Sleep and Movement Behaviours in Preschool Children: A Cross-Sectional Study With Compositional Data Analysis

Area of Science:

• Pediatric Sleep Science
• Childhood Physical Activity Research
• Behavioral Chronobiology

Background:

• Reciprocal associations between physical activity and sleep in early childhood remain unclear compared to older age groups.
• Existing research often overlooks the holistic 24-hour behavior cycle, focusing on isolated sleep or activity metrics.
• Compositional data analysis (CoDA) is needed to examine the interplay of sleep and physical activity within a full day.

Purpose of the Study:

• To investigate associations between sleep composition (overnight, 24-hour, nap stages) and physical activity in preschool children.
• To determine if 24-hour sleep-wake behaviors differ based on sex or nap habituality.
• To apply CoDA for a comprehensive understanding of young children's daily behavior patterns.

Main Methods:

• Actigraphy data from 272 preschool children (aged 4.2 ± 0.8 years) were used to estimate sleep and physical activity.
• Nap sleep stages were analyzed using polysomnography in a subset of 31 children.
• Multivariate regression models analyzed compositional 24-hour time use differences related to sex and nap habits.

Main Results:

• Nap sleep stage composition was not significantly associated with physical activity levels.
• 24-hour time-use compositions, including both sleep and wake components, varied significantly by age, sex, and nap habituality.
• Total sleep time did not differ across these groups, but the distribution of sleep and wake components did.

Conclusions:

• Nap habits, age, and sex are significant factors influencing the composition of sleep and physical activity within a 24-hour cycle in preschoolers.
• CoDA is a valuable approach for analyzing complex 24-hour behavior patterns in children.
• Further research should examine these associations in diverse populations and incorporate detailed sleep assessments.