Excessive Daytime Sleep during Infancy may predict poor working memory at school age

A recent study aims to analyze the association between DSD during infancy and cognitive development at 6 and 10 years of age. This study was published in the Journal Of Clinical Sleep Medicine by Jianfei Lin and colleagues. Daytime sleep duration in infancy is considered an indicator of sleep maturation and is closely linked to cognitive development. However, the long-term implications of excessive daytime sleep during infancy on cognitive function in school-aged children remain unclear.

The study included 262 mothers and their newborns from the Shanghai Sleep Birth Cohort Study, with follow-ups spanning from 42 days to 10 years. Sleep parameters were assessed using parent-report questionnaires at each follow-up, while cognitive development was evaluated using the Wechsler Intelligence Scale for Children, 4th edition at 6 and 10 years.

The key findings of the study were:

• Two distinct trajectories of DSD during early childhood were identified: "typical DSD" (66.7%) and "infancy excessive DSD" (33.3%).

• Children in the "infancy excessive DSD" trajectory exhibited significantly lower working memory scores compared to those in the "typical DSD" trajectory at 6 years (Mean difference=5.90, 95% CI [1.83, 9.96], p=0.005) and 10 years (Mean difference=4.37, 95% CI [0.26, 8.48], p=0.037).

• Additional analysis in a relatively homogeneous sample consistently showed correlations between DSD trajectories and working memory performance.

• No consistent significant differences were found in other domains of cognitive development.

Excessive daytime sleep during infancy may serve as an early indicator for poor working memory in school-aged children. These findings underscore the importance of monitoring sleep patterns during infancy and their potential impact on long-term cognitive development. Further research is needed to elucidate the underlying mechanisms and explore interventions to support cognitive health in children with excessive DSD during infancy.

Reference:

Lin, J., Jiang, Y., Xiao, X., Zhu, Q., Wang, G., Lin, Q., & Jiang, F. Daytime sleep duration during infancy as an indicator for cognitive development at school age: a prospective cohort study. Journal of Clinical Sleep Medicine: JCSM: Official Publication of the American Academy of Sleep Medicine,2024. https://doi.org/10.5664/jcsm.11062