Relationship between serum 25(OH)D levels at birth and respiratory distress syndrome in preterm infants / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To investigate the relationship between serum 25-hydroxyvitamin D [25(OH)D] levels at birth and respiratory distress syndrome (RDS) in preterm infants.</p><p><b>METHODS</b>This retrospective study recruited preterm infants with gestational age of below 34 weeks who were born between January 2014 and December 2016. These preterm infants were divided into two groups: RDS (n=72) and control (n=40). Clinical data of the two groups were collected, including gestational age, birth weight, gender, delivery mode, Apgar scores at 1 minute and 5 minutes, incidence of maternal gestational diabetes mellitus, and use of prenatal steroid hormone. Peripheral blood samples were collected and 25(OH)D levels were measured by chemiluminescence immunoassay. The association between serum 25(OH)D levels at birth and RDS was analyzed by multivariate logistic regression.</p><p><b>RESULTS</b>Apgar scores at 1 minute and 5 minutes and serum 25(OH)D levels in the RDS group were significantly lower than those in the control group (P<0.05), while the rates of neonatal asphyxia and vitamin D deficiency were significantly higher than those in the control group (P<0.05). Multivariate logistic regression analysis showed that neonatal asphyxia (OR=2.633, 95%CI: 1.139-6.085) and vitamin D deficiency (OR=4.064, 95%CI: 1.625-10.165) were risk factors for RDS in preterm infants.</p><p><b>CONCLUSIONS</b>Vitamin D deficiency might be associated with increased risk of RDS in preterm infants. Reasonable vitamin D supplementation during pregnancy might reduce the incidence of RDS in preterm infants.</p>

Vitamin D level at birth and influencing factors in preterm infants / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To investigate vitamin D level at birth and possible influencing factors in preterm infants.</p><p><b>METHODS</b>A total of 600 preterm infants were enrolled, and venous blood samples were collected within 24 hours after birth to measure the serum level of 25-hydroxyvitamin D [25(OH)D]. The effect of sex, birth weight, birth season, gestational age, mother's age, body mass index (BMI) in early pregnancy, delivery mode, and complications during pregnancy on serum 25(OH)D level was analyzed.</p><p><b>RESULTS</b>The rates of vitamin D deficiency, insufficiency, and sufficiency were 42.0%, 38.7%, and 19.3% respectively. The preterm infants born in summer and autumn had a significantly higher serum 25(OH)D level than those born in winter (P<0.05) and a significantly lower incidence rate of vitamin D deficiency than those born in spring and winter (P<0.003). Compared with those whose mothers were aged <30 years, the infants whose mothers were aged ≥30 years had a significantly higher serum 25(OH)D level (P<0.05) and a significantly lower incidence rate of vitamin D deficiency (P<0.017). Compared with those whose mothers were overweight or had normal body weight, the infants whose mothers were obese had a significantly lower serum 25(OH)D level (P<0.05) and a significantly higher incidence rate of vitamin D deficiency (P<0.006). Compared with those whose mothers had no preeclampsia, the infants whose mothers had preeclampsia during pregnancy had a significantly lower serum 25(OH)D level (P<0.05) and a significantly higher incidence rate of vitamin D deficiency (P<0.017). The multivariate analysis showed that birth in winter and spring, mother's age <30 years, and early-pregnancy BMI ≥28 kg/mwere risk factors for vitamin D deficiency (P<0.05).</p><p><b>CONCLUSIONS</b>There is a high prevalence of vitamin D deficiency in preterm infants. Vitamin D supplementation should be given to the preterm infants with high-risk factors for vitamin D deficiency.</p>