Sleep pattern and body mass index gain in Indigenous Australian children

Abstract

Purpose

This study aims to explore different sleep patterns in Indigenous Australian children and assess the role of sleep patterns in longitudinal changes in body mass index (BMI).

Methods

This work is based on wave 5 to wave 8 (2012–2015) data of the Australian Longitudinal Study of Indigenous Children (LSIC) cohort. Latent class analysis was used to determine distinct sleep patterns, taking into account weekday sleep duration, weekdays and weekends bedtimes, and weekday wake times. Multilevel models with a random intercept for child and geographic clusters were used to investigate the role of baseline sleep pattern in predicting longitudinal changes in BMI.

Results

Baseline data for 1,258 children (50.7% males), mean age 6.32 years (SD ± 1.52), indicated the presence of five classes of sleep patterns: early/long sleepers (4.5%), normative sleepers (25.5%), late sleepers (49.9%), consistent late sleepers (11.1%), and early risers (9%). Family income, child health, food choices, sleep problems, geographic remoteness and area-level disadvantage, were found to be significantly associated with sleep patterns in children. Regression results indicate that late sleep pattern is significantly associated with longitudinal gains in BMI. Compared with early sleepers, consistent late sleepers were found to have a significant increase in BMI (β = 1.03, 95% CI: 0.001–2.05, p = 0.05).

Conclusions

This study underscores the importance of looking beyond sleep duration and highlighting the positive outcomes of early bedtimes in children. As sleep pattern is modifiable, this offers the opportunity for improvement in sleep and protecting against future weight gain in Indigenous children.