Bromocriptine improves digit symbol substitution test scores in neuroleptic-treated chronic schizophrenic patients

Abstract

SummaryThe cognitive effects of bromocriptine (10 mg/day) in chronic neuroleptic-treated schizophrenic patients were studied in a 4-month trial. Ten neuropsychological variables were used for the evaluations. Nine patients and seven controls completed the study. They were tested three times: before the beginning of the study, and after 2 and 4 months of treatment. The results showed that treated patients globally performed significantly better than the controls (P < 0.05), and that the digit symbol substitution test was significantly improved (P < 0.03). The WAIS performance score was also significantly improved (P < 0.02). The picture arrangement test was improved, but did not reach significance (P < 0.07). Verbal tests were not improved. It therefore appears that addition of a D2 dopamine agonist in neuroleptic-treated patients can improve some of their cognitive functions. Two explanations can be proposed: i) bromocriptine decreases neuroleptic-induced motor side effects or ii) has an effect on a putative hypodopaminergic function in schizophrenia.