Switching from therapy with typical antipsychotic agents to risperidone: long-term impact on patient outcome

This paper reports the results of a retrospective, open-label study in 31 schizophrenic patients who had been switched from therapy with a typical antipsychotic agent to risperidone, a novel antipsychotic agent, in the course of their treatment in an outpatient/community program. The study was based on both a review of all 31 patients' charts and a structured interview of 26 of the patients. The change to risperidone had been made because of lack of efficacy or intolerance to typical antipsychotic agents after a mean of 3.5 years of therapy. Patients had been maintained on risperidone for a mean of 1.7 years at the time of the review. The impact of switching to risperidone was assessed by comparing clinical variables for the patients with their own historic control data. The current levels of symptoms, side effects, and social functioning were also assessed by means of the Interview for Retrospective Assessment of Onset of Schizophrenia and rating scales. Seventy-one percent and 81% of the patients exhibited a positive response, as measured by a 30% reduction in psychotic and disorganization syndromes, respectively. After the switch, significant declines were noted in service utilization; the level of psychotic, disorganization, and negative symptom dimensions; and the use of anticholinergic drugs (P < 0.01 for all). Assessments conducted at the time of the review revealed a low level of psychotic (mean, 3.5) and disorganization (mean, 3.0) symptoms, a moderate level of negative symptoms (mean, 19.5), and a low level of extrapyramidal symptoms (total mean parkinsonism score, 6.0). No significant changes were seen in the level of employment or in living conditions. Results of this study suggest that a switch to risperidone therapy because of the inefficacy of typical antipsychotic agents or patients' inability to tolerate them may lead to sustained and significant improvement in a substantial proportion of patients with schizophrenia.