Sleep habits and weight status in Brazilian children aged 4–6 years of age: the PREDI study

• Published in: Sleep medicine Vol. 87; pp. 30 - 37
• Main Authors: Schultz, Lidiane Ferreira, Mastroeni, Silmara Salete de Barros Silva, Rafihi-Ferreira, Renatha El, Mastroeni, Marco F.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.11.2021
• Subjects: Bedtime routine; Birth Cohort; Body Mass Index; Brazil - epidemiology; Child; Child, Preschool; Children; Cohort Studies; Female; Habits; Humans; Male; Rhythmicity; Separation affect; Sleep; Sleep habits; Sleep Quality; Brazil; Rhythmicity; Children; Bedtime routine; Sleep habits; Separation affect
• ISSN: 1389-9457; 1878-5506
• DOI: 10.1016/j.sleep.2021.08.020

To evaluate the association of sleep habits with the weight status of children aged 4–6 years. Data were obtained from the PREDI Study, a Brazilian birth cohort study. The current study was carried out in the homes of the participants during two follow-ups: 2016/17 and 2018. The participants were submitted to anthropometric assessment and demographic, socioeconomic and sleep data were obtained. The child's sleep habits were self-reported by the mother or caregiver on the day of the visit and included information on the following sleep habits during the past week: bedtime routine, rhythmicity, and separation affect determined with the Sleep Habits Inventory for Preschool Children and the Sleep Habits Inventory. Logistic regression and gamma-log regression analyses were used to examine the association of sleep habits with excess body weight of children in the two follow-ups according to sex. Of the 217 and 185 children included in 2016/17 and 2018, respectively, 66 (30.6%) and 48 (25.9%) had a BMI >85th percentile at 4–6 years, respectively. The median rhythmicity score was higher in children with excess body weight (p = 0.05). Adjusted analysis showed that rhythmicity was associated with excess body weight of girls at ages 4–5 years (OR = 1.42, 95% CI: 1.09–1.86, p = 0.009) and 6 years (OR = 1.32, 95% CI: 1.06–1.65, p = 0.015), even after adjustment for other important covariates. Additionally, the sleep habit “separation affect” was inversely associated with the child's BMI in boys (β = −0.005, 95% CI: −0.010–0.000, p = 0.037). In the present study, rhythmicity problems were associated with increased odds of girls aged 4–6 years having excess body weight. These results are important from a public health perspective since strategies aimed at preventing excess body weight in children need to consider the child's sleep quality as a potential risk factor, especially rhythmicity. •Children with altered sleep habits are more likely to have excess body weight in the early years of school.•Changes in rhythmicity in children were associated with excess body weight.•The higher the rhythmicity scores, the greater the child's BMI, especially in girls.•The higher the separation affect scores, the lower the child's BMI in boys.