Search

Risperidone has been shown to improve verbal working memory, executive functioning, attention, reaction time, and verbal learning, which, in turn, have been associated with improved functional outcomes. We tested whether risperidone was associated with greater improvements than haloperidol in activities of daily living (ADLs) among persons having treatment-refractory schizophrenia. In a double-blind, controlled trial of fixed and flexible doses of haloperidol and risperidone, changes in ADLs were operationally monitored on a behavior therapy unit of a state hospital. While no differential effects were noted between risperidone and haloperidol in ADLS, these self-care skills significantly improved as subjects spent longer times on the behavior therapy unit. Working memory and verbal learning did correlate with improvements in ADLs, independent of drug condition. The contingencies of reinforcement and specific training programs on the behavior therapy unit may have been prepotent for the learning of ADLs, obscuring any differential impact of risperidone. Moreover, ADLs may be governed more by "procedural" learning than by working memory or verbal learning, with the former not differentially influenced by typical verus atypical antipsychotics., (Copyright 2002, Elsevier Science (USA). All rights reserved.)

Objective: The purpose of this study was to evaluate the clinical safety and efficacy of risperidone compared to haloperidol in patients with treatment-refractory schizophrenia., Method: Sixty-seven medication-unresponsive subjects were randomly assigned to treatment with risperidone (N = 34) or haloperidol (N = 33). After a 3-7 day-placebo washout period, there was a 4-week, double-blind, fixed-dose comparison trial that was followed by a 4-week, flexible-dose phase. Measures of clinical change were quantified by standard psychopathologic and neuromotor instruments., Results: Risperidone demonstrated clinical efficacy superior to that of haloperidol on the total Brief Psychiatric Rating Scale (BPRS) after the first 4 weeks of treatment. Risperidone did not show any advantage over haloperidol after an additional 4 weeks. Overall improvement on the BPRS at 4 weeks was significantly better for the risperidone group (24%) than for the haloperidol group (11%). Risperidone-treated subjects were significantly less likely than haloperidol-treated subjects to require concomitant anticholinergic medication after 4 weeks (20% versus 63%); they also had significantly les observable akathisia (24% versus 53%) and significantly less severe tardive dyskinesia. Baseline characteristics that correlated significantly with risperidone response were positive symptoms, conceptual disorganization, akathisia, and tardive dyskinesia., Conclusions: Risperidone was better tolerated and more effective in a subset of patients with treatment-refractory schizophrenia. Positive psychotic symptoms and extrapyramidal side effects at baseline appear to be powerful predictors of subsequent response to risperidone.

The introduction of the new generation of antipsychotic medications for the treatment of schizophrenia has been accompanied by a growing interest in the neurocognitive effects of these drugs. The present study compared the effects of risperidone and haloperidol on secondary memory in a group of treatment-resistant schizophrenia patients. The study design included a baseline phase and two double-blind phases in which patients were randomly assigned to medication under two different dose conditions (fixed dose and flexible dose). Secondary memory was assessed at baseline, fixed-dose, and flexible-dose phases, using the California Verbal Learning Test (CVLT). Six measures were selected, which formed three factors (general verbal learning ability, retention, and learning strategy). Risperidone-treated patients showed greater improvement than haloperidol-treated patients in general verbal learning ability, a finding characterized by significant treatment effects on CVLT measures of learning acquisition, recall consistency, and recognition memory. After controlling for benztropine status, differences on the measures of learning acquisition and recall consistency remained significant, and differences in recognition memory weakened slightly (p = 0.07). No significant treatment effects were noted on retention or learning strategy. These findings suggest that risperidone may exert a facilitating effect on the acquisition of new verbal information, an effect that does not appear to be due to the activation of semantic encoding strategies.

Background: The present study compared the effects of risperidone vs. haloperidol on reaction time, manual dexterity, and two types of motor learning in a sample of treatment-resistant schizophrenia patients., Methods: Fifty-six DSM-III-R diagnosed schizophrenia inpatients participated in a randomized, double-blind comparison of risperidone vs. haloperidol. Measures of reaction time, manual dexterity, motor sequence learning, and gross motor learning were administered at baseline, after 4 weeks of fixed-dose medication, and after 4 weeks of flexible-dose medication., Results: The results indicated that patients receiving risperidone showed greater improvement in reaction time and manual dexterity than patients receiving haloperidol. After covarying symptom changes and movement disorder ratings, the results remained significant. The two treatment groups did not differ on either measure of motor learning., Conclusions: The differences in performance in reaction time and manual dexterity may be due to a specific beneficial effect of risperidone, as opposed to a general reduction in extrapyramidal symptom liability, compared to haloperidol.

Currently, little is known about the pharmacological effects of the new generation of antipsychotic medications on perception of emotion in schizophrenia. The present study was designed to compare the effects of risperidone versus haloperidol on the ability to perceive emotion in 20 treatment-resistant schizophrenia patients, using a double-blind design. Measures of emotion perception included a facial emotion identification test (still photographs presented on videotape), a voice emotion identification test (audiotape), and an affect perception test (brief interpersonal vignettes presented on videotape). These measures were administered during the final week of baseline and after 8 weeks of double-blind medication. Risperidone treatment produced a greater effect on patients' ability to perceive emotion compared with haloperidol treatment. Additionally, all patients who received risperidone demonstrated improvement in performance between baseline and retest, compared with four of the nine patients who received haloperidol. When changes in positive symptoms were statistically controlled, the results remained significant. These findings suggest that resperidone may facilitate patients' ability to accurately perceive emotion, an effect which may be mediated either directly by risperidone's pharmacological action or perhaps indirectly by its influence on basic neurocognition.

Objective: Treatment efficacy in schizophrenia is typically defined in terms of symptom reduction. However, new antipsychotic medications could potentially have an impact on aspects of disability, such as neurocognitive deficits. The authors evaluated the effects of risperidone on verbal working memory, a memory component of theoretical interest because of its link to prefrontal activity and of practical interest because of its link to psychosocial rehabilitation., Method: Verbal working memory of 59 treatment-resistant schizophrenic patients was assessed as part of a randomized, double-blind comparison of treatment with risperidone and haloperidol. Verbal working memory was measured under both distracting and nondistracting conditions at baseline and after 4 weeks of both fixed- and flexible-dose pharmacotherapy., Results: Risperidone treatment had a greater beneficial effect on verbal working memory than haloperidol treatment across testing conditions (with and without distraction) and study phases (fixed and flexible dose). The treatment effect remained significant after the effects of benztropine cotreatment, change in psychotic symptoms, and change in negative symptoms were controlled. Neither benztropine status nor symptom changes were significantly related to memory performance., Conclusions: Treatment with risperidone appears to exert a more favorable effect on verbal working memory than treatment with a conventional neuroleptic. The beneficial effect appears to be due, at least partially, to a direct effect of the drug, possibly through antagonism of the 5-HT2A receptor. Results from this study suggest that pharmacotherapeutic efficacy in schizophrenia treatment could be broadened to include impact on neurocognitive abilities.