B O S T O N, Dec. 27, 2001 -- While most of us think of the typical Tourette's patient as the rare eccentric who barks obscenities and jerks their arms wildly, a recent study says much more subtle symptoms of Tourette's and related tic disorders are far more common than once thought.
According to the study published in the journal Neurology, mild tics such as lip puckering, eye rolling, head tossing, and nose scrunching are important clues to diagnosing other learning disabilities like attention deficit hyperactivity disorder, or ADHD, and obsessive compulsive disorder, or OCD.
"[Kids with mild tics] are at a higher risk for developing future school problems. This is a way of identifying children ahead of time so they can be monitored — a clue to how the child's brain is organized," says lead study author Dr. Roger Kurlan, director of the Tourette's Syndrome Clinic and the Cognitive and Behavioral Neurology Clinic at the University of Rochester in New York.
Tip of the Iceberg
To determine the prevalence of tics and Tourette's Syndrome in school-aged children, Kurlan looked at a group of 1,600 children in both regular and special education classrooms in Rochester.
Kurlan found that just under 20 percent of children in regular classes and up to 27 percent of children in special education classes showed signs of tics. His study also revealed a three percent incidence of Tourette's in the general population — a rate three to 30 times greater than previous estimates.
"People, including parents and doctors, thought Tourette's meant having severe symptoms, but these cases are just the tip of the iceberg. The vast majority of cases have extremely mild cases," says Kurlan.
Dr. Leon Dure, a child neurologist and director of the Pediatric Psychomotor Disorders Clinic at Children's Hospital in Alabama, says his own clinical experience corresponds with the new statistics.
Dure says that when he started the pediatric disorders clinic he guessed he would have very few patients. But now, he has over 700.
"A lot of children have transient tics during development, but pediatricians usually tell parents not to worry about it, it will go away, and it usually does."
Dure says the tic turns into a disorder if it lasts for longer than 12 months. And for tics to indicate Tourette's Syndrome, both vocal tics (eg, grunting, beeping, throat-clearing) and motor tics (eg, shoulder popping, eye rolling, blinking) must co-exist for longer than a year.
Tics Hold Clues
Experts caution that if a parent notices their child has a mild tic, there is little need for immediate alarm unless a learning disability is also suspected.
"You really don't need a treatment for tics, but they are a sign you should pay attention to as they may point to other things," says Kurlan.
Learning disabilities such as ADHD or OCD afflict between 50 percent and 70 percent of children with Tourette's Syndrome, and Kurlan says his study suggests that even mild tics alone, not necessarily Tourette's, may represent an "identifiable sign of an underlying brain developmental disorder that contributes to academic difficulties," or a barrier to learning.
And experts stress the most important thing for parents of children with tics to keep in mind is the impact on the child's life.
According to Dr. Glen Elliott, director of child and adolescent psychiatry, at University of California San Francisco, "Many children, especially boys, have transient tics, such as a cheek twitch or eye spasm, but that hardly is a disorder. What's needed is a sense of severity, a measure of to what extent the tics are producing distress to the child or parent or some such."