Vitamin D Deficiency With High Parathyroid Hormone Levels Is Related to Late Onset Sepsis Among Preterm Infants

Summary: Preterm infants (PT) are at greater risk for vitamin D deficiency, which relates to the possibility of a higher incidence of comorbidities. Our goal was twofold, 1) to monitor vitamin D, calcium, phosphorus, parathyroid hormone (PTH), matrix metalloproteinase-8 (MMP-8) serum levels at three-time points during hospitalization, and 2) to assess the association between 25-hydroxyvitamin D (25OHD) levels and outcome in preterm Methods: We carried out a follow-up on 50 Caucasian preterm infants ≤ 32 weeks of gestational age (GA) and/or ≤ 1500 g birth weigh PTs at 28 days and at 4 months. They were divided into two subgroups for tests of association with clinical outcomes based on vitamin D deficient infants (25(OH) D cord blood levels: ≤ 20 ng/ml). At an initial stage, 25-OHD levels were determined in maternal/preterm blood samples and were compared with full term delivery infants. Results: : There were no differences in 25(OH) D serum levels at birth when comparing PTs to term infants, or regarding maternal levels. A strongly positive correlation was detected between maternal and neonatal 25(OH) D serum levels in term and preterm infants (r: 0.466; p < 0.001). Newborn with vitamin D deficiency did not have higher incidence in comorbidities. However, if we separate preterm babies in two groups based on vitamin D and PTH (group 1: vitamin D60 pg/mL and group 2: vitamin D>20 plus PTH<60 pg/mL), the PT in group 1 presented higher incidence of LOS (RR: 2 CI95%: 1.31-3.55). No relationship was observed between MMP-8 serum levels and the incidence of sepsis. Conclusions: : This study did not find any evidence of an increase in preterm birth risk related to vitamin D level at birth. Vitamin D deficiency by itself it is not associated to higher incidence in comorbidities. However, the binomial vitamin D-PTH must be taken into consideration .