Data_Sheet_1_Is the association between sleep and socio-emotional development mediated by weight in toddlers aged 12 to 36 months?.docx

Introduction

Childhood is an important stage for socio-emotional development. Understanding the associations of lifestyle habits with the healthy development of social and emotional skills is crucial for better interventions early in life. This study aims to analyze the association between sleep and socio-emotional development in toddlers aged 12 to 36 months and examine whether weight mediated these associations.

Methods

This study is part of a cluster randomized controlled trial developed in Portuguese childcare centers. A sample of 344 children (176 females) enrolled in the study. Participants’ anthropometrics were measured while at childcare centers using standardized procedures. Body mass index (BMI) was computed as the body weight/height2 (kg/m2) ratio. Sleep quality was collected with the Tayside Children’s Sleep Questionnaire, a 10-item scale that evaluates the child’s ability to initiate and maintain sleep. Two additional questions regarding sleep duration were added. Parental questionnaires assessed the child’s sex and date of birth, socioeconomic status, and total energy intake (TEI). Motor (fine and gross) was assessed using Bayley-III scales and socio-emotional (SE) by the Greenspan Social–Emotional Growth Chart questionnaire. Linear regression models were used to examine the associations between sleep (duration and quality) and SE with adjustments for sex, age, BMI, mothers’ education, motor development, and TEI. Mediation analysis was conducted using path analysis.

Results

SE development was significantly associated with nighttime sleep duration even when adjusted for confounders (β = 0.223; 95% CI: 0.001, 0.004 and β = 0.168; 0.0003, 0.003; respectively). Sleep quality was not significantly associated with SE development, and the weight did not explain the associations between sleep and SE development.

Conclusion

This study supports that sleep duration is directly associated with SE development in toddlers. From a public health perspective, sleep duration should be prioritized in intervention programs to improve socio-emotional development early in life.