Interaction effect of gestational age on the association between sleep and neurodevelopmental outcomes in early childhood: A longitudinal study from birth to 24 months

Objective

To investigate how gestational age at birth (GA) affects the sleep durations from birth to 24 months old and its association with neurocognitive outcomes.

Study design

Longitudinal sleep data from birth to 24 months of age were collected using the Brief Infant Sleep Questionnaire (BISQ). Of the 481 participants, 259 underwent neurodevelopment assessments at 24 months using the Bayley Scales of Infant and Toddler Development, Third Edition.

Results

Daytime sleep (DS) in the first 3 months(3 m) significantly differed between term-born infants and moderate to late preterm (MLPT) infants (6.32 vs 6.86 h; p < 0.05). Shorter DS and longer nighttime sleep (NS) after 3 months of age were significantly associated with better language outcome. Significant interaction between GA and 24-month NS indicates that this effect was stronger in infants born at a more mature GA. Longer DS from birth to 24 months was associated with a 29 % to 48 % higher risk of language delay. GA also influenced the effect of 6-month total sleep (TS) on predicting the risk of cognitive, language, and motor delay, suggesting a higher risk of delay for more premature infants who sleep longer at 6 months.

Conclusion

This study revealed the complex associations between longitudinal infant sleep and neurodevelopmental outcomes, with GA serving as a moderating factor. The study highlights a need to further explore the associations between GA, early life sleep durations, and neurodevelopmental outcomes.