[Long-term effects of the treatment with risperidone versus conventional neuroleptics on the neuropsychological performance of euthymic bipolar patients].

INTRODUCTION: An increasing number of studies point to the persistence of cognitive deficits in a subpopulation of euthymic bipolar disorders. Atypical antipsychotics represent an interesting alternative treatment compared with conventional neuroleptics, because the former might cause lesser affection of cognitive functions. The objective of this study was to establish, for euthymic bipolar patients who need long-term antipsychotic treatment, the neuropsychological and outcome (occupational functioning) differences between the patients treated with risperidone and the patients treated with conventional neuroleptics.

SUBJECTS AND METHOD: A sample of twenty RDC bipolar I and II patients were assessed by means of the SADS. All of them were euthymic (HDRS < 8; YMRS < 6) for at least 6 months and treated with antipsychotics. Patients who received risperidone (N = 11) were compared with patients who received conventional neuroleptics (N = 9) with respect to their neuropsychological profile.

RESULTS: There were significant differences in Trail Making Test-part B (p = 0.038) and in occupational outcome (p = 0.024), favouring patients who were treated with risperidone. There were no significant differences in other neuropsychological tests, but the patients treated with risperidone tended to score higher in most measures of cognitive performance.

CONCLUSIONS: Among bipolar patients who need long-term antipsychotic treatment for preventing relapses, patients who receive risperidone show more cognitive flexibility and better occupational adaptation than patients treated with conventional neuroleptics.