No increased risk of ASD diagnosis seen, however

A study first reported in April suggests that too much screen time combined with too little time playing with parents may contribute the symptoms of autism in toddlers but didn’t appear to increase autism risk. Deciphering the autism puzzle is always challenging, so BreakingMED adds this report—originally published on April 20, 2020— to its year-end clinical review series.

More screen time and less play with parents at age 12 months were both associated with more autism-spectrum-disorder (ASD) symptoms at age 2, though not ASD risk, an observational cohort study found.

Television or video viewing at 12 months was associated with about 4% greater ASD-like symptoms at 2 years, according to David Bennett, PhD, of Drexel University in Philadelphia, and coauthors. Daily play with parents (versus less than daily play time) was associated with about 9% fewer ASD-like symptoms at 2 years of age, they reported in JAMA Pediatrics.

The study found associations only with ASD-like symptoms, not ASD risk. Screen exposures at 18 months were not significantly associated with ASD-like symptoms or ASD risk at 2 years.

“This cohort study found greater screen exposure and less caregiver-child play early in life to be associated with later ASD-like symptoms,” Bennett and coauthors wrote. “This outcome is an important area of research because these factors are potentially modifiable through parental education.”

“We suggest that pediatricians thoroughly educate parents regarding the American Academy of Pediatrics (AAP) recommendations to avoid screen viewing in children younger than 18 months,” they added.

In an accompanying editorial, Dimitri Christakis, MD, MPH, of the Seattle Children’s Research Institute, noted that while further study is imminent (the NIH-supported Healthy Brain and Child Development Study is preparing to launch), “waiting for answers 5 to 7 years before acting is hardly helpful to those with young children at present.”

For now, Christakis suggested that parents and clinicians “follow Hippocrates’ mantra to first do no harm. The American Academy of Pediatrics Media and Young Minds statement recommends no digital media before 18 months of age, given the absence of demonstrable benefits and the theoretical and limited empirical suggestion of harm,” he wrote. “This study adds additional credence to those recommendations.”

ASD prevalence in 2-year surveillance reporting shows rates of 1/150 for the 2000 surveillance period (birth year 1992) and 1/54 for the 2016 surveillance period (birth year 2008). Screen time in infants and young children has also been increasing, with evidence that preschoolers accumulate screen time at home, child care, and school from both directly attended and ambient screens, and that in the U.S. children between 8 months and 8 years experience 4 hours of background TV daily. Associated negative effects have included difficulties with self-regulation and behavioral issues as well as obesity.

In this setting of increasing prevalence of ASD and increasing screen exposure of infants, one study found an association between early viewing of baby DVDs/videos and poor language development on a score of language skills including vocabulary, grammar, and sentence length and complexity, but a second analysis of the same data suggested the original analysis was ambiguous. Screen time exposure consists of more than content and time, though: an analysis of infant and toddler DVDs found they feature rapid pacing and camera cuts, with minimal reflective features to provide opportunities to rehearse content.

Bennett and colleagues added to this emerging field, focusing on exposures during the first 12 to 18 months and rating ASD-like symptoms at 2 years. Data came from the completed National Children’s Study (NCS), a U.S. multicenter study of environmental influences on child health and development that enrolled 2,152 children at birth from October 2010 to October 2012. About half of the children in the sample (51%) were male.

Caregivers reported screen viewing and parental play time data when infants were 12 months old and provided screen exposure information again when children were age 18 months. Depending on the date of evaluation, researchers assessed ASD-like symptoms and risk with the autism screening tool Modified Checklist for Autism in Toddlers or a revised version (M-CHAT-R).

Television or video viewing, compared with no viewing, at 12 months was associated with greater ASD-like symptoms at 2 years (change 4.2%; 95% CI 0.1%-8.3%), but not ASD risk (risk prevalence rates 8.3% versus 4.4%; adjusted OR 1.40; 95% CI 0.86-2.29).

Meanwhile, daily play with parents, compared with less than daily play, was associated with fewer ASD-like symptoms at 2 years of age (change −8.9%; 95% CI −16.5% to −0.9%), but not ASD risk (risk prevalence rates 6.4% vs 14.0%; adjusted OR 0.58; 95% CI 0.31-1.08).

“We also found prematurity, minority race/ethnicity, and lower family income to be associated with greater ASD risk and ASD-like symptoms on the M-CHAT, adding to the literature regarding perinatal and demographic risk factors,” the researchers noted.

Limitations include an absence of detailed information about the screen exposure content. “After 1 year of age, we know how much media children in the NCS watched, but not what they watched,” the editorialist observed.

“Diminished interactions with caregivers because of time spent with media likely exert greater effects before 1 year of age,” he added. “Also, sample size may have reduced the power to detect diagnoses of ASD rather than symptoms of it.”

Paul Smyth, MD, Contributing Writer, BreakingMED™

This study used National Children’s Study (NCS) research materials obtained from the NCS Vanguard Data and Sample Archive and Access System and does not necessarily reflect the opinions or views of the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) or the National Institutes of Health.

The researchers reported no conflicts of interest.

The editorialist reported being a member of the scientific advisory board for Children and Screens: Institute of Digital Media and Child Development, a not-for-profit foundation.

Cat ID: 135

Topic ID: 85,135,730,128,130,135,138,192,925

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