(SALT LAKE CITY)—Children suspected of having autism spectrum disorder (ASD) appear to be getting earlier evaluations to identify the condition, a study of 4-year-olds in Utah and four other states has found. The research suggests that a national effort to have kids looked at when they are younger is working.
Early intervention is critical to help those with ASD lead fuller lives. The drive to identify children with ASD or developmental disabilities at younger ages gained momentum after a landmark 2007 study estimated that one in 152 U.S. children had ASD, a marked increase over previous years. Following the study, the American Academy of Pediatrics recommended every child be evaluated for autism at 18 and 24 months.
Led by researchers from the Centers for Disease Control and Prevention (CDC), five states in the Early Autism and Developmental Disabilities Network (Early ADDM)–Utah, Arizona, Wisconsin, New Jersey and Missouri–examined health and education records of 4- and 8-year-old children in 2010 who had ASD characteristics. Among 4-year-old children with a previous ASD diagnosis by a community provider, researchers found that the median age of their first evaluation was five months earlier for children born in 2006 compared to children born in 2002, at 27 months and 32 months, respectively.
The reduction in the median age of first comprehensive evaluation demonstrates significant progress toward the goal of improving early screening and identification of children with ASD, according to Deborah Bilder, M.D., University of Utah associate professor of child psychiatry and the study's second author.
The numbers also showed that on average across the five states, a much larger percentage of the 4-year-olds than 8-year-olds identified with ASD by Early ADDM (71.3 percent versus 42.6 percent) were evaluated before age 3. The Utah ADDM showed a similar trend: 70.4 percent of 4-year-olds identified with ASD compared with 32.6 percent of 8-year-olds identified with ASD had a comprehensive evaluation by age 3.
"This study was the first opportunity to see how well we are doing at identifying kids who show signs of autism or developmental disabilities at an earlier age," Bilder says. "Our findings should give policy makers the feedback they need to continue the effort to identify kids with ASD earlier and also to make adjustments in funding allotments, service planning and public policy where needed."
The study appeared online in the Journal of Developmental and Behavioral Pediatrics on Dec. 9, 2015.
Along with looking at the median age of when children were first evaluated, the study estimated that across the Early ADDM sites one in 75 4-year-olds and one in 48 8-year-olds had ASD. The higher prevalence among 8-year-olds is likely explained, in part, by the under-identification of ASD among preschool children, according to Bilder. "Some children are not recognized as having ASD until they enter the public school system or reach an age where their social deficits become more apparent when compared to their peers," she says. "This is also the first year we measured ASD prevalence among 4-year-olds and estimate that previously we missed at least 10 percent of children with ASD."
Early ADDM looked at de-identified health and education records of 58,467 4-year-olds and 56,727 8-year-olds in the five-state network. The study found a total of 783 4-year-olds and 1,091 8-year-olds with ASD.
In Utah, the ADDM surveys rely on data from the Utah Registry of Autism and Developmental Disabilities (URADD), funded by the Utah Department of Health.
For the current study, URADD researchers surveyed the records of 4-year-olds with ASD in Tooele County and part of Salt Lake County and identified 132 children with ASD. Prevalence of the disorder in Utah was estimated at one in 83 4-year-olds. The numbers also showed that male 4-year-olds in Utah were three times more likely to be diagnosed with ASD than females. The reason for the almost triple prevalence of ASD among males compared to females is not yet known. The ASD prevalence in Utah among Non-Hispanic whites was nearly 1½ times that of Hispanic children, which may be reflect differences in access to health and education services.
"This is the first study of 4-year-old children in Utah using ADDM methodology," Bilder says. "We look forward to reviewing data from our subsequent 2012 study year so that we may have a clear sense of trends in national and local ASD prevalence and evaluation practices."
Utah and the other states in 2010 Early ADDM are part of the larger Autism and Developmental Disabilities Monitoring Network (ADDM), an 11-site CDC consortium that tracks autism prevalence among the nation's 8-year-olds. Amanda Bakian, Ph.D., URADD director, co-investigator of Utah ADDM and assistant professor of psychiatry (biostatistics) also contributed to 2010 Early ADDM. Bilder also serves as co-investigator at URADD.