Cord-blood vitamin D level and night sleep duration in preschoolers in the EDEN mother-child birth cohort

TL;DR

This study investigates the association between cord-blood vitamin D levels at birth and sleep duration trajectories in preschool children, finding that lower vitamin D levels may increase the likelihood of persistent short sleep duration.

Contribution

It provides the first longitudinal evidence linking cord-blood vitamin D deficiency to sleep duration patterns in a general pediatric population.

Findings

Lower vitamin D levels are associated with higher odds of short sleep trajectories.

No significant association was found between vitamin D and other sleep patterns.

Results suggest vitamin D status at birth may influence sleep duration in early childhood.

Abstract

Objective: 25-hydroxyvitamin D (25OHD) deficiency has been associated with sleep disorders in adults. Only three cross-sectional studies were performed in children and showed an association between 25OHD deficiency and both obstructive sleep apnea syndrome and primary snoring. No longitudinal study has been performed in children from the general population. We analyzed the association between cord-blood vitamin D level at birth and night-sleep duration trajectories for children between 2 and 5-6 years old in a non-clinical cohort.Method: We included 264 children from the French EDEN mother-child birth-cohort with both cord-blood 25OHD level determined by radio-immunoassay at birth, and night-sleep trajectories for children between 2 and 5-6 years old obtained by the group-based trajectory modeling method. Associations between 25OHD and sleep trajectories were assessed by multinomial logistic regression adjusted for maternal and child characteristics.Results: The trajectories short sleep (<10h30/night), medium-low sleep (10h30-11h00/night), medium-high sleep ($\approx$11h30/night), long sleep ($\ge$11h30/night) and changing sleep (decreased from $\ge$11h30 to 10h30-11h00/night) represented 5%, 46%, 37%, 4% and 8% of the children, respectively. The mean 25OHD level was 19 ng/ml (SD=11, range 3 to 63). It was 12 (SD=7), 20 (SD=11), 19 (SD=10), 14 (SD=7) and 16 (SD=8) ng/ml for children with short, medium-low, medium-high, long and changing sleep trajectories, respectively. On adjusted analysis, for each 1-ng/ml decrease in 25OHD level, the odds of belonging to the short sleep versus medium-high sleep trajectory was increased (odds ratio =1.12, 95% confidence interval [1.01-1.25]). We found no other significant association between 25OHD level and other trajectories.Conclusion: Low 25OHD level at birth may be associated with increased probability of being a persistent short sleeper in preschool years. These results need confirmation.