The vitamin D level in umbilical cord blood in premature infants with or without intra-ventricular hemorrhage: A cross-sectional study

Vitamin D and gut microbiome in preterm infants

BACKGROUND

The incidence of vitamin D deficiency among pregnant women remains high and is associated with vitamin D deficiency in infants. In normally breastfed infants, Bifidobacteriaceae and Lactobacillaceae are known to help in maintaining immunotolerance and prevent infection. Vitamin D in the gastrointestinal tract plays a role in determining the composition and function of intestinal bacteria. Preterm infants are vulnerable to intestinal dysbiosis and sepsis due to bacterial translocation. This study aimed to determine the association between vitamin D levels and intestinal dysbiosis.

METHODS

It was a cohort study conducted in the Neonatal Unit, Cipto Mangunkusumo Hospital, Tertiary hospital in Indonesia, from November 2019 to January 2021. The inclusion criteria in this study were preterm infants with a gestational age of less than 32 weeks or a birth weight of less than 1500 g. Total 25-hydroxyvitamin D (25(OH)D) levels were collected from the umbilical cords of very preterm or very low birth weight infants. A fecal examination was performed on the seventh day of life to assess intestinal bacteria using real-time PCR for four bacterial genera: Bifidobacteriaceae, Lactobacillaceae, Enterobacteriaceae, and Clostridiaceae.

RESULTS

A total of 43 infants were included in this study. Among the subjects, 53.4% had vitamin D deficiency. There was no association identified between vitamin D deficiency and intestinal dysbiosis (RR 0.67; 95% CI (0.15-2.82), p-value = 0.531). However, the ratio of Lactobacillacecae to Enterobacteriaceae was lower in those with vitamin D deficiency.

CONCLUSION

Vitamin D deficiency was not associated with dysbiosis in preterm infants. However, this study found that the ratio of Lactobacillaceae to Enterobacteriaceae in those with vitamin D deficiency was lower than in those without vitamin D deficiency. Further research is warranted to confirm this finding.

High prevalence of hypovitaminosis D3 among pregnant women in central Iran: correlation with newborn vitamin D3 levels and negative association with gestational age

OBJECTIVE

Hypovitaminosis D3 is a significant concern among pregnant women and their newborns because vitamin D3 (Vit-D3) plays a crucial role in embryonic growth, development, and health. This study aimed to evaluate the Vit-D3 status of a group of pregnant Iranian women and its association with newborn Vit-D3 levels, medical and clinical indices after delivery.

METHODS

A total of 206 pregnant women and their newborns were assessed for Vit-D3 levels and their correlation with gestational age. Mean±standard deviation (SD) or the orders (non-parametric tests) of variables were compared, and correlation estimations were performed to elucidate any differences or associations between groups, with a confidence interval of at least 0.95.

RESULTS

The mean±SD of mothers' age and gestational age were 29.65±6.18 years and 35.59±1.6 weeks, respectively. Neonatal Vit-D3 levels were associated with maternal age. Using a 30 ng/mL cutoff point for serum Vit-D3 levels, 83.5% of pregnant women and 84.7% of newborns had hypovitaminosis D3. The average Vit-D3 levels of mothers and newborns at delivery time were 23.5±8.07 ng/mL and 20.76±9.14 ng/mL, respectively. Newborn Vit-D3 levels were positively correlated with maternal Vit-D3 serum levels (R=0.744; P<0.001) and gestational age (R=0.161; P=0.022). In newborns, head circumference was inversely correlated with bilirubin level (R=-0.302; P<0.001) but directly associated with weight (R=0.640; P<0.001).

CONCLUSION

Hypovitaminosis D3 remains a significant challenge for pregnant Iranian women. Maternal Vit-D3 levels provide for the newborn's needs, particularly in the late stages of pregnancy. Therefore, Vit-D3 supplementation and regular monitoring are essential for pregnant women and their newborns.

Evaluation of Maternal and Infantile Levels of Vitamin D in Preterm Infants

INTRODUCTION

Vitamin D deficiency is highly prevalent during pregnancy and in premature infants. This study was done to investigate the maternal and infantile levels of vitamin D in preterm infants.

METHODS

Using available sampling during 2018-2020, the maternal and umbilical cord serum levels of vitamin D were measured in 294 premature infants in Ghaem Hospital, Mashhad, Iran. A researcher- made questionnaire consisting of neonatal demographic and clinical characteristics was used as the data collection tool. Both maternal and placental vitamin D levels were categorized into four classes: severe deficiency (vitamin D<10 ng/ml), moderate deficiency (10.1≤vitamin D≤20 ng/ml), mild deficiency (20.1≤vitamin D≤30 ng/ml) and normal (vitamin D >30.1ng ml).

RESULTS

Vitamin D deficiency was seen in 89% of premature infants (46.6% severe, 30.6% moderate, and 11.9% mild). Serum levels of vitamin D were 18.28±13.94 ng/ml and 14.10±9.70 ng/ml in mothers and infants, respectively. The infants below and above 32 weeks exhibited vitamin D values of 10.97±6.31 ng/ml and 18.05±11.64 ng/ml, respectively. The difference in vitamin D levels between boys (12.59±8.40 ng/ml) and girls (16.05±11.45 ng/ml) was found to be significant (P=0.009). Moderate and severe vitamin D deficiency was more common at earlier pregnancy ages (P=0.001).

CONCLUSION

Vitamin D deficiency is more common and severe in preterm infants and their mothers. Controlling vitamin D levels during pregnancy, especially in women at risk of preterm labor and preterm infants, may help reduce prematurity problems.

What is the Current Role for Vitamin D and the Risk of Stroke?

INTRODUCTION

Increasing evidence supports the relationship between vitamin D and stroke. Vitamin D has now been proposed as a prognostic biomarker also for functional outcome in stroke patients.

METHODS

A revision of the data suggests that low vitamin D is associated more with ischemic than with haemorrhagic stroke, even if the role of optimal vitamin D levels for vascular wall is still unclear. Vitamin D deficiency induces with different mechanisms an alteration of vascular wall.

RESULTS

However, to date, the research supporting the effectiveness of vitamin D supplementation in stroke and in post-stroke recovery is still inadequate and conclusive evidences have not been published.

CONCLUSION

In this review, we provide a better understanding of the role of vitamin D in stroke.