Mediation Effect of Social Distancing on Neonatal Vitamin D Status and Related Clinical Outcomes during the Coronavirus Disease-19 Pandemic.

Background: We analyzed the impact of social distancing (SD) on vitamin D status and associated morbidity in neonates during the coronavirus disease (COVID-19) pandemic. Methods: Serum levels of 25-hydroxy vitamin D (25OHD) and clinical characteristics of newborn infants before (2019) and during SD (2021) were compared. Results: A total of 526 neonates (263 in 2019 and 263 in 2021) were included. The rate of vitamin D deficiency in neonates (47.1% vs. 35.4 %, p = 0.008) decreased and the rate of maternal vitamin D intake increased (6.8% vs. 37.6%, p < 0.001), respectively, during SD compared to those in 2019. The rates of hypocalcemia (12.5% vs. 3.8%, p < 0.001) and respiratory illness (57.0% vs. 43.0%, p = 0.002) decreased during SD. Neonatal vitamin D deficiency during SD was associated with maternal vitamin D supplementation (odds ratio [OR] = 0.463, p = 0.003) but was not associated with SD (OR = 0.772, p = 0.189). The mediation effect of SD on neonatal morbidity by neonatal vitamin D status was statistically insignificant. Conclusions: SD might affect the increased maternal vitamin D intake and decreased neonatal vitamin D deficiency. However, neonatal morbidity was not affected by SD, even with neonatal vitamin D status changes. [ABSTRACT FROM AUTHOR]