Bipolar disorder and dopamine dysfunction: an indirect approach focusing on tardive movement syndromes in a naturalistic setting.

BACKGROUND

It has been suggested that dopamine dysfunction may play a role in bipolar disorder (BD). An indirect approach to examine this issue was developed, focusing on associations between dopamine proxy measures observed in BD (dopamine-related clinical traits using tardive movement syndromes as dopamine proxy measure of reference).

METHODS

3459 eligible bipolar patients were enrolled in an observational study. Incidence rates of tardive movement syndromes (tardive dyskinesia and tardive dystonia; TDD) were examined. A priori hypothesized associations between incident TDD and other dopamine proxies (e.g. prolactin-related adverse effects, bipolar symptoms) were tested over a 2 year follow-up period.

RESULTS

The incidence rate of tardive syndromes was 4.1 %. Incident TDD was independently associated not only with use of antipsychotics, but also with more severe bipolar symptoms, other extrapyramidal symptoms and prolactin-related adverse effects of medication.

CONCLUSION

Apart from the well-known association with antipsychotics, development of TDD was associated with various other dopamine proxy measures, indirectly supporting the notion of generalised dopamine dysregulation in BD.