Being able to predict which adolescents will develop schizophrenia could make an enormous difference in their prognosis, given the fact that antipsychotic drugs can prevent the disorder from taking hold.
Past studies have shown that from 20 to 40 percent of young people with a disorder called schizotypal personality disorder (SPD) will develop schizophrenia within a few years of their diagnosis. But that's too low an average to prescribe them all with medications that often have severe side effects.
Now, researchers at Emory University say they are one step closer to finding a tool that will predict adolescents' risk for schizophrenia. A study, published in the May issue of the Journal of Abnormal Psychology (Vol. 116, No. 2), shows that adolescents with SPD display more abnormal motor movements-including facial tics and finger writhing than adolescents who do not suffer from SPD. In addition, the more severe the motor abnormalities, the more severe the symptoms of SPD were, and the more likely the psychotic symptoms would worsen a year later.
The link between motor function and psychosis is not new, but this is the first study to look at the progression of symptoms over time, according to one of the study's lead authors Elaine Walker, PhD, at Emory University. Earlier work by Walker and others has linked motor abnormalities to psychosis and suggested that the brain regions that are linked to motor circuits may also give rise to psychotic symptoms.
This new study, Walker says, further documents that adolescence is a key period for the emergence of mental disorders-and, therefore, a critical time to identify and treat people. She cautions, however, that because of antipsychotics' adverse side effects, they should be prescribed only once researchers can more accurately identify people at high risk.
"We haven't reached that point yet," she says, adding that it will likely take a "constellation of risk indicators" to make accurate predictions.