Tourette's syndrome in a special education population: a pilot study involving a single school district.

To determine whether children requiring special education represent a high-risk group for identifying Tourette's syndrome (TS), we performed direct examinations for the presence of tics in 35 special education and 35 regular classroom students from a single school district. Of the special education students, nine (26%) had definite or probable tics as compared with only two (6%) of the regular classroom students. About one-third of the students with tics currently meet diagnostic criteria for TS and probably more will do so in the future. About one-half of the subjects with tics have evidence of obsessive-compulsive behavior (OCB) or an attention-deficit hyperactivity disorder (ADHD). For three randomly selected students with definite tics, direct examinations of first-degree relatives revealed the presence of tics in all families. Subjects to the limitations of this pilot study, we conclude that TS and related tic disorders are commonly associated with the need for special education in this single school district. TS might also be an important contributor to school problems in the childhood population at large and may be a highly prevalent condition. In addition, we conclude that childhood tics are associated with OCB and ADHD, are genetically determined, and are part of the TS clinical spectrum.