Study finds racial gap in Tourette's
ATLANTA - Tourette's syndrome occurs in 3 out of every 1,000 school-age children, and is more than twice as common in white children as in blacks or Hispanics, according to the largest US study to estimate how many have the disorder.
Tourette's - known for its physical tics and, in some cases, shouted obscenities - has long been considered a rare condition. The new number means it's more common than some past estimates, but confirms that it's far less common than other neurological conditions such as autism or attention deficit hyperactivity disorder.
The racial gaps are probably the most surprising finding, the study's authors said.
"Prior to this, we really had very little information about minorities," said Lawrence Scahill, a Yale University researcher. The study was released yesterday.
It's not clear why whites have a higher rate or whether future studies will find the same disparity, specialists said. Some suspect it has less to do with genetics than with a difference in access to medical care or in attitudes about whether repetitive blinking or other tics require medical care.
The study, led by the Centers for Disease Control and Prevention, estimates there are about 150,000 US children with Tourette's. The researchers also found that:
Most cases were mild, but 1 in 4 were - in the parent's opinion - moderate or severe.
Boys had a rate three times higher than girls.
About 80 percent had been diagnosed with another mental illness or developmental disability.
The report is being published this week in CDC's Morbidity and Mortality Weekly Report.