Rates of autism spectrum disorder (ASD) are not creeping up so much as leaping up. New numbers just released by the Centers for Disease Control and Prevention reveal that one in 68 children now has a diagnosis of ASD—a 30 percent increase in just two years. In 2002, about one in 150 children was considered autistic and in 1991 the figure was one in 500.
The staggering increase in cases of ASD should raise more suspicion in the medical community about its misdiagnosis and overdiagnosis than it does. Promoting early screening for autism is imperative. But, is it possible that the younger in age a child is when professionals screen for ASD—especially its milder cases—the greater the risk that a slow-to-mature child will be misperceived as autistic, thus driving the numbers up?
The science stacks up in favor of catching and treating ASD earlier because it leads to better outcomes. Dr. Laura Schreibman, who directs the Autism Intervention Research Program at the University of California, San Diego embodies the perspective of most experts when she says, “Psychologists need to advise parents that the ‘wait-and-see’ approach is not appropriate when ASD is expected. Delaying a diagnosis can mean giving up significant gains of intervention that have been demonstrated before age six.”
There is a universal push to screen for ASD at as young an age as possible and growing confidence that the early signs are clear and convincing. Dr. Jose Cordero, the founding director of the National Center on Birth Defects and Developmental Disabilities conveys this fervor.
"For healthcare providers, we have a message that's pretty direct about ASD. And the message is: The 4-year-old with autism was once a 3-year-old with autism, which was once a 2-year-old with autism."
Many researchers are now on the hunt for atypical behaviors cropping up in infancy that could be telltale signs of ASD. For instance, a team of experts led by Dr. Karen Pierce at the Autism Center of Excellence at the University of California, San Diego, has used eye-tracking technology to determine that infants as young as 14 months who later were diagnosed as autistic showed a preference for looking at movies of geometric shapes over movies of children dancing and doing yoga. This predilection for being engaged by objects rather than "social" images is thought to be a marker for autism.
Even the quality of infants' crying has come under scientific scrutiny as a possible sign of the disorder. Dr. Stephen Sheinkopf and some colleagues at Brown University compared the cries of a group of babies at risk for autism (due to having an autistic sibling) to typically developing babies using cutting-edge acoustic technology. They discovered that the at-risk babies emit higher-pitched cries that are "low in voicing," which is a term for cries that are sharper and reflect tense vocal chords. Dr. Sheinkopf, however, cautioned parents against over-scrutinizing their babies' cries since the distinctions were picked up by sophisticated acoustic technology, not by careful human listening.
"We definitely don't want parents to be anxiously listening to their babies' cries. It's unclear if the human ear is sensitive enough to detect this."
What gets lost in the debate is an awareness of how the younger in age we assess for problems, the greater the potential a slow-to-mature kid will be given a false diagnosis. In fact, as we venture into more tender years to screen for autism, we need to be reminded that the period of greatest diagnostic uncertainty is probably toddlerhood. A 2007 study out of the University of North Carolina at Chapel Hill found that over 30 percent of children diagnosed as autistic at age two no longer fit the diagnosis at age four. Since ASD is still generally considered to be a life-long neuropsychiatric condition that is not shed as childhood unfolds, we have to wonder if a large percentage of toddlers get a diagnosis that is of questionable applicability in the first place.
The parallels between a slow-to-mature toddler and a would-be-mildly- autistic one are so striking that the prospect of a false diagnosis is great. Let's start with late talkers. Almost one in five 2-year-olds are late talkers. They fall below the expected 50-word expressive vocabulary threshold and appear incapable of stringing together two- and three-word phrases.
Data out of the famed Yale Study Center have demonstrated that toddlers with delayed language development are almost identical to their autistic spectrum disordered counterparts in their use of eye contact to gauge social interactions, the range of sounds and words they produce, and the emotional give-and-take they are capable of. Many tots are in an ASD red-zone who simply don't meet standard benchmarks for how quickly language should be acquired and social interactions mastered.
Expanding autistic phenomena to include picky eating and tantrums can create more befuddlement when applied to small children. Several years ago a study published in the Journal of the American Dietetic Association tracking over 3,000 families found that 50 percent of toddlers are considered picky eaters by their caregivers. The percentage of young children in the U.S. who are picky eaters and have poor appetites is so high that experts writing in the journal Pediatrics in 2007 remarked, " … it could reasonably be said that eating-behavior problems are a normal feature of toddler life."