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Georges Gharabawi

Publications and source records attributed to Georges Gharabawi.

10 recordsLinked to original sources
PubMed2007

Risperidone and cognitive function in children with disruptive behavior disorders.

BACKGROUND: Effects of risperidone on cognitive function in children with disruptive behavior disorders (DBDs) and subaverage intelligence quotient (IQ) were assessed. METHODS: Data from two 6-week, double-blind, placebo-controlled studies (n = 228) were combined, as were three 1-year, open-label studies (n = 688). Patients with DBDs and subaverage IQ, 5 to14 years, received placebo or risperidone .02 to .06 mg/kg/day. Cognitive measures included the Continuous Performance Task (CPT) and Verbal Learning Test for Children (VLT-C). Efficacy was assessed using the Nisonger Child Behavior Rating Form (NCBRF). Adverse events were collected via spontaneous report; sedation was assessed using visual analog scale. RESULTS: Improvements on the NCBRF Conduct Problem subscale were significantly greater for risperidone- versus placebo-treated patients (-15.8 vs. -6.4, p < .0001) in short-term studies; significant reductions were observed in long-term studies (-16.3, p < .0001). No overall decline and some significant improvement in attention (CPT) and memory (VLT-C) were noted regardless of treatment in short-term studies. VLT-C improved significantly (p < .0001) for both groups, with no difference between treatment groups. Improvements in memory (VLT-C) and attention (CPT) were noted in long-term studies. Somnolence/sedation did not affect cognitive function. CONCLUSIONS: Cognitive function was not altered by risperidone in short-term studies and was maintained or improved with one year of treatment in children with DBDs and subaverage IQ, potentially representing age-appropriate gains.

Adolescent↗
PubMed2006

A model of anticholinergic activity of atypical antipsychotic medications.

BACKGROUND: Atypical antipsychotics clozapine, olanzapine, and quetiapine have significant affinity for the muscarinic receptors in vitro, while aripiprazole, risperidone, and ziprasidone do not. Dissimilarity in binding profiles may contribute to the reported differences in the anticholinergic effects of these antipsychotics. However, it is difficult with the available data to predict the likelihood of anticholinergic effects occurring with various doses of an atypical antipsychotic. METHODS: We developed a model to assess the potential anticholinergic activity (AA) of atypical antipsychotics at therapeutic doses. A radioreceptor assay was used to measure in vitro AA at 6 clinically relevant concentrations of aripiprazole, clozapine, olanzapine, quetiapine, risperidone, and ziprasidone. Using published pharmacokinetic data, in combination with the measured in vitro AA, dose-AA curves were generated. RESULTS: Clozapine, and to a lesser extent olanzapine and quetiapine showed dose-dependent increases in AA. At therapeutic doses, the AA (in pmol/mL of atropine equivalents) was estimated to range from 27-250, 1-15, and 0-5.4 pmol/mL for clozapine, olanzapine, and quetiapine, respectively. Aripiprazole, risperidone, and ziprasidone did not demonstrate AA at any of the concentrations studied. CONCLUSIONS: Therapeutic doses of clozapine, olanzapine, and, to a lesser extent, quetiapine are associated with clinically relevant AA.

Adult↗
PubMed2006

Risperidone in the treatment of psychosis of Alzheimer disease: results from a prospective clinical trial.

OBJECTIVE: The objective of this study was to evaluate efficacy and safety of low-dose risperidone for treating psychosis of Alzheimer disease (AD). METHOD: The authors conducted a randomized, eight-week, double-blind, placebo-controlled, multicenter trial involving nursing home residents diagnosed with AD and psychosis. Four hundred seventy-three patients were randomly assigned to placebo (N = 238) or 1.0 to 1.5 mg risperidone per day (N = 235). Coprimary efficacy end points were: changes in scores on the Behavioral pathology in Alzheimer's Disease (BEHAVE-AD) Psychosis subscale and Clinical Global Impression of Change (CGI-C). Protocol-specified subgroup analyses were performed by demographics and dementia severity. RESULTS: Efficacy analysis included 416 patients. Both groups improved significantly on the BEHAVE-AD Psychosis subscale and CGI-C with no significant difference between groups. In the subgroups analyses, a statistically significant treatment by Mini-Mental Status Examination (MMSE) interaction on the CGI-C (F([2,381]) = 3.90, p = 0.021) was observed with patients with more severe dementia (MMSE <10) showing significant differences at end point favoring risperidone treatment (chi(2) ([1]) = 5.11, p = 0.024). Mean risperidone dose was 1.03 +/- 0.24 mg per day. All-cause discontinuation rates were 25% for both risperidone and placebo. Treatment-emergent adverse events occurred in 74% risperidone versus 64% placebo patients, with somnolence occurring significantly more frequently with risperidone (16.2% versus 4.6%). Nine (3.8%) risperidone- and six (2.5%) placebo patients died during or within 30 days after treatment. CONCLUSION: This trial did not confirm earlier findings in this population.

Aged↗
PubMed2004

Smokers and nonsmokers equally affected by olanzapine-induced weight gain: metabolic implications.

OBJECTIVE: To examine the impact of smoking status on antipsychotic-associated weight gain. METHOD: In two double-blind studies, 552 adult and elderly patients with schizophrenia or schizoaffective disorder were randomly assigned to risperidone or olanzapine treatment for 8 weeks. Smoking status at baseline was recorded together with other background characteristics. RESULTS: In both adult and elderly patients, olanzapine-treated smokers and nonsmokers gained weight at a similar rate, whereas risperidone-treated smokers gained less weight than did nonsmokers. Olanzapine was associated with significantly greater weight gain than was risperidone across all measures in both adult and elderly patients. CONCLUSION: These findings support a quantitatively or qualitatively different effect of risperidone and olanzapine on the metabolic changes underlying antipsychotic-associated weight gain. Mechanisms responsible for olanzapine's effect on weight appear to counteract smokers' physiologic bias toward weight loss, an effect not seen among risperidone-treated patients.

Adult↗
PubMed2004

Efficacy and safety of long-acting risperidone in elderly patients with schizophrenia and schizoaffective disorder.

BACKGROUND: Elderly patients are often an underserved population in terms of optimizing treatment outcomes. Long-acting risperidone, the first long-acting injectable atypical antipsychotic, can improve outcomes through continuous medication delivery. OBJECTIVE: To assess the efficacy and safety of long-acting injectable risperidone in elderly patients with psychotic disorders. METHODS: This is a subanalysis of 57 patients aged > or =65 years enrolled in an open-label study of long-acting risperidone that included 725 symptomatically stable patients with schizophrenia or schizoaffective disorder. Patients were assigned to receive 25, 50, or 75 mg of long-acting risperidone every 2 weeks for up to 50 weeks. RESULTS: Fifty-seven elderly patients (mean +/- SE age, 70.9 +/- 0.7 years) were enrolled. Mean Positive and Negative Syndrome Scale (PANSS) total scores improved significantly throughout the study and at endpoint (p < 0.001). The PANSS factor scores (positive symptoms, negative symptoms, disorganized thoughts, uncontrolled hostility/excitement, and anxiety/depression) also significantly improved (p < 0.01). Clinical improvement (> or =20% reduction in PANSS total scores) was achieved by 49% of these stable patients, and 55% improved on the Clinical Global Impressions scale. Severity of movement disorders (Extrapyramidal Symptom Rating Scale scores) was reduced significantly. Adverse events reported in >10% of patients were insomnia (14%), constipation (12%), and bronchitis (12%). CONCLUSIONS: Long-acting risperidone was associated with significant symptom improvements in stable elderly patients with schizophrenia or schizoaffective disorder. Treatment was well tolerated.

Aged↗
PubMed2004

Efficacy and safety of long-acting risperidone in stable patients with schizoaffective disorder.

BACKGROUND: The treatment of schizoaffective disorder is often complicated by the variety of symptoms that contribute to its pathology. Data from a large study (n=725), which included schizoaffective patients to assess the effect of long-acting risperidone, are presented. METHOD: A multicenter, open-label study enrolled non-acute, clinically stable patients with schizoaffective disorder (n=110). Patients on a stable dose of antipsychotic for at least 4 weeks at study entry were switched to long-acting risperidone every 2 weeks for 50 weeks. RESULTS: Mean Positive and Negative Syndrome Scale (PANSS) total scores (+/-S.E.) improved significantly (p<0.001) at each measured time point, including endpoint (-9.0+/-1.6), compared with baseline. Significant reductions were observed on mean PANSS cluster scores for both anxiety/depression (-1.3+/-0.4, p<0.001) and uncontrolled hostility/excitement (-0.7+/-0.3, p<0.05). In addition, scores improved significantly for positive symptoms (-2.2+/-0.5, p<0.001), negative symptoms (-3.1+/-0.5, p<0.001), and disorganized thoughts (-1.7+/-0.4, p<0.001). The overall subjective score of movement disorders was low at baseline (3.6+/-4.1) and had significantly decreased at endpoint (2.75; p<0.05). Patients were previously treated with antipsychotics for 398+/-790 days before being switched to long-acting risperidone. LIMITATIONS: Although this was a 50-week study, which included over 100 patients with schizoaffective disorder, limitations include the open-label design and that it was not designed specifically to assess patients with this disorder. PANSS symptom domains previously defined by factor analytic methods were used for mood symptom measures. No specific mood symptom scales were administered in this study. CONCLUSION: Patients with schizoaffective disorder, considered stable on their antipsychotic medication at study entry, experienced additional significant clinical improvements and minimal side effects with injections of long-acting risperidone over a 50-week study period.

Administration, Oral↗
PubMed2003

Comparative effects of risperidone and olanzapine on cognition in elderly patients with schizophrenia or schizoaffective disorder.

OBJECTIVE: To examine the effects of risperidone and olanzapine on cognitive functioning in elderly patients with schizophrenia or schizoaffective disorder. METHOD: One hundred seventy-six elderly inpatients and outpatients with schizophrenia or schizoaffective disorder were enrolled in this multicenter, double-blind trial. After their antipsychotic medications were tapered for 1 week, patients were randomly assigned to receive either risperidone 1 to 3 mg/day or olanzapine 5 to 20 mg/day for 8 weeks. Performance on the Continuous Performance Test (CPT), Serial Verbal Learning Test (SVLT), TMT (Trail Making Test) Parts A and B, Wisconsin Card Sorting Test (WCST), and Verbal Fluency Examinations (VFE) was assessed at baseline and at end point. RESULTS: Patients in the risperidone group had improved scores on at least one test of attention, memory, executive function, and verbal fluency, and those in the olanzapine group had improved scores on at least one test of attention and memory function. Scores on the TMT Part B, WCST total errors (executive function domain), and the VFE improved significantly from baseline in the risperidone group but not in the olanzapine group. No significant differences in change scores between the two groups were found. Higher baseline scores on each test predicted more improvement at endpoint. CONCLUSIONS: Low doses of risperidone and olanzapine improve cognitive function in elderly patients with schizophrenia or schizoaffective disorder. Consistent with research in younger populations, these improvements occur in aspects of cognitive functioning related to functional outcome.

Aged↗
PubMedDate not supplied

International multisite double-blind trial of the atypical antipsychotics risperidone and olanzapine in 175 elderly patients with chronic schizophrenia.

OBJECTIVE: The authors compared the effects of the two most commonly used atypical antipsychotics, risperidone and olanzapine, in elderly patients with schizophrenia. METHODS: In an 8-week, international, double-blind study, patients (outpatients, hospital inpatients, and residents of nursing or boarding homes) were randomly assigned to receive risperidone (1 mg to 3 mg/day) or olanzapine (5 mg to 20 mg/day). The main outcome measures were changes in Positive and Negative Syndrome Scale (PANSS) total scores and rates of extrapyramidal symptoms (EPS). RESULTS: Subjects were 175 patients age 60 years or over with schizophrenia or schizoaffective disorder. The mean duration of illness was 36.5 years. Median doses were 2 mg/day of risperidone and 10 mg/day of olanzapine. PANSS total scores and four of the five PANSS factor scores (positive symptoms, negative symptoms, disorganized thoughts, and anxiety/depression) improved significantly at all time-points and at endpoint in both groups; between-treatment differences were not significant. EPS-related adverse events were reported by 9.2% of patients in the risperidone group and 15.9% in the olanzapine group; the between-treatment difference was not significant. Total scores on the Extrapyramidal Symptom Rating Scale were reduced in both groups at endpoint; between-treatment differences were not significant. Clinically relevant weight gain was seen in both groups, but was significantly less frequent in risperidone patients than in olanzapine patients. CONCLUSIONS: Stable elderly patients with chronic schizophrenia receiving appropriate doses of risperidone or olanzapine over an 8-week period experienced significant reductions in the severity of psychotic and extrapyramidal symptoms, with a relatively low risk of side effects.

Aged↗