A recent US study from the University of California MIND Institute has shown that trajectories of autism symptoms severity can evolve during early childhood.
The study found that nearly 30 per cent of young children have less severe autism symptoms at six years than they did at aged three. In some cases, children lost their autism diagnoses entirely, University of California senior study author, Professor David Amaral said. “It is also true that some children appeared to get worse,” he said.
The study, published in the Journal of Autism and Developmental Disorder, looked at 125 children, 89 boys and 36 girls, on the spectrum and found that nearly half displayed a significant change in the level of their symptoms between the ages of three and six years. Girls tended to decrease in severity more than boys, and increase in severity less than boys. The study also found that children with higher IQs were more likely to see their symptoms decline.
While the symptoms of ASD are commonly considered to be stable throughout life, increasing evidence indicates that at least some individuals demonstrate substantial changes in the core features of ASD/and or comorbid conditions over time.
About 29 per cent of the children saw their severity decrease, with seven recording scores below the threshold for an autism diagnosis when they were reevaluated at aged six. Nearly 17 per cent of the children experienced an increase in severity and around 55 per cent exhibited stable symptoms, according to the findings.
Researchers said they were surprised to see that children whose symptoms increased over the time period studied displayed lower severity levels initially. They also observed different patterns for girls versus boys.
“We found that girls with autism decrease in severity more than boys and increase in severity less than boys during early childhood,” University of California, study author and research graduate, Einat Waizbard-Bartov said. A possible explanation for this difference may be due to an increasing number of girls compared to boys who, with age, have learned how to camouflage their symptoms, he said.
In addition, children with higher IQs were more likely to see their symptoms decline, the study found.
However, more research is needed to further understand what’s causing autism severity to change in some children.
“Unfortunately, it is not currently possible to predict who will do well and who will develop more severe autism symptoms and need different interventions,” Amaral said.
The study focused on two questions: Does the severity of austism symptoms change in individual children across early childhood? And, Was the amount or direction of change affected by initial severity levels, intervention intensity, sex, IQ or level of adaptive functioning?