitamin D deficiency: a critical review

Research into the extra-skeletal functions of vitamin D has been expanding in recent years. During pregnancy, maternal vitamin D status may be of concern because of the key role of this vitamin in fetal skeletal development and due to the association between hypovitaminosis D and adverse maternal-fetal outcomes. Therefore, the objective of this manuscript was to review the maternal-fetal impact of gestational vitamin D deficiency and the benefits of vitamin D supplementation during pregnancy. A literature search was performed in PubMed and Embase employing the following keywords: vitamin D deficiency, pregnancy, 25-hydroxyvitamin D, and hypovitaminosis D. All relevant articles in English language published since 1980 were analysed by the two authors. Neonatal complications derived from vitamin D deficiency include low birth weight, growth restriction, and respiratory tract infection. In the mother, vitamin D deficiency has been associated with altered glucose homeostasis and increased incidence of gestational diabetes mellitus, pre-eclampsia, and bacterial vaginosis. However, the current state of the evidence is controversial for some other endpoints and the actual benefit of vitamin D supplementation in pregnancy remains unclear. Additional longitudinal studies may clarify the actual impact of vitamin D deficiency during pregnancy, and randomised trials are required to define the benefits of vitamin D supplementation in reducing the incidence of adverse outcomes in the mother and infant.

ENDOCRINOLOGY IN PREGNANCY: Influence of maternal vitamin D status on obstetric outcomes and the fetal skeleton

Vitamin D status has been increasingly associated with wide-ranging clinical outcomes. There is now a wealth of observational studies reporting on its associations with obstetric complications, including pre-eclampsia, gestational diabetes and the mode and timing of delivery. The findings are inconsistent, and currently there is a lack of data from high-quality intervention studies to confirm a causal role for vitamin D in these outcomes. This is similarly true with regards to fetal development, including measures of fetal size and skeletal mineralisation. Overall, there is an indication of possible benefits of vitamin D supplementation during pregnancy for offspring birthweight, calcium concentrations and bone mass as well as for reduced maternal pre-eclampsia. However, for none of these outcomes is the current evidence base conclusive, and the available data justify the instatement of high-quality randomised placebo controlled trials in a range of populations and health care settings to establish the potential efficacy and safety of vitamin D supplementation to improve particular outcomes.

The impact of Vitamin D Replacement on Glucose Metabolism

OBJECTIVE

We investigated the impact of vitamin D supplementation on glucose metabolism in Vitamin D-deficient patients with prediabetes.

METHODS

A total of 66 subjects with the mean ages 52.2±9.9 years were included in this prospective and a 6-month follow-up study between 2008-2010. Vitamin D deficient patients (<25ng/ml) were supplemented with oral Vitamin D.

RESULTS

Vitamin D deficiency (<25ng/ml) was found in 93.9% of the patients. Post replacement Vitamin D levels increased significantly and insulin, HbA1c, and HOMA-IR decreased significantly following Vitamin D replacement. Conclusion : We found Vitamin D deficiency was very common in our study population. In Vitamin D deficient patients, supplementation treatment improved insulin resistance and glycemic parameters. Vitamin D replacement may be a promising intervention for the primary prevention of insulin resistance syndromes.