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Biomedical subjects

A Breier

Publications and source records attributed to A Breier.

At least 37 records · Page 2Linked to original sources
PubMed2001

A current review of olanzapine's safety in the geriatric patient: from pre-clinical pharmacology to clinical data.

OBJECTIVE: Olanzapine (OLZ) is unique among currently available antipsychotic medications in its antagonism of a range of receptor systems including dopamine, norepinephrine, serotonin, acetylcholine, and histamine. Olanzapine's mechanistic complexity provides a broad efficacy profile in patients with schizophrenia and acute, pure or mixed mania. Patients experience symptomatic relief of mania, anxiety, hallucinations, delusions, and agitation/aggression and reduced depressive, negative, and some cognitive symptoms. This paper will review the safety profile of OLZ, focusing on the elderly, where data are available. METHOD: Preclinical and clinical studies of OLZ are reviewed, with emphasis on its possible effects on the cholinergic system and the histamine H(1) receptor. Weight change and related metabolic considerations, cardiac and cardiovascular safety, and motor function during treatment with OLZ are also reviewed. RESULTS AND CONCLUSION: In vitro receptor characterization methods, when done using physiologically relevant conditions allow accurate prediction of the relatively low rate of anticholinergic-like adverse events, extrapyramidal symptoms, and cardiovascular adverse events during treatment with OLZ. Currently available clinical data suggest olanzapine is predictably safe in treating adult patients of any age with schizophrenia and acute bipolar mania, as well as in treatment of patients with some types of neurodegenerative disorders.

Adverse Drug Reaction Reporting Systems↗
PubMed2001

Olanzapine versus haloperidol in schizoaffective disorder, bipolar type.

BACKGROUND: The present analysis was performed on data from a subsample of patients with schizoaffective disorder, bipolar type, who participated in a multicenter, double-blind study comparing olanzapine to haloperidol. METHODS: Patients with schizoaffective disorder bipolar type, characterized as currently manic, mixed, depressed, or euthymic, were assessed weekly for 6 weeks during treatment with either olanzapine or haloperidol. Manic symptoms were measured using the sum of six items of the BPRS, and depressive symptoms were assessed using the Montgomery-Asberg Depression Rating Scale. In addition, cognitive functioning was measured using the sum of seven items from the PANSS. Repeated measures analyses were performed using random coefficients regression of the serial measurement of manic, cognitive, and depressive symptoms. RESULTS: A significant treatment difference was detected overall, indicating that olanzapine was significantly more effective than haloperidol in reducing symptoms of depression and improving patients' cognitive symptoms. The superiority of olanzapine over haloperidol in the reduction of manic symptoms did not reach statistical significance (P=.052). The greatest improvement in both manic and cognitive symptoms was seen in the olanzapine-treated 'currently manic' subgroup, and least improvement in the haloperidol-treated 'euthymic' subgroup. Depressive symptoms were most improved in the olanzapine-treated 'depressed' subgroup, and least improved in the corresponding haloperidol subgroup. CONCLUSIONS: Overall, olanzapine was superior to haloperidol with respect to thymoleptic effects in patients with schizoaffective disorder, bipolar type.

Administration, Oral↗
PubMed2001

SB203580, a specific inhibitor of p38-MAPK pathway, is a new reversal agent of P-glycoprotein-mediated multidrug resistance.

P-glycoprotein (P-gp) is the plasma membrane transport pump responsible for efflux of chemotherapeutic agents from cells and is one of the systems that secures multidrug resistance (MDR) of neoplastic cells. In the present study, drug sensitive L1210 and multidrug resistant L1210/VCR (characterized by overexpression of P-gp) mouse leukemic cell lines were used as an experimental model. We have found that SB203580, a specific inhibitor of p38-MAPK pathway, significantly reduced the degree of the vincristine resistance in L1210/VCR cells. This phenomenon was accompanied by a decrease in the LC(50) value of vincristine from 3.203+/-0.521 to 0.557+/-0.082 microM. The LC(50) value of sensitive cells for vincristine was about 0.011 microM. The effect of SB203580 on L1210/VCR cells was associated with significantly increased intracellular accumulation of [3H]-vincristine in the concentration dependent manner. Prolonged exposure of resistant cells to 30 microM SB203580 did neither significantly influence the gene expression of P-gp, nor change the protein levels of p38-MAPK. Western blot analysis revealed that the MDR phenotype in L1210/VCR cells was associated with increased level and activity of cytosolic p38-MAPK. In resistant cells, the enhanced phosphorylation of both, p38-MAPK and ATF-2 (endogenous substrate for p38-MAPK) was found as well. In conclusion we could remark that SB203580, an inhibitor of p38 kinase pathway, reversed the MDR resistance of L1210/VCR cells. MDR phenotype of these cells is connected with increased levels and activities of p38-MAPK. These findings point to the possible involvement of the p38-MAPK pathway in the modulation of P-gp mediated multidrug resistance in the L1210/VCR mouse leukemic cell line. However, the mechanisms of SB203580 action should be further investigated.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2001

A double-blind, randomized comparison of the efficacy and safety of intramuscular injections of olanzapine, lorazepam, or placebo in treating acutely agitated patients diagnosed with bipolar mania.

There are no rapid-acting intramuscular formulations of atypical antipsychotics available for quickly calming an agitated patient with bipolar disorder. In this study, 201 agitated patients with bipolar mania were randomly assigned to receive one to three injections of the atypical antipsychotic olanzapine (10 mg, first two injections; 5 mg, third injection), the benzodiazepine lorazepam (2 mg, first two injections; 1 mg, third injection), or placebo (placebo, first two injections; olanzapine, 10 mg, third injection) within a 24-hour period. Agitation was measured at baseline, every 30 minutes for the first 2 hours, and at 24 hours after the first injection using the Positive and Negative Syndrome Scale-Excited Component subscale and two additional agitation scales. At 2 hours after the first injection, patients treated with olanzapine showed a significantly greater reduction in scores on all agitation scales compared with patients treated with either placebo or lorazepam. At 24 hours after the first injection, olanzapine remained statistically superior to placebo in reducing agitation in patients with acute mania, whereas patients treated with lorazepam were not significantly different from those treated with placebo or olanzapine. Furthermore, no significant differences among the three treatment groups were observed in safety measures, including treatment-emergent extrapyramidal symptoms, the incidence of acute dystonia, or QTc interval changes. These findings suggest that intramuscular olanzapine is a safe and effective treatment for reducing acute agitation in patients with bipolar mania.

Adult↗
PubMed2001

Double-blind, placebo-controlled comparison of intramuscular olanzapine and intramuscular haloperidol in the treatment of acute agitation in schizophrenia.

OBJECTIVE: The authors evaluated the comparative efficacy and safety of intramuscular olanzapine, intramuscular haloperidol, and intramuscular placebo for the treatment of acute agitation in schizophrenia. METHOD: Hospitalized patients with schizophrenia received one to three injections of intramuscular olanzapine, 10 mg, intramuscular haloperidol, 7.5 mg, or intramuscular placebo over a 24-hour period. Agitation was measured with the excited component of the Positive and Negative Syndrome Scale and two additional scales. RESULTS: According to scores on the excited component of the Positive and Negative Syndrome Scale, both intramuscular olanzapine and intramuscular haloperidol reduced agitation significantly more than intramuscular placebo 2 and 24 hours following the first injection. Intramuscular olanzapine reduced agitation significantly more than intramuscular haloperidol 15, 30, and 45 minutes following the first injection. No patients treated with intramuscular olanzapine experienced acute dystonia, compared with 7% of those who were treated with intramuscular haloperidol. No significant QT(c) interval changes were observed in any patients. CONCLUSIONS: Intramuscular olanzapine represents a rapid, effective, and safe treatment for acute agitation in schizophrenia.

Acute Disease↗
PubMed2001

The effects of olanzapine in reducing the emergence of psychosis among nursing home patients with Alzheimer's disease.

BACKGROUND: Elderly patients with Alzheimer's disease (AD) commonly exhibit psychotic symptoms, prompting clinicians to administer antipsychotics. This article compares the effects of olanzapine and placebo in the emergence of hallucinations or delusions in AD patients with symptoms of agitation/aggression but little or no psychotic symptomatology at baseline. METHOD: A multicenter, double-blind, placebo-controlled study was conducted in nursing home patients with AD according to DSM-IV criteria and symptoms of agitation/aggression and/or psychosis. Patients (N = 206) were randomly assigned to receive either placebo or fixed-dose olanzapine (5, 10, or 15 mg/day) for up to 6 weeks. This article analyzes data from a subgroup of patients (N = 165) with no or minimal delusions and/or hallucinations at baseline as measured by the Neuropsychiatric Inventory-Nursing Home Version (NPI/NH). Three subsets of patients were identified on the basis of their symptoms at baseline: those with no clinically significant hallucinations, those with no clinically significant delusions, and those with no clinically significant delusions or hallucinations. RESULTS: Of the patients without hallucinations or delusions at baseline (N = 75), the placebo-treated patients showed significantly greater development of these symptoms compared with olanzapine-treated patients overall (NPI/NH hallucinations + delusions mean change score, +2.73 vs. +0.27, p = .006). Similarly, of the patients without baseline hallucinations (N = 153), the placebo-treated patients showed greater hallucinations score increases than did olanzapine-treated patients overall (+1.25 vs. +0.33, p = .026), whereas patients without baseline delusions (N = 87) showed no significant treatment effects. Olanzapine had a favorable safety profile in each patient subset. CONCLUSION: These results suggest that, overall, olanzapine effectively attenuated emergence of psychosis in a short-term trial of patients with Alzheimer's disease.

Aged↗
PubMed2001

Drug transporters and their role in multidrug resistance of neoplastic cells.

Multidrug resistance (MDR) of neoplastic cells, i.e. resistance towards large groups of unrelated drugs, represents the phenomenon that dramatically depresses the effectiveness of cancer chemotherapy. Membrane transport of ATPases from ABC superfamily plays an important role in MDR. In the present paper we are aiming to compare two members of this family: P-glycoprotein (PGP products of mdr genes) and multidrug resistance-associated protein (MRP, products of mrp genes) and their impact for MDR of neoplastic cells.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2001

Reversal effect of specific inhibitors of extracellular-signal regulated protein kinase pathway on P-glycoprotein mediated vincristine resistance of L1210 cells.

Effect of specific inhibitors of extracellular-signal regulated protein kinase (ERK) pathway, PD98059 and U0126, on P-glycoprotein (Pgp)-mediated vincristine resistance of L1210/VCR cells was investigated. Both test inhibitors significantly reduced the survival of L1210/VCR cells in the presence of vincristine and this was associated with a decrease of LC50 values to vincristine from 2.65+/-0.43 to 0.67+/-0.28 micromol/l and to 0.69+/-0.09 micromol/l after treatment with 50 micromol/l PD98059 and 25 micromol/l UO126, respectively. Moreover, the effects of PD98059 are connected also with an increased intracellular accumulation of radiolabeled vincristine in resistant L1210/VCR cells in concentration dependent manner. The results of this study demonstrate that inhibitors of ERK signaling pathway are reversal agents of vincristine resistance in L1210/VCR cells. The precise mechanism of PD98059 and U0126 action in modulation of MDR is not resolved yet, but the role of ERK-mediated phosphorylation cascade could be considered.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2000

Olanzapine treatment of psychotic and behavioral symptoms in patients with Alzheimer disease in nursing care facilities: a double-blind, randomized, placebo-controlled trial. The HGEU Study Group.

BACKGROUND: Patients with Alzheimer disease (AD) commonly exhibit psychosis and behavioral disturbances that impair patient functioning, create caregiver distress, and lead to institutionalization. This study was conducted to assess the efficacy and safety of olanzapine in treating psychosis and/or agitation/aggression in patients with AD. METHODS: A multicenter, double-blind, placebo-controlled, 6-week study was conducted in 206 elderly US nursing home residents with AD who exhibited psychotic and/or behavioral symptoms. Patients were randomly assigned to placebo or a fixed dose of 5, 10, or 15 mg/d of olanzapine. The primary efficacy measure was the sum of the Agitation/Aggression, Hallucinations, and Delusions items (Core Total) of the Neuropsychiatric Inventory-Nursing Home version. RESULTS: Low-dose olanzapine (5 and 10 mg/d) produced significant improvement compared with placebo on the Core Total (-7.6 vs -3.7 [P<.001] and -6.1 vs -3. 7 [P =.006], respectively). Core Total improvement with olanzapine, 15 mg/d, was not significantly greater than placebo. The Occupational Disruptiveness score, reflecting the impact of patients' psychosis and behavioral disturbances on the caregiver, was significantly reduced in the 5-mg/d olanzapine group compared with placebo (-2.7 vs -1.5; P =.008). Somnolence was significantly more common among patients receiving olanzapine (25.0%-35.8%), and gait disturbance occurred in those receiving 5 or 15 mg/d (19.6% and 17.0%, respectively). No significant cognitive impairment, increase in extrapyramidal symptoms, or central anticholinergic effects were found at any olanzapine dose relative to placebo. CONCLUSION: Low-dose olanzapine (5 and 10 mg/d) was significantly superior to placebo and well tolerated in treating agitation/aggression and psychosis in this population of patients with AD.

Aged↗
PubMed2000

Neuropsychological change in early phase schizophrenia during 12 months of treatment with olanzapine, risperidone, or haloperidol. The Canadian Collaborative Group for research in schizophrenia.

BACKGROUND: The purpose of this investigation was to test the efficacy of novel antipsychotic medications in the treatment of cognitive impairment in early phase schizophrenia. METHODS: Sixty-five patients in this multicenter double-blind study were randomly assigned to olanzapine (5-20 mg), risperidone (4-10 mg), or haloperidol (5-20 mg). Standard measures of clinical and motor syndromes were administered, as well as a comprehensive battery of tests to assess (1) motor skills, (2) attention span, (3) verbal fluency and reasoning, (4) nonverbal fluency and construction, (5) executive skills, and (6) immediate recall at baseline and after 6, 30, and 54 weeks of treatment. RESULTS: The general cognitive index derived from the 6 domain scores revealed a significantly greater benefit from treatment with olanzapine relative to haloperidol and olanzapine relative to risperidone, but no significant difference was shown between risperidone and haloperidol. The improvement related to olanzapine was apparent after 6 weeks and enhanced after 30 and 54 weeks of treatment. Exploratory within-group analyses of the 6 cognitive domains after a conservative Bonferroni adjustment revealed a significant improvement with olanzapine only on the immediate recall domain, and similar analyses of the 17 individual tests revealed a significant improvement with olanzapine only on the Hooper Visual Organization Test. CONCLUSIONS: These data suggest that olanzapine has some superior cognitive benefits relative to haloperidol and risperidone. A larger sample replication study is necessary to confirm and generalize the observations of this study and begin evaluation of the implications of this change to cerebral function and quality of life for people with schizophrenia.

Adolescent↗
PubMed2000

Efficacy of olanzapine in acute bipolar mania: a double-blind, placebo-controlled study. The Olanzipine HGGW Study Group.

BACKGROUND: We compared the efficacy and safety of olanzapine vs placebo for the treatment of acute bipolar mania. METHODS: Four-week, randomized, double-blind, parallel study. A total of 115 patients with a DSM-IV diagnosis of bipolar disorder, manic or mixed, were randomized to olanzapine, 5 to 20 mg/d (n = 55), or placebo (n = 60). The primary efficacy measure was the Young-Mania Rating Scale (Y-MRS) total score. Response and euthymia were defined, a priori, as at least a 50% improvement from baseline to end point and as a score of no less than 12 at end point in the Y-MRS total score, respectively. Safety was assessed using adverse events, Extrapyramidal Symptom (EPS) rating scales, laboratory values, electrocardiograms, vital signs, and weight change. RESULTS: Olanzapine-treated patients demonstrated a statistically significant greater mean (+/- SD) improvement in Y-MRS total score than placebo-treated patients (-14.8 +/- 12.5 and -8.1 +/- 12.7, respectively; P<.001), which was evident at the first postbaseline observation 1 week after randomization and was maintained throughout the study (last observation carried forward). Olanzapine-treated patients demonstrated a higher rate of response (65% vs 43%, respectively; P =.02) and euthymia (61% vs 36%, respectively; P =. 01) than placebo-treated patients. There were no statistically significant differences in EPSs between groups. However, olanzapine-treated patients had a statistically significant greater mean (+/- SD) weight gain than placebo-treated patients (2.1 +/- 2.8 vs 0.45 +/- 2.3 kg, respectively) and also experienced more treatment-emergent somnolence (21 patients [38.2%] vs 5 [8.3% ], respectively). CONCLUSION: Olanzapine demonstrated greater efficacy than placebo in the treatment of acute bipolar mania and was generally well tolerated.

Acute Disease↗
PubMed2000

The effects of olanzapine, risperidone, and haloperidol on plasma prolactin levels in patients with schizophrenia.

BACKGROUND: There is relatively little comparative information on elevations in plasma prolactin level (PRL) with conventional versus novel antipsychotic agents. OBJECTIVE: This paper examines the comparative effects on PRL of olanzapine, risperidone, and haloperidol based on data from 3 multicenter, double-blind, randomized clinical trials. Magnitude of response, dose dependency, time course, effects of sex and age, and response to switching from haloperidol to olanzapine are assessed. METHODS: The effects of olanzapine, risperidone, and haloperidol on PRL were assessed in patients with schizophrenia or related psychoses participating in 3 double-blind clinical trials: (1) a 6-week acute trial comparing olanzapine 5 to 20 mg/d (n = 1,336) and haloperidol 5 to 20 mg/d (n = 660), with a 1-year, open-label olanzapine extension for responders; (2) a 54-week study comparing olanzapine 5 to 20 mg/d (n = 21), risperidone 4 to 10 mg/d (n = 21), and haloperidol 5 to 20 mg/d (n = 23) in early illness; and (3) a 28-week study comparing olanzapine 10 to 20 mg/d (n = 172) and risperidone 4 to 12 mg/d (n = 167). RESULTS: PRL elevations were significantly greater with risperidone than with either olanzapine or haloperidol in study 2. and significantly greater than with olanzapine in study 3 (all, P < 0.001). PRL elevations were significantly greater with haloperidol than with olanzapine in study 1 (P < 0.001 ). A dose-response relationship was not consistently confirmed with any of the drug treatments. Risperidone-associated PRL elevations peaked relatively early in treatment. In haloperidol- and risperidone-treated patients, the mean change in PRL was greater in women than in men. PRL decreased significantly when treatment was switched from haloperidol to olanzapine. CONCLUSIONS: This side-by-side analysis of 3 independent studies suggests that with the 3 antipsychotic drugs studied, PRL is elevated moderately by olanzapine (mean change, 1-4 ng/mL), intermediately by haloperidol (mean change, approximately 17 ng/mL), and strongly by risperidone (mean change, 45-80 ng/mL). No consistent dose-response relationship was observed, and the time course and sex-dependency of the response differed between the 3 agents. Patients with haloperidol-induced hyperprolactinemia may benefit from a switch to olanzapine. Long-term studies examining the health consequences of chronic hyperprolactinemia during antipsychotic treatment are needed.

Antipsychotic Agents↗
PubMed2000

Mazindol treatment of negative symptoms.

Hypodopaminergic and hyponoradrenergic pathophysiology may be a basis for primary and/or secondary negative symptoms in schizophrenia. The hypothesis that enhanced neurotransmission in these systems would be therapeutic for negative symptoms was tested by comparing mazindol and placebo in a double-blind, cross-over design trial. Outcome following mazindol supplementation was comparable to placebo supplementation (F(1,30) = 0.9; p = .57). Results for deficit and non-deficit schizophrenia subjects were similar, and were not affected by whether concurrent the antipsychotic drug treatment was clozapine, fluphenazine, or haloperidol. The efficacy hypothesis was not supported for either primary or secondary negative symptoms.

Adult↗
PubMed2000

The relationship between dorsolateral prefrontal neuronal N-acetylaspartate and evoked release of striatal dopamine in schizophrenia.

Schizophrenia has been linked to abnormal dopamine function, recently to excessive amphetamine-induced release of striatal dopamine, and also to pathology of prefrontal cortical neurons. It has been hypothesized that prefrontal pathology is a primary condition that leads to dopamine dysregulation. We evaluated in vivo the relationship between neuronal integrity in dorsolateral prefrontal cortex, assessed as N-acetylaspartate (NAA) relative concentrations measured with proton magnetic resonance spectroscopic imaging, and amphetamine-induced release of striatal dopamine, assessed with 11C-raclopride Positron Emission Tomography (PET) in patients with schizophrenia and in healthy subjects. In the patients, NAA measures in dorsolateral prefrontal cortex selectively predicted striatal displacement of 11C-raclopride after amphetamine infusions (rho = -0.76, p < .02). In contrast, NAA measures in other cortical regions and in healthy subjects did not show any correlation. These results support the hypothesis that in schizophrenia neuronal pathology of dorsolateral prefrontal cortex is directly related to abnormal subcortical dopamine function.

Adult↗
PubMed2000

Effects of acute metabolic stress on striatal dopamine release in healthy volunteers.

Several lines of evidence indicate that a variety of metabolic stressors, including acute glucose deprivation are associated with dopamine release. Pharmacologic doses of the glucose analogue, 2-deoxyglucose (2DG) cause acute glucoprivation and are associated with enhanced dopamine turnover in preclinical studies. In this study, we utilized [11C]raclopride PET to examine 2DG-induced striatal dopamine release in healthy volunteers. Six healthy volunteers underwent PET scans involving assessment of 2DG-induced (40 mg/kg) decrements in striatal binding of the D(2)/D(3) receptor radioligand [11C]raclopride. Decreases in [11C]raclopride specific binding reflect 2DG-induced changes in synaptic dopamine. Specific binding significantly decreased following 2DG administration, reflecting enhanced synaptic dopamine concentrations (p =.02). The administration of 2DG is associated with significant striatal dopamine release in healthy volunteers. Implications of these data for investigations of the role of stress in psychiatric disorders are discussed.

Adult↗
PubMed2000

Functional outcomes in schizophrenia: a comparison of olanzapine and haloperidol in a European sample.

The primary aim of this study was to compare functional outcomes between patients with schizophrenia treated with olanzapine or haloperidol in Europe. The sample consisted of European patients from a large, international, double-blind, randomized clinical trial. Patients were randomized to receive either olanzapine (n = 520) or haloperidol (n = 258) for a 6-week acute phase followed by a 46-week maintenance phase for responders. Olanzapine-treated patients experienced superior improvements compared to haloperidol-treated patients on all efficacy measures assessed in both phases. A greater percentage of olanzapine-treated patients had > or = 20% improvement in the Quality of Life Scale total score during both the acute (50.0% versus 31.0%, P = 0.071) and maintenance (69.5% versus 41.7%, P = 0.006) phases compared to haloperidol-treated patients. For patients who entered the maintenance phase as outpatients, olanzapine-treated patients were significantly less likely to require subsequent hospitalization compared to haloperidol-treated patients (P = 0.001). A significantly greater percentage of the olanzapine group compared to the haloperidol group worked part-time or full-time (15.1% versus 5.3%, P = 0.018), participated in useful work > or = 75% of the time (21.0% versus 10.5%, P = 0.038), and socialized more than once a month (53.8% versus 37.9%, P = 0.004) during the maintenance phase. The findings from this study suggest that olanzapine's clinical profile leads to reduced hospitalization and improvements in work and social functioning superior to that achieved with haloperidol treatment.

Activities of Daily Living↗