Sleep-wake transitions in premature neonates predict early development

OBJECTIVE: To identify patterns of sleep-wake transitions in the neonatal period that might differentiate premature infants who would show better or worse outcomes in multiple developmental domains across the first 5 years of life. METHODS: Participants were 143 low birth weight premature infants (mean birth weight: 1482 g; mean gestational age [GA]: 31.82 weeks). Sleep states were observed at a GA of 37 weeks in 10-second epochs over 4 consecutive evening hours and were analyzed through mathematical clustering. Neurobehavioral maturation was evaluated with the Neonatal Behavior Assessment Scale at discharge, emotional regulation was assessed during infant-mother and infant-father interactions at 3 and 6 months, cognitive development was measured at 6, 12, and 24 months, and verbal IQ, executive functions, and symbolic competence were tested at 5 years. RESULTS: Three types of state-transition patterns were identified, and no differences in birth weight, GA, or medical risk between the 3 groups were found. Infants whose sleep-state transitions were mainly characterized by shifts between quiet sleep and wakefulness exhibited the best development, including greater neonatal neuromaturation, less negative emotionality, better cognitive development, and better verbal, symbolic, and executive competences at 5 years. In comparison, infants who cycled mainly between states of high arousal, such as active sleep and cry, or between short episodes of active and quiet sleep showed poorer outcomes. CONCLUSIONS: Defining sleep organization on the basis of transitions between states proved useful for identifying risk and resilience indicators in neonatal behavior to predict trajectories of neurobehavioral, emotional, and cognitive growth.