An international perspective on Tourette syndrome: selected findings from 3500 individuals in 22 countries

We have established a multisite, international database of 3500 individuals diagnosed with Tourette syndrome (TS), The male:female ratio is 4.3:1 for the total sample, with wide variation among sites; the male excess occurs a t every site. Anger control problems, sleep difficulties, coprolalia, and s elf-injurious behavior only reach impressive levels in individuals with com orbidity, Anger control problems are strongly correlated with comorbidity, regardless of site, region, or whether assessed by neurologists or psychiat rists, The mean age at onset of ties is 6.4 years. At all ages, about 12% of indiv iduals with TS have no reported comorbidity. The most common reported comor bidity is attention-deficit-hyperactivity disorder. Males are more likely t o have comorbid disorders than females. The earlier the age at onset, the g reater the likelihood of a positive family history of ties. An understandin g of the factors producing these and other variations might assist in bette r subtyping of TS. Because behavioral problems are associated with comorbid ity, their presence should dictate a high index of suspicion of the latter, whose treatment may be at least as important as tie reduction, The establi shed database can be used as the entry point for further research when larg e samples are studied and generalizability of results is important.