Search PubMed⌕ Search

Biomedical subjects

Guy Chouinard

Publications and source records attributed to Guy Chouinard.

30 records · Page 2Linked to original sources
PubMed2004

New nomenclature for drug-induced movement disorders including tardive dyskinesia.

Psychotropic agents are increasingly being prescribed by different specialty clinicians for a variety of psychiatric illnesses, making it necessary to improve understanding of the etiology, diagnosis, and management of drug-induced movement disorders (D-IMD) across medical specialties. Early descriptions of movement disorders were based on identifiable disease states such as parkinsonism, dystonia deformans, and Huntington's chorea, which introduced complicated and often overlapping nomenclature. This has hindered communication about, description of, and diagnosis of these drug-induced disorders. Research criteria for tardive dyskinesia, a specific, purposeless, involuntary, hyperkinetic, potentially persistent D-IMD, have varied, with relatively few data-driven conclusions available to support clinical decision-making. The differences in research criteria among published reports on rates of tardive dyskinesia with atypical antipsychotics make it difficult to find meaningful comparisons and conclusions between atypicals. A novel system for classifying D-IMD according to whether they are reversible or persistent, hypokinetic or hyperkinetic, and dystonic or nondystonic is proposed. This new classification system will provide clinicians and researchers across specialties a more precise language, which will hopefully improve the diagnosis of and research criteria for D-IMD.

Adult↗
PubMed2003

Clozapine treatment for suicidality in schizophrenia: International Suicide Prevention Trial (InterSePT).

BACKGROUND: Approximately 50% of patients with schizophrenia or schizoaffective disorder attempt suicide, and approximately 10% die of suicide. Study results suggest that clozapine therapy significantly reduces suicidal behavior in these patients. METHODS: A multicenter, randomized, international, 2-year study comparing the risk for suicidal behavior in patients treated with clozapine vs olanzapine was conducted in 980 patients with schizophrenia or schizoaffective disorder, 26.8% of whom were refractory to previous treatment, who were considered at high risk for suicide because of previous suicide attempts or current suicidal ideation. To equalize clinical contact across treatments, all patients were seen weekly for 6 months and then biweekly for 18 months. Subsequent to randomization, unmasked clinicians at each site could make any interventions necessary to prevent the occurrence of suicide attempts. Suicidal behavior was assessed at each visit. Primary end points included suicide attempts (including those that led to death), hospitalizations to prevent suicide, and a rating of "much worsening of suicidality" from baseline. Masked raters, including an independent suicide monitoring board, determined when end point criteria were achieved. RESULTS: Suicidal behavior was significantly less in patients treated with clozapine vs olanzapine (hazard ratio, 0.76; 95% confidence interval, 0.58-0.97; P =.03). Fewer clozapine-treated patients attempted suicide (34 vs 55; P =.03), required hospitalizations (82 vs 107; P =.05) or rescue interventions (118 vs 155; P =.01) to prevent suicide, or required concomitant treatment with antidepressants (221 vs 258; P =.01) or anxiolytics or soporifics (301 vs 331; P =.03). Overall, few of these high-risk patients died of suicide during the study (5 clozapine vs 3 olanzapine-treated patients; P =.73). CONCLUSIONS: Clozapine therapy demonstrated superiority to olanzapine therapy in preventing suicide attempts in patients with schizophrenia and schizoaffective disorder at high risk for suicide. Use of clozapine in this population should lead to a significant reduction in suicidal behavior.

Adolescent↗
PubMed2003

Intramuscular olanzapine and intramuscular haloperidol in acute schizophrenia: antipsychotic efficacy and extrapyramidal safety during the first 24 hours of treatment.

OBJECTIVE: To determine the antipsychotic efficacy and extrapyramidal safety of intramuscular (i.m.) olanzapine and i.m. haloperidol during the first 24 hours of treatment of acute schizophrenia. METHOD: Patients (n = 311) with acute schizophrenia were randomly allocated (2:2:1) to receive i.m. olanzapine (10.0 mg, n = 131), i.m. haloperidol (7.5 mg, n = 126), or i.m. placebo (n = 54). RESULTS: After the first injection, i.m. olanzapine was comparable to i.m. haloperidol and superior to i.m. placebo for reducing mean change scores from baseline on the Brief Psychiatric Rating Scale (BRPS) Positive at 2 hours (-2.9 olanzapine, -2.7 haloperidol, and -1.5 placebo) and 24 hours (-2.8 olanzapine, -3.2 haloperidol, and -1.3 placebo); the BPRS Total at 2 hours (-14.2 olanzapine,-13.1 haloperidol, and -7.1 placebo) and 24 hours (-12.8 olanzapine, -12.9 haloperidol, and -6.2 placebo); and the Clinical Global Impressions (CGI) scale at 24 hours (-0.5 olanzapine, -0.5 haloperidol, and -0.1 placebo). Patients treated with i.m. olanzapine had significantly fewer incidences of treatment-emergent parkinsonism (4.3% olanzapine vs 13.3% haloperidol, P = 0.036), but not akathisia (1.1% olanzapine vs 6.5% haloperidol, P = 0.065), than did patients treated with i.m. haloperidol; they also required significantly less anticholinergic treatment (4.6% olanzapine vs 20.6% haloperidol, P < 0.001). Mean extrapyramidal symptoms (EPS) safety scores improved significantly from baseline during i.m. olanzapine treatment, compared with a general worsening during i.m. haloperidol treatment (Simpson-Angus Scale total score mean change: -0.61 olanzapine vs 0.70 haloperidol; P < 0.001; Barnes Akathisia Scale global score mean change: -0.27 olanzapine vs 0.01 haloperidol; P < 0.05). CONCLUSION: I.m. olanzapine was comparable to i.m. haloperidol for reducing the symptoms of acute schizophrenia during the first 24 hours of treatment, the efficacy of both being evident within 2 hours after the first injection. In general, more EPS were observed during treatment with i.m. haloperidol than with i.m. olanzapine.

Acute Disease↗
PubMed2002

Risperidone in the treatment of tourette syndrome: a double-blind, placebo-controlled trial.

A double-blind, placebo-controlled trial was performed to determine the efficacy and tolerability of 8 weeks of treatment with risperidone in the management of 48 adolescent and adult patients with Tourette syndrome. Twenty-four patients were randomly assigned to treatment with risperidone in doses of 0.5 to 6.0 mg/day, and 24 were assigned to placebo. The dosage of medication was increased in fixed increments during the first week of double-blind treatment and thereafter in a flexible dose regimen according to clinical response. Risperidone, at a median dose of 2.5 mg/day (range, 1 to 6 mg/day), was found to be significantly ( p < 0.05) superior to placebo on the Global Severity Rating of the Tourette Syndrome Severity Scale. The proportion of patients who improved by at least one point on this seven-point scale was 60.8% in the risperidone group and 26.1% in the placebo group. Treatment with risperidone was accompanied by an improvement in global functioning in patients with average to above-average impairment at baseline as measured by the Global Assessment of Functioning scale. With respect to extrapyramidal symptom scores measured on the Extrapyramidal Symptom Rating Scale, hypokinesia and tremor increased in the risperidone group, but the effect on tremor was largely confined to subjects with higher baseline tremor scores. There were no significant differences in dystonic reactions, dyskinetic movements, subjective parkinsonism, or akathisia. Risperidone did not increase obsessive-compulsive symptoms. Fatigue and somnolence were the most common adverse events associated with risperidone.

Adolescent↗
PubMed2002

Therapeutic tolerance and rebound psychosis during quetiapine maintenance monotherapy in patients with schizophrenia and schizoaffective disorder.

A 3-year open-label study was conducted to determine the long-term safety and efficacy of quetiapine monotherapy in schizophrenia and schizoaffective disorder.Twenty-three male outpatients previously stable but with inter-episode residual symptoms on classical antipsychotics and/or risperidone and who had complained of side effects were selected. To initiate quetiapine, patients were hospitalized for 13 days and then treated as outpatients. Quetiapine dosage was adjusted according to therapeutic effects. Only five patients (21.7%) completed 77 to 96 weeks of the study. Initial dose was 261 +/- 65.6 mg/day (mean +/- S.D.) administered in divided doses, with an ending dose of 487 +/- 209.6 mg/day, corresponding with an 86.6% dose increase over the course of the study. For those completing 12 weeks or less (n = 11), mean ending dose was 362 +/- 184.8 mg/day a 38.7% dose increase over baseline. For those completing 25 weeks or more (n = 12), mean ending dose was 592 +/- 178.2 mg/day, a 126.8% dose increase over baseline. Six of the seven patients who relapsed after being stabilized on quetiapine for at least three months met criteria for supersensitivity psychosis (SSP).Therapeutic tolerance and rebound psychosis were found to develop with quetiapine in male patients with a history of chronic treatment with classical antipsychotics. Seeman and Tallerico3 have proposed pharmacologic explanations for quetiapine and clozapine drug-induced rebound phenomena.

Adult↗