By Alan Mozes
MONDAY, Jan. 5, 2015 (HealthDay News) -- A smartphone in a child's bedroom may undermine good sleep habits even more than a TV, new research suggests.
A study of more than 2,000 elementary and middle-school students found that having a smartphone or tablet in the bedroom was associated with less weekday sleep and feeling sleepy in the daytime.
"Studies have shown that traditional screens and screen time, like TV viewing, can interfere with sleep, but much less is known about the impacts of smartphones and other small screens," said study lead author Jennifer Falbe, of the School of Public Health at the University of California, Berkeley.
Small screens are of particular concern because they provide access to a wide range of content, including games, videos, websites and texts, that can be used in bed and delay sleep, she said. They also emit audible notifications of incoming communications that may interrupt sleep.
"We found that both sleeping near a small screen and sleeping in a room with a TV set were related to shorter weekday sleep duration," Falbe noted. "Children who slept near a small screen, compared to those who did not, were also more likely to feel like they did not get enough sleep."
The findings were published online Jan. 5 and in the February print issue of the journal Pediatrics.
"Despite the importance of sleep to child health, development and performance in school, many children are not sleeping enough," Falbe said.
Preteen school-aged children need at least 10 hours of sleep each day, while teenagers need between nine and 10, the U.S. National Heart, Lung, and Blood Institute advises.
For this study, the researchers focused on the sleep habits of nearly 2,050 boys and girls who had participated in the Massachusetts Childhood Obesity Research Demonstration Study in 2012-2013.
The children were in the fourth or seventh grade in one of 29 schools. More than two-thirds of the children were white, and roughly one-fifth were Hispanic.
All were asked about electronic devices in the bedroom, what time they went to bed, what time they woke up, and how many days over the prior week they felt they needed more sleep.
While kids with a bedroom TV said they got 18 minutes less sleep on weeknights than those without a personal television, that figure rose to nearly 21 minutes for those who slept near a smartphone whether or not a TV was also present, the study found.
Going to bed with a smartphone at hand was also linked to later bedtimes than having a bedroom TV: 37 minutes later compared to 31 minutes, the investigators said.
And kids who slept with a smartphone were more likely to feel they needed more sleep than they were getting, compared with those with no smartphone present at bedtime. That perception of insufficient rest/sleep was not observed among children who only had a TV in the room.
So what's a 21st century parent to do?
Establishing technology ground-rules may help foster healthier sleep patterns, Falbe suggested.
For example, parents can set nighttime "curfews" for electronic devices, limit overall access to all screen time, and/or ban TVs and Internet-enabled devices from a child's bedroom, she said.
"While more studies are needed to confirm these findings, our results provide additional support for current recommendations of the American Academy of Pediatrics that parents should be advised to set reasonable but firm limits on their child's media use," Falbe said.
Dr. David Dunkin, an assistant professor of pediatrics at the Icahn School of Medicine at Mount Sinai in New York City, agreed.
"There is a lot of compelling data, in both adults and adolescents, that small screens disrupt sleep cycles," he noted. "And this may have an impact on long-term health. More studies need to be done to look at all of the variables together."
Meanwhile, he said, pediatricians should share and support the academy's advice when talking with parents about the presence of TVs and small screens.