HealthDay News — More frequent exposure to late sleep is associated with increases in adiposity in children aged 2 to 6 years, especially among those with overweight and/or obese parents, according to a study published online Feb. 18 in Pediatrics.
Lijuan Xiu, M.D., from the Karolinska Institutet in Stockholm, and colleagues compared sleep in young children at different obesity risks, including 43 with normal-weight parents (low obesity risk) and 64 with overweight and/or obese parents (high obesity risk). Actigraphy was used to measure sleep yearly from ages 2 to 6 years. Five sleep characteristics were examined, with a higher score indicating more frequent exposure.
The researchers found that children at different risks had no difference in sleep patterns. Across ages, there was an association for higher short sleep duration score with a greater increase in body mass index (BMI) z score (0.12; 95 percent confidence interval [CI], 0.01 to 0.25). A higher late sleep score was associated with greater increases in BMI z score and waist circumference (0.16 [95 percent CI, 0.05 to 0.27] and 0.60 cm [95 percent CI, 0.23 to 0.98], respectively), independent of sleep duration. Children at high risk and with habitual late sleep had greater increases in the BMI z score and waist circumference compared with those at low risk and without habitual late sleep (0.93 [95 percent CI, 0.40 to 1.45] and 3.45 cm [95 percent CI, 1.78 to 5.12], respectively).
These data “make an important contribution to the accumulating evidence supporting a link between decreased sleep and adiposity,” write the authors of an accompanying editorial. “Whether this association is causal, and therefore amenable to intervention, will be a far more difficult question to answer.”