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Dive into the research topics where George M. Simpson is active.

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Featured researches published by George M. Simpson.


Biological Psychiatry | 1994

Polydipsia and water intoxication in psychiatric patients: a review of the epidemiological literature.

Jose de Leon; Cherian Verghese; Joseph I. Tracy; Richard C. Josiassen; George M. Simpson

Polydipsia among chronic psychiatric patients is poorly understood and underdiagnosed. It may have three stages: simple polydipsia, polydipsia with water intoxication, and physical complications. Epidemiological surveys have used staff reports and polyuria measures to identify polydipsic patients. Water intoxication has been screened by chart review, weight, or serum sodium data. According to these surveys, polydipsia, not explained by medically induced polyuria, may be present in more than 20% of chronic inpatients. Up to 5% of chronic inpatients had episodes of water intoxication although mild cases may have been missed. Single time point surveys show that 29% of polydipsic patients had presented water intoxication. Methodologically limited clinical studies suggest that polydipsia with water intoxication rather than simple polydipsia may be associated with poor prognosis in schizophrenia. Epidemiological surveys found polydipsia with water intoxication to be associated with chronicity, schizophrenia, smoking, some medications, male gender, and white race. New pathophysiological models need to elucidate these findings.


Progress in Neuro-psychopharmacology & Biological Psychiatry | 2011

A double-blind study of paliperidone palmitate and risperidone long-acting injectable in adults with schizophrenia.

Gahan Pandina; Rosanne Lane; Srihari Gopal; Cristiana Gassmann-Mayer; David Hough; Bart Remmerie; George M. Simpson

This 13-week double-blind study was designed to assess noninferiority of the recently approved (in the U.S.) injectable atypical antipsychotic paliperidone palmitate (PP) versus risperidone long-acting injectable (RIS-LAI) in adult patients with schizophrenia. Patients (N=1220) were randomized (1:1) to either a) PP: deltoid injections on day 1 (150 mg eq.), day 8 (100 mg eq.), and once-monthly flexible dosing as deltoid or gluteal injections on day 36 (50 mg eq. or 100 mg eq.) and day 64 (50 mg eq. or 100 mg eq. or 150 mg eq.) or b) RIS-LAI: gluteal injections days 8 and 22 (25mg), days 36, 50 (25 or 37.5mg) and days 64, 78 (25, 37.5 or 50mg). RIS-LAI-treated patients received oral supplementation with RIS 1-6 mg/day (days 1 to 28), and PP-treated patients received oral placebo. The safety analysis set (n=1214) included 58% men, 78% white, with mean (SD) baseline PANSS total score: PP, 84.1 (12.09); and RIS-LAI, 83.6 (11.28). Mean (SD) change from baseline to endpoint in PANSS total score decreased similarly in both groups; PP (-18.6 [15.45]) and RIS-LAI (-17.9 [14.24]). PP treatment was noninferior to RIS-LAI (point estimate [95% CI]: 0.4 [-1.62;2.38], per-protocol analysis set [primary analysis]). The tolerability and safety of PP was generally similar to RIS-LAI with no new safety or tolerability findings.


Journal of Clinical Psychopharmacology | 2003

Improvement in indices of health status in outpatients with schizophrenia switched to ziprasidone.

Peter J. Weiden; David G. Daniel; George M. Simpson; Steven J. Romano

Side effect and health status changes were measured in 3 studies in which outpatients experiencing suboptimal efficacy or tolerability with their current antipsychotic were switched to 6 weeks of open-label ziprasidone. The studies differed only in the patient’s prior antipsychotic; 1 study group was on olanzapine (n = 104), a second on risperidone (n = 58), and third on a conventional antipsychotic (n = 108). Baseline and end point health status measures included weight and height, nonfasting cholesterol, and triglyceride levels, prolactin levels, and extrapyramidal side effects. Improvements in health indices and side effects were seen among all 3 groups, but the specific benefits depended on the preswitch antipsychotic. For example, patients switched from olanzapine experienced a mean weight loss of 1.76 kg (P < 0.0001), those switched from risperidone had a lesser reduction in weight (−0.86 kg; P = 0.015), and those switched from conventionals had a nonsignificant increase (+0.27 kg; P = 0.3). Prolactin levels decreased among those switched from risperidone (P < 0.0001) or conventionals (P = 0.05), but not for patients switched from olanzapine. EPS improved among those switched from conventionals (P < 0.0001) and to a lesser extent among those switched from risperidone (P < 0.01), but not in those changed from olanzapine (NS). Thus, in these studies, switching to ziprasidone in patients with continuing symptoms or side effects on their current medication was often associated with improved health status indices, lowered prolactin levels, or less EPS, with the magnitude benefit consistent with the known side-effect profile of the preswitch antipsychotic.


Psychopharmacology | 1978

Clozapine in tardive dyskinesia

George M. Simpson; J. Hillary Lee; Ram K. Shrivastava

Clozapine, which has had limited clinical testing in the U.S.A., was evaluated in 12 chronic schizophrenic patients with tardive dyskinesia. Its antipsychotic activity was again demonstrated and it suppressed the symptoms of tardive dyskinesia with a marked rebound occurring in these symptoms when it was withdrawn; there was no rigidity or other Parkinsonian symptoms. However, out of a total of 12 patients, neutropenia (800 and 1120) occurred in two patients, convulsions in one patient, marked withdrawal effects in three patients, and a hypotensive collapse with atrial fibrillation in one patient. If these adverse effects are confirmed in a larger sample size, then despite the novel desirable effects of clozapine it would seem unlikely that it will gain widespread or routine use1.


Journal of Clinical Psychopharmacology | 1997

Extrapyramidal Symptoms in Patients Treated With Risperidone

George M. Simpson; Jean-Pierre Lindenmayer

Data on extrapyramidal symptoms (EPS) from both arms of the North American multicenter comparative study of risperidone, placebo, and haloperidol were analyzed. The subjects were 523 patients with chronic schizophrenia who, after a 1-week washout period, received placebo, risperidone (2, 6, 10, or 16 mg/day), or haloperidol (20 mg/day) for 8 weeks; the trial was completed by 253 patients. Severity of EPS was assessed by means of the Extrapyramidal Symptom Rating Scale (ESRS). Mean changes (increases) in ESRS scores from baseline to worst score were significantly lower in each risperidone group than the haloperidol group on the total ESRS (parkinsonism + dystonia + dyskinesia), total parkinsonism, hypokinetic symptoms, and on the questionnaire (p < 0.001). On several of the subscales (dyskinesia, buccolinguomasticatory, and Clinical Global Impression severity of dyskinesia), mean change scores were significantly lower in some of the risperidone groups than in the placebo group (p < 0.05). At the clinically most effective risperidone dose (6 mg/day), the mean ESRS change score was not significantly different from that of the placebo group. A significant linear relationship was noted between mean change scores and increasing risperidone dose on 4 of the 12 ESRS subscales; nevertheless, even at 16 mg/day of risperidone, mean change scores were lower than in the haloperidol group. A linear relationship between increasing risperidone dose and use of antiparkinsonian medications was also apparent. Acute dystonic reactions occurred both in patients receiving risperidone and haloperidol. Patients with severe baseline EPS were at higher risk of EPS during the study than patients with low or moderate baseline EPS. It is concluded that low doses of risperidone cause few or no EPS and recommendations for initiation of risperidone treatment are made.


Journal of Clinical Psychopharmacology | 1981

Combined MAOI-tricyclic antidepressant treatment: a reevaluation.

Kerrin White; George M. Simpson

Recent studies have shown that monoamine oxidase inhibitors (MAOIs), in appropriate patients and with proper precautions, are not as dangerous as once thought, especially in comparison to alternative antidepressants. We review the literature regarding the combined use of MAOIs and tricyclic antidepressants, which has been reported to be both highly toxic and highly effective. A large number of reports of adverse effects and their management, uncontrolled clinical trials, and animal studies are summarized. We also discuss the three controlled studies of combined MAOI-tricyclic therapy that have been undertaken. We conclude that the hazards of combination therapy have been exaggerated and that MAOI-tricyclic therapy is a reasonable approach in patients found resistant to standard antidepressant treatment if certain precautions are observed.


Schizophrenia Research | 2004

Improvement in cognitive function following a switch to ziprasidone from conventional antipsychotics, olanzapine, or risperidone in outpatients with schizophrenia

Philip D. Harvey; Herbert Y. Meltzer; George M. Simpson; Steven G. Potkin; Antony Loebel; Cynthia Siu; Steven J. Romano

OBJECTIVE To assess changes in cognitive function in stable outpatients with schizophrenia switched to ziprasidone from conventional antipsychotics (n = 108), olanzapine (n = 104), or risperidone (n = 58) because of suboptimal efficacy or poor tolerability. METHODS In three separate 6-week trials, patients received ziprasidone 40 mg b.i.d. for 2 days, followed by 20-80 mg b.i.d. for the next 40 days. Before switching, and at endpoint, patients were evaluated with tests of working and secondary verbal memory, vigilance, visuomotor speed, verbal fluency, and executive functioning. Principal components factor analysis was performed to test for clustering of cognitive variables. RESULTS Significant improvements were seen at endpoint in secondary verbal memory (in all three groups), vigilance (in patients switched from conventional antipsychotics or risperidone), executive function (in patients switched from conventional antipsychotics or risperidone), and verbal fluency. Factor analysis on baseline scores suggested reduction of the cognitive variables to three factors: verbal skills, attention and short-term memory, and executive functioning. Analysis of z-transformed mean change in factor scores showed significant improvement in verbal skills and global score following the switch from conventional antipsychotics, olanzapine, or risperidone. CONCLUSIONS Patients requiring a change in antipsychotic therapy may exhibit cognitive improvement following a switch to ziprasidone.


Journal of the American Academy of Child and Adolescent Psychiatry | 1999

Antipsychotics in children and adolescents.

Magda Campbell; Judith L. Rapoport; George M. Simpson

OBJECTIVES To present a critical overview of the available evidence for the efficacy and safety of antipsychotic agents in children and adolescents and to identify knowledge gaps and needs for further research. Data from adults that are relevant to children are discussed. METHOD Mainly reports of double-blind, placebo-controlled studies were reviewed. RESULTS In children and adolescents, antipsychotics are used to treat psychotic and a variety of nonpsychotic conditions. The amount of data based on well-designed, double-blind, placebo-controlled studies with satisfactory sample sizes in diagnostically homogeneous subjects is modest. CONCLUSIONS Currently available standard antipsychotics have a definite role in the treatment of children and adolescents. The use of these agents is limited mainly by tardive and withdrawal dyskinesias and, in some patients, by excessive sedation. The atypical antipsychotics should be critically assessed and compared with psychosocial interventions; if effective, the combination of both types of treatments should be evaluated.


Biological Psychiatry | 2003

Predicting suicidal risk in schizophrenic and schizoaffective patients in a prospective two-year trial

Steven G. Potkin; Larry Alphs; Chuanchieh Hsu; K. Ranga Rama Krishnan; Ravi Anand; Frederick Young; Herbert Y. Meltzer; Alan I. Green; Saide Altinsan; Siemion Altman; Likiana Avigo; Richard Balon; Vanda Benešová; Luis Bengochea; István Bitter; Elisabeth Bokowska; Bernardo Carpiniello; Daniel E. Casey; Giovanni B. Cassano; James C.-Y. Chou; Guy Chouinard; Libor Chvila; Jean Dalery; Pedro L. Delgado; Liliana Dell'Osso; Carl Eisdorfer; Robin Emsley; Thomas Fahy; Vera Folnegovic; Sophie Frangou

BACKGROUND Enhanced ability to reliably identify risk factors for suicidal behavior permits more focused decisions concerning treatment interventions and support services, with potential reduction in lives lost to suicide. METHODS This study followed 980 patients at high risk for suicide in a multicenter prospective study for 2 years after randomization to clozapine or olanzapine. A priori predictors related to diagnosis, treatment resistance, and clinical constructs of disease symptoms were evaluated as possible predictors of subsequent suicide-related events. RESULTS Ten baseline univariate predictors were identified. Historical predictors were diagnosis of schizoaffective disorder, history or current use at baseline of alcohol or substance abuse, cigarette smoking, number of lifetime suicide attempts, and the number of hospitalizations in the previous 36 months to prevent suicide. Predictive clinical features included greater baseline scores on the InterSePT scale for suicidal thinking, the Covi Anxiety Scale, the Calgary Depression Scale (CDS), and severity of Parkinsonism. Subsequent multivariate analysis revealed the number of hospitalizations in the previous 36 months, baseline CDS, severity of Parkinsons, history of substance abuse, and lifetime suicide attempts. Clozapine, in general, was more effective than olanzapine in decreasing the risk of suicidality, regardless of risk factors present. CONCLUSIONS This is the first prospective analysis of predictors of suicide risk in a large schizophrenic and schizoaffective population judged to be at high risk for suicide. Assessment of these risk factors may aid clinicians in evaluating risk for suicidal behaviors so that appropriate interventions can be made.


Drugs | 1981

Adverse Effects of Antipsychotic Agents

George M. Simpson; Edmond H. Pi; John J. Sramek

SummaryNeumleptics produce many adverse effects. While some of these are of little import beyond being a nuisance, others are both unusual and potentially serious. Since no consistent reporting mechanism has been established, the exact incidence and severity are often unclear. This article describes adverse effects of neuroleptics in general, but gives special emphasis to those areas which are most relevant at this time. ‘Unwanted’ may be preferable to ‘adverse’ as a term to describe effects which are part of the pharmacological properties of the drug but which may interfere with treatment.Unwanted effects of antipsychotic agents on the central nervous system are an important area for consideration. These include behavioural effects that present as a worsening of the condition being treated or merge with akathisia and produce distinct, recognisable abnormal behaviour that precludes improvement. Extrapyramidal syndromes are of particular importance in patients receiving treatment with antipsychotics, and in particular tardive dyskinesia which recently has gained much attention.The cardiovascular effects of neuroleptics range from hypotension to ECG changes to possible sudden death. As the elderly are more prone to almost all adverse effects, particularly of the cardiovascular and central nervous systems, extra care is recommended in geriatric patients.Endocrine changes producing sexual dysfunction and weight gain may also occur, but careful choice of an antipsychotic drug may help to minimise some of these problems in patients to whom they would be distressful. Other possible methods of diminishing unwanted effects include the measurement of plasma levels of antipsychotics, although at present well-defined therapeutic concentration ranges are not established, with the possible exception of chlorpromazine.Despite a relatively wide range of possible unwanted effects, the benefits of antipsychotic therapy are considerable; adequate knowledge of the potential adverse effects of these agents can improve their benefit to risk ratio even further.

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Jose de Leon

University of the Basque Country

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Jeffrey L. Geller

University of Massachusetts Medical School

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Steven J. Kingsbury

University of Southern California

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