Age-related changes in sleep macroarchitecture across childhood and adolescence in a paediatric clinical polysomnography cohort

Objective To characterise age-related changes in sleep macroarchitecture, consolidation and fragmentation across childhood and adolescence in a large real-world paediatric clinical polysomnography cohort, and to examine their relationship with respiratory disturbance severity. Methods We performed a retrospective observational analysis of 419 polysomnographies from children aged 1–18 years at a tertiary sleep unit between January 2023 and December 2024. Participants were categorised as toddlers, pre-schoolers, school-aged children and adolescents. Sleep macroarchitecture, consolidation and fragmentation parameters were scored according to paediatric American Academy of Sleep Medicine criteria. Multivariate general linear models assessed age-group differences, with additional adjustment for apnoea–hypopnoea index and Bonferroni post-hoc testing. Results Total sleep time decreased with age, while sleep onset and rapid eye movement sleep latencies increased during adolescence. Sleep architecture showed a developmental shift, mainly characterised by increasing Stage N2 and decreasing rapid eye movement sleep proportions, with less robust changes in Stage N3. Fragmentation indices, including arousal index, were higher in adolescents. After adjustment for apnoea–hypopnoea index, age group remained an independent predictor of macroarchitecture, consolidation and fragmentation, whereas respiratory severity was mainly associated with micro-fragmentation indices. Conclusions Sleep macroarchitecture continues to mature throughout childhood and adolescence, with adolescents frequently exhibiting adult-like sleep patterns largely independent of respiratory disturbance severity. Significance Age-related changes in sleep macroarchitecture and fragmentation provide physiological context for interpreting paediatric polysomnography, particularly near the transition between paediatric and adult scoring frameworks.