Case study: comorbidity among Tourette's syndrome, autistic disorder, and bipolar disorder.

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.

METHOD

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.