Article type
Year
Abstract
Introduction: Risperidone is a 'new', 'atypical' anti-psychotic. It is claimed that it differs from the older 'conventional' anti-psychotics in its reduced tendency to cause extra-pyramidal side effects and also the possibility that it may alleviate the negative symptoms of schizophrenia.
Objective: The primary objective was to systematically review the evidence from randomized controlled trials comparing the effectiveness of risperidone with: (i) placebo; (ii) conventional neuroleptic drugs; and (iii) atypical neuroleptics. The effectiveness of rispcridone for those with (a) treatment resistant schizophrenia and (b) first episode schizophrenia was also examined.
Methods: A comprehensive search was undertaken in order to identify as fully as possible all available randomized controlled trials, both published and unpublished. Trials were located by searching commercial databases such as medline and embase, the Cochrane Schizophrenia Groups Register of randomized controlled trials, reference lists of articles and by approaching pharmaceutical companies directly to obtain data on unpublished trials. All included trials were evaluated on the basis of three quality categories as described in the Cochrane Collaboration Handbook. Only trials in category A or B were included in the review. Data from all identified and selected trials was entered into a funnel graph (trial effect vs trial size) in an attempt to investigate the likelihood of overt publication bias. Data was independently extracted by two reviewers. For dichotomous outcomes, an 'odds ratio' (OR) with the confidence interval around this was estimated. As a measure of efficiency the number needed to treat statistic was also calculated. Where continuous data was presented from different scales rating the same effect, both sets of data were presented, the general direction of effect inspected and the 'effect size' statistic calculated. An intention to treat analysis was carried out.
Results: Results will focus on four main areas of interest: (i) clinically significant improvement in mental state with particular reference to the positive and negative symptoms of schizophrenia; (ii) side effects, but particularly extra-pyramidal side effects and those side effects considered to occur commonly with risperidone i.e. anxiety, agitation, insomnia and headache; (iii) acceptability of treatment both as assessed directly by questioning trial participants and indirectly by numbers dropping out from studies; (iv) relapse as defined in individual studies.
Discussion: This systematic review provides a reliable overview of the available evidence regarding the efficacy and side effect profile of risperidone as well as clarifying areas where further research is needed.
Objective: The primary objective was to systematically review the evidence from randomized controlled trials comparing the effectiveness of risperidone with: (i) placebo; (ii) conventional neuroleptic drugs; and (iii) atypical neuroleptics. The effectiveness of rispcridone for those with (a) treatment resistant schizophrenia and (b) first episode schizophrenia was also examined.
Methods: A comprehensive search was undertaken in order to identify as fully as possible all available randomized controlled trials, both published and unpublished. Trials were located by searching commercial databases such as medline and embase, the Cochrane Schizophrenia Groups Register of randomized controlled trials, reference lists of articles and by approaching pharmaceutical companies directly to obtain data on unpublished trials. All included trials were evaluated on the basis of three quality categories as described in the Cochrane Collaboration Handbook. Only trials in category A or B were included in the review. Data from all identified and selected trials was entered into a funnel graph (trial effect vs trial size) in an attempt to investigate the likelihood of overt publication bias. Data was independently extracted by two reviewers. For dichotomous outcomes, an 'odds ratio' (OR) with the confidence interval around this was estimated. As a measure of efficiency the number needed to treat statistic was also calculated. Where continuous data was presented from different scales rating the same effect, both sets of data were presented, the general direction of effect inspected and the 'effect size' statistic calculated. An intention to treat analysis was carried out.
Results: Results will focus on four main areas of interest: (i) clinically significant improvement in mental state with particular reference to the positive and negative symptoms of schizophrenia; (ii) side effects, but particularly extra-pyramidal side effects and those side effects considered to occur commonly with risperidone i.e. anxiety, agitation, insomnia and headache; (iii) acceptability of treatment both as assessed directly by questioning trial participants and indirectly by numbers dropping out from studies; (iv) relapse as defined in individual studies.
Discussion: This systematic review provides a reliable overview of the available evidence regarding the efficacy and side effect profile of risperidone as well as clarifying areas where further research is needed.