Kids with a genetic risk for autism spectrum disorder (ASD) are likely to spend hours a day glued to their screens, but researchers say it doesn't mean screen time causes ASD.
The investigators also found that children with attention-deficit/hyperactivity disorder (ADHD) gradually increased their screen time as they got older, even if they started out with low levels of initial screen use.
"While long periods of screen time in childhood have been suggested to be a cause of ASD/ADHD, the results of this study suggest that some people may have a genetic disposition to use screens because of ASD,"said lead researcher Dr. Nagahide Takahashi. He is an associate professor of medicine at Nagoya University in Japan.
"Screen time may be an early sign of ASD, rather than a cause, as children with ASD are often more attracted to objects than people," he added in a university news release.
"Physicians should know that it is not fair to conclude that prolonged screen time is a risk factor for the development of ASD,"Takahashi explained.
Most people are spending more time on digital devices, including smartphones, computers, television and video game systems. The researchers said that's especially true for kids with neurodevelopmental disorders.
Joining with colleagues from Hamamatsu University, Takahashi's team examined 6.5 million differences in the DNA of 437 children to determine genetic susceptibility to ASD and ADHD.
The investigators then calculated a genetic risk index that considers the number and size of effects of changes in genes associated with ASD/ADHD.
That index was then compared with how much time a group of young children aged 18, 32 and 40 months of age spent using devices with screens.
The researchers found that kids with a higher genetic susceptibility to ASD used devices with screens longer from early childhood -- as much as 4-plus hours a day. They also found that kids with ADHD used screens more and more as they got older.
"Overall, those with a genetic risk of ASD were 1.5 times more likely to be in the group with about three hours of screen time per day, and 2.1 times more likely to be in the group with more than four hours of screen time,"Takahishi said.
Takahashi cautioned against overexposing children with ADHD to screens.
"Our results suggest that children at risk of ADHD are at risk of having too much screen time, especially since gaming addiction is common,"he said. "As screen time tends to be longer for children who are particularly susceptible to ADHD, parents and caregivers should be cautious about it and make a commitment before it becomes a problem."
Takahashi said the findings, published recently in the journal Psychiatry Research, may help parents manage kids' behavior.
"Parents of children with neurodevelopmental disorders may feel guilty or be criticized by others for allowing their children screen time,"he said. "However, we would recommend offering help to caregivers, including offering alternative behavioral management strategies."
More information
The U.S. Centers for Disease Control and Prevention has more on autism spectrum disorder.
SOURCE: Nagoya University, news release, Oct. 26, 2023
