title: Case study: comorbidity among Tourette's syndrome, autistic disorder, and bipolar disorder.
abstract: OBJECTIVE
  Several studies report a greater than expected concurrence for Tourette's syndrome (TS) with autistic disorder (AD). TS and bipolar disorder (BD) also may co-occur at a greater than expected rate. The authors assess whether there is a greater than expected concurrence for TS+AD+BD.
  
  
  METHODS
  Four patients who had at some time in their lives diagnoses of TS, AD, and BD were identified. Three of these had concurrent TS+AD+BD. Diagnoses were made according to DSM-III-R criteria. Each of these patients was living in North Dakota and was in the authors' care at the time of this study.
  
  
  RESULTS
  The point prevalence (risk) for concurrent TS+AD+BD in North Dakota is not less than 4.6 x 10(-6). The developmental sequence of syndromes in these four patients was AD, then TS and then BD. Data from the authors' previously published, population-based prevalence studies indicate that TS+AD+BD co-occur at a greater than chance expectation.
  
  
  CONCLUSIONS
  Common etiological factors may be involved in the greater than chance concurrence of TS+AD+BD.
authors.affiliation: Department of Neuroscience, University of North Dakota School of Medicine, Grand Forks, USA.
authors.forename: J
authors.initials: J
authors.lastname: Kerbeshian
authors.forename: L
authors.initials: L
authors.lastname: Burd
mesh_terms: D000293:Adolescent; D001321:Autistic Disorder / Q000175:diagnosis / Q000453:epidemiology* / Q000523:psychology; D001714:Bipolar Disorder / Q000175:diagnosis / Q000453:epidemiology* / Q000523:psychology; D002648:Child; D002675:Child, Preschool; D015897:Comorbidity; D003430:Cross-Sectional Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D009658:North Dakota / Q000453:epidemiology; D005879:Tourette Syndrome / Q000175:diagnosis / Q000453:epidemiology* / Q000523:psychology