Tourette syndrome and chronic tics in a sample of children and adolescents.

Forty-eight subjects with Tourette syndrome (M 36, F 12; mean age 11.2 years) and 48 with chronic tic disorder (M 33, F 15; mean age 12.1 years) were recruited in order to study the vertical transmission within families of a vulnerability to tic disorders or to other psychiatric disorders, the role of adverse pre- and perinatal events, and the presence of comorbid psychiatric conditions. As control group, 30 matched, psychiatrically unaffected subjects (M 20, F 10; mean age 10.8 years) were chosen. Screening measures included detailed anamnestic data, focused on family history of tics and other psychiatric disorders, prenatal events and birth. Subjects and parents were also questioned about psychiatric comorbidity. Group differences were compared using Fisher Test. Subjects with Tourette syndrome and those with chronic tic were similar to each other and different from controls in family history of tic disorders, pre- and perinatal events, and some comorbid psychiatric disorders (attention deficit hyperactivity disorder, sleep problems, and mood disorders). Tourette syndrome and chronic tic group were different in family history of obsessive-compulsive disorder and in comorbidity for obsessive-compulsive disorder and other anxiety disorders. Tourette syndrome and obsessive-compulsive disorder were significantly associated in this sample. These findings seem to indicate that Tourette syndrome and chronic tic disorder are part of the same disease entity, with Tourette syndrome being a more severe and complex form of tic disorder.