Healthcare

Recent suggestion due to less time of night sleep in earlier life said that it could associated with obesity in later life.

The investigator evaluated the link of sleep duration between daytime vs nighttime and subsequent obesity in 1930 children and adolescents (age range 0 – 13 years old) at baseline in 1997 by using the US Panel Survey of Income Dynamic Child Development Supplement (PSID-CDS) in 1997 and 2002.

According to the authors of the study, Janice F. Bell PhD, MPD, from the University of Washington in Seattle, California, Los Angeles, short duration of sleep in children and adolescents may increase the risk of obesity. Evidence is accumulating from cross-sectional population studies to support a robust contemporaneous relationship between shortened sleep duration and unhealthy weight status in children and adolescents. In several studies, a strong dose-response relationship is evident with increasing odds of overweight/obesity associated with fewer hours spent sleeping.

In this study, short sleep duration in daytime and nighttime at baseline were defined as less than the 25th percentile of age-normalized sleep scores.
At follow-up in 2002, body mass index (BMI) was converted to age-specific z scores and characterized as normal weight, overweight, or obese with use of established cutoff points.
The relationship between BMI classification and short daytime and nighttime sleep at baseline and follow-up was assessed with ordered logistic regression. The investigators also use important covariates including the status of socioeconomic, BMI of the parents, and BMI at baseline for children older than 4 years.

They found that among children aged 0 to 4 years at baseline, nighttime sleep with short duration at baseline was significantly linked to higher risk for subsequent overweight or obesity.
However, among children aged 5 to 13 years at baseline, the sleep was not linked to subsequent weight status, but contemporaneous sleep was inversely associated.
In both group, daytime sleep was not significantly associated with subsequent obesity.

Published as September issue of the Archives of Pediatric & Adolescent Medicine, the authors write, “In the older cohort, nighttime sleep at follow-up was associated with marginally increased odds of obesity at follow-up, while sleep duration 5 years prior had no significant effect.”
According to the authors, their findings suggest that there is a critical window prior to age 5 years when nighttime sleep may be important for subsequent obesity status.

Despite several limitations in this study such as collection of sleep data for only 2 days in a year, lack of baseline BMI data for the younger children, potential confounding by physical activity and diet, and reliance on parental report for baseline weight, the study authors conclude, “Shortened sleep duration in early life is a modifiable risk factor with important implications for obesity prevention and treatment.”

They added, “Insufficient nighttime sleep among infants and preschool-aged children may be a lasting risk factor for subsequent obesity. Napping does not appear to be a substitute for nighttime sleep in terms of obesity prevention.”