Tracking the brain growth of infants can predict the likelihood that they will be diagnosed with autism in their toddler years, according to new research that could give doctors a head start on treating the developmental disorder.
The study, published Wednesday in the prestigious journal Nature, took place at four U.S. hospitals and was co-authored by two University of Minnesota researchers.
Children with autism often show hints of the disorder by their first birthdays, such as failing to make eye contact or respond to their names. But studies haven't proven these early behaviors to be reliable predictors, said co-author Jed Elison, an assistant professor in the U's Institute of Child Development. Most children aren't diagnosed until age 2 or older, when clear behavioral signs emerge.
"What really differentiates this work [is] the accuracy with which we can make a prediction," Elison said. "We're generating a prediction before the signs of autism can be observed, which is really groundbreaking."
Autism, or autism spectrum disorder, refers to a broad range of brain development abnormalities that cause patients to struggle with learning, social interaction and verbal and nonverbal communication.
The U.S. Centers for Disease Control and Prevention estimate that one in 68 children meet criteria for ASD, a rate that has increased sharply in recent years due partly to rising prevalence but also to a broadening clinical definition of the disorder.
Studies have shown that earlier intervention can reduce autism's severity because of the "plasticity" of the brain at an early age, which can make it particularly receptive to cognitive and communication training, Elison said. "The earlier an intervention is implemented, the better the outcome for kids with autism ... This has been a finding since the '70s."
Using magnetic resonance imaging (MRI), researchers took brain scans at 6 months, 12 months and 24 months of children who were at high risk for autism because their older siblings had the disorder. They then identified physical differences in the brains of the children in the group who actually developed autism, and applied those findings to a second group of high-risk children.