Researchers Link Behavioral Problems in Children to Irregular Bedtimes

Children who go to sleep at inconsistent times of day are more likely to have behavioral problems, according to new research published in the journal Pediatrics.

Based on data collected from more than 10,000 children in the UK Millennium Cohort Study, researchers from University College London found that irregular bedtimes in three, five and seven-year-old children can disrupt the body's natural rhythm, which can cause sleep deprivation detrimental to brain maturation and certain behavioral regulations.

Among the three-year-old children included in the study, one in five had an inconsistent bedtime. The researchers also found that children who's bedtime was irregular or who went to bed after 9:00 at night most often came from socially disadvantaged backgrounds, a fact the researchers took into account during the study.

"Not having fixed bedtimes, accompanied by a constant sense of flux, induces a state of body and mind akin to jet lag and this matters for healthy development and daily functioning," said Yvonne Kelly, a professor of epidemiology and public health at UCL.

"We know that early child development has profound influences on health and well-being across the life course. It follows that disruptions to sleep, especially if they occur at key times in development, could have important lifelong impacts on health."

Kelly and her colleagues found a "clear and statistically significant" link between irregular bedtimes and behavioral problems. Children growing up without regular bedtimes were observed with increased hyperactivity, conduct problems with peers at school and emotional difficulties. Children in the study who had irregular bedtimes but later switched to a consistent bedtime had clear improvements in their behavior, the researchers found.

"What we've shown is that these effects build up incrementally over childhood, so that children who always had irregular bedtimes were worse off than those children who did have a regular bedtime at one or two of the ages when they were surveyed," Kelly said. "But our findings suggest the effects are reversible. For example, children who change from not having to having regular bedtimes show improvements in their behavior."