Irregular bedtimes linked to behaviour problems in children, study finds

Children with irregular bedtimes are more likely to have behaviour problems, according to new research using data from the Millennium Cohort Study.

Researchers at University College London compared the bedtimes of more than 10,000 children at ages three, five and seven to behaviour reports from their mothers and teachers.

They found that children who went to bed at different times every night were more likely to have behaviour issues, including hyperactivity, conduct problems and emotional difficulties, than those with regular bedtimes.

Children’s behaviour worsened as they got older if they continued to have irregular bedtimes. However, those who changed to having a more regular bedtime showed a clear improvement in their behaviour.

Irregular bedtimes were most common at age three, when around one in five children went to bed at varying times. In contrast, by age seven, more than half of the children went to bed regularly between 7:30 and 8:30pm.

The researchers also found that children who had irregular bedtimes or went to bed after 9pm were more likely to come from more socially disadvantaged backgrounds.

Professor Yvonne Kelly, who led the research, noted that irregular bedtimes could disrupt natural body rhythms and cause sleep deprivation, affecting brain development and the ability to control certain behaviours.

She said:“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.”

“As it appears the effects of inconsistent bedtimes are reversible, one way to try and prevent this would be for health care providers to check for sleep disruptions as part of routine health care visits. Given the importance of early childhood development on subsequent health, there may be knock-on effects across the life course. Therefore, there are clear opportunities for interventions aimed at supporting family routines that could have important lifelong impacts.”

The same research team recently reported that boys and girls who had irregular bedtimes at age 3 had lower scores in reading, maths and spatial awareness at age 7.

‘Changes in bedtime schedules and behavioral difficulties in 7 year old children’, by Yvonne Kelly, John Kelly and Amanda Sacker, was published in the Pediatrics journal on 14 October 2013.