A randomized, double-blind, placebo-controlled study of the safety and tolerability of high-dose quetiapine in patients with persistent symptoms of schizophrenia or schizoaffective disorder

Prevalence and risk factors for metabolic syndrome in schizophrenia, schizoaffective, and bipolar disorder

BACKGROUND

Metabolic Syndrome (MetS) is a risk for developing cardiovascular diseases and its prevalence is especially high in psychiatric patients. To date, there is limited data from the United Arab Emirates (UAE) on the prevalence of MetS. Therefore, we aimed to investigate its prevalence and possible risk factors in a large sample of psychiatric patients in the UAE.

METHODS

A cross-sectional study was conducted at Al-Ain Hospital, in Al-Ain City, UAE. We collected demographic and clinical data on patients diagnosed with schizophrenia, schizoaffective, and bipolar affective disorder in the period between January 2017 and December 2020. This included their secondary diagnosis (psychiatric or medical), vital signs (heart rate, systolic and diastolic blood pressure, Body Mass Index [BMI]), metabolic parameters (fasting blood glucose, cholesterol, triglycerides, low-density lipoprotein, high-density lipoproteins), and prescribed medications. We used the American Association of Clinical Endocrinology (AACE) criteria to diagnose MetS.

RESULTS

We included 889 subjects and of these, 79.8% (N = 709) had a BMI ≥25 kg/m2 and 9.8% (N = 87) had no abnormal metabolic parameters. Overall, 28.1% (N = 250) had MetS with no statistical difference between the three groups. Fasting blood glucose levels and abnormally elevated triglycerides were significant predictors for MetS.

CONCLUSION

Our study found that around one in three patients had MetS irrespective of the three diagnoses. Some variables were significant predictors for MetS. Our findings were consistent with other studies and warrant the need for regular screening and management of abnormal metabolic parameters.

Antipsychotic dose, dopamine D2 receptor occupancy and extrapyramidal side-effects: a systematic review and dose-response meta-analysis

Antipsychotic drugs differ in their propensity to cause extrapyramidal side-effects (EPS), but their dose-effects are unclear. Therefore, we conducted a systematic review and dose-response meta-analysis. We searched multiple electronic databases up to 20.02.2023 for fixed-dose studies investigating 16 second-generation antipsychotics and haloperidol (all formulations and administration routes) in adults with acute exacerbations of schizophrenia. The primary outcome was the number of participants receiving antiparkinsonian medication, and if not available, the number of participants with extrapyramidal side-effects (EPS) and the mean scores of EPS rating scales were used as proxies. The effect-size was odds ratio (ORs) compared with placebo. One-stage random-effects dose-response meta-analyses with restricted cubic splines were conducted to estimate the dose-response curves. We also examined the relationship between dopamine D2 receptor (D2R) occupancy and ORs by estimating occupancies from administrated doses. We included data from 110 studies with 382 dose arms (37193 participants). Most studies were short-term with median duration of 6 weeks (range 3-26 weeks). Almost all antipsychotics were associated with dose-dependent EPS with varied degrees and the maximum ORs ranged from OR = 1.57 95%CI [0.97, 2.56] for aripiprazole to OR = 7.56 95%CI [3.16, 18.08] for haloperidol at 30 mg/d. Exceptions were quetiapine and sertindole with negligible risks across all doses. There was very low quality of findings for cariprazine, iloperidone, and zotepine, and no data for clozapine. The D2R occupancy curves showed that the risk increased substantially when D2R occupancy exceeded 75-85%, except for D2R partial agonists that had smaller ORs albeit high D2R occupancies. In conclusion, we found that the risk of EPS increases with rising doses and differs substantially in magnitude among antipsychotics, yet exceptions were quetiapine and sertindole with negligible risks. Our data provided additional insights into the current D2R therapeutic window for EPS.

Antipsychotic-induced akathisia in adults with acute schizophrenia: A systematic review and dose-response meta-analysis

Antipsychotic-induced akathisia is severely distressing. We aimed to investigate relationships between antipsychotic doses and akathisia risk. We searched for randomised controlled trials that investigated monotherapy of 17 antipsychotics in adults with acute schizophrenia until 06 March 2022. The primary outcome was the number of participants with akathisia, which was analysed with odds ratios (ORs). We applied one-stage random-effects dose-response meta-analyses using restricted cubic splines to model the dose-response relationships. We included 98 studies (343 dose arms, 34,225 participants), most of which were short-term and had low-to-moderate risk of bias. We obtained data on all antipsychotics except clozapine and zotepine. In patients with acute exacerbations of chronic schizophrenia, from moderate to high certainty of evidence, our analysis showed that sertindole and quetiapine carried negligible risks for akathisia across examined doses (flat curves), while most of the other antipsychotics had their risks increase initially with increasing doses and then either plateaued (hyperbolic curves) or continued to rise (monotonic curves), with maximum ORs ranging from 1.76 with 95% Confidence Intervals [1.24, 2.52] for risperidone at 5.4 mg/day to OR 11.92 [5.18, 27.43] for lurasidone at 240 mg/day. We found limited or no data on akathisia risk in patients with predominant negative symptoms, first-episode schizophrenia, or elderly patients. In conclusion, liability of akathisia varies between antipsychotics and is dose-related. The dose-response curves for akathisia in most antipsychotics are either monotonic or hyperbolic, indicating that higher doses carry a greater or equal risk compared to lower doses.

Antipsychotic-Induced Weight Gain: Dose-Response Meta-Analysis of Randomized Controlled Trials

BACKGROUND

Weight gain is among the most important side-effects of antipsychotics. It is, however, unclear whether it is associated with antipsychotic doses. We aimed to fill this gap with a dose-response meta-analysis.

METHODS

We searched multiple electronic databases (last update search June 2021) for all fixed-dose studies that investigated 16 second-generation antipsychotics and haloperidol in adults with acute exacerbation of schizophrenia or with negative symptoms. We estimated the dose-response curves by conducting random-effects dose-response meta-analyses. We used the restricted cubic spline to model the dose-response relationship. The primary outcome was mean weight gain in kg from baseline to endpoint, the secondary outcome was the number of patients with clinically important weight gain.

FINDINGS

Ninety-seven studies with 333 dose arms (36 326 participants) provided data for meta-analyses. Most studies were short-term with median duration of 6 weeks (range 4 to 26 weeks). In patients with acute exacerbation, amisulpride, aripiprazole, brexpiprazole, cariprazine, haloperidol, lumateperone, and lurasidone produced mild weight gain in comparison to placebo (mean difference at any dose≤1 kg), while more significant weight gain was observed by all other drugs. For most drugs, dose-response curves showed an initial dose-related increase in weight which plateaued at higher doses, while for others there was no plateau and some even had bell-shaped curves, meaning less weight gain to be associated with higher doses.

INTERPRETATION

Second-generation antipsychotics do not only differ in their propensity to produce weight gain, but also in the shapes of their dose-response curves. This information is important for dosing decisions in clinical practice.

Effect of Quetiapine, from Low to High Dose, on Weight and Metabolic Traits: Results from a Prospective Cohort Study

INTRODUCTION

The atypical antipsychotic quetiapine is known to induce weight gain and other metabolic complications. The underlying mechanisms are multifactorial and poorly understood with almost no information on the effect of dosage. Concerns were thus raised with the rise in low-dose quetiapine off-label prescription (i. e.,<150 mg/day).

METHODS

In this study, we evaluated the influence of quetiapine dose for 474 patients included in PsyMetab and PsyClin studies on weight and metabolic parameter evolution. Weight, blood pressure, lipid, and glucose profiles were evaluated during a follow-up period of 3 months after treatment initiation.

RESULTS

Significant dose-dependent metabolic alterations were observed. The daily dose was found to influence weight gain and increase the risk of undergoing clinically relevant weight gain (≥7% from baseline). It was also associated with a change in plasma levels of cholesterol (total cholesterol, LDL cholesterol, and HDL cholesterol) as well as with increased odds of developing hypertriglyceridemia, as well as total and LDL hypercholesterolemia. No impact of a dose increase on blood pressure and plasma glucose level was observed.

DISCUSSION

The dose-dependent effect highlighted for weight gain and lipid alterations emphasizes the importance of prescribing the minimal effective dose. However, as the effect size of a dose increase on metabolic worsening is low, the potential harm of low-dose quetiapine should not be dismissed. Prescriptions must be carefully evaluated and regularly questioned in light of side effect onset.

Specific Anti-hostility Effects of Atypical Antipsychotics in Persons with Schizophrenia: From Clozapine to Cariprazine

LEARNING OBJECTIVE

After participating in this activity, learners should be better able to:• Evaluate the anti-hostility effects of available atypical antipsychotic agents.

ABSTRACT

In addition to hallucinations and delusions, persons with schizophrenia may exhibit hostility. In clinical trials of antipsychotics, hostility is routinely measured as part of rating scales such as the Brief Psychiatric Rating Scale or Positive and Negative Syndrome Scale. The availability of the atypical antipsychotic clozapine in 1989 led to the observation that it is possible to have a treatment effect on hostility that is independent of the treatment effect on hallucinations or delusions, and independent of general sedative effects. The data supporting this notion of a specific anti-hostility effect are the most robust for clozapine as the data include specifically designed randomized, controlled clinical trials. A specific anti-hostility effect is also observable to various degrees with most of the other atypical antipsychotics, as evidenced in post hoc analyses of clinical trials originally conducted for regulatory purposes, supplemented by post hoc analyses of large effectiveness trials. The generalizability of these studies, however, may be limited. Participants in these trials were not selected for aggressive and hostile behavior. Some of the studies also excluded patients with substance use disorders. The latter is particularly important because alcohol and substance use are well known to increase risk for hostility and aggression. Nevertheless, the repeated demonstrations of the specificity of an anti-hostility effect (in terms of statistical independence of effects on other positive symptoms and of sedation) are of potential clinical importance.

Dose-Response Meta-Analysis of Antipsychotic Drugs for Acute Schizophrenia

OBJECTIVE

The dose-response relationships of antipsychotic drugs for schizophrenia are not well defined, but such information would be important for decision making by clinicians. The authors sought to fill this gap by conducting dose-response meta-analyses.

METHODS

A search of multiple electronic databases (through November 2018) was conducted for all placebo-controlled dose-finding studies for 20 second-generation antipsychotic drugs and haloperidol (oral and long-acting injectable, LAI) in people with acute schizophrenia symptoms. Dose-response curves were constructed with random-effects dose-response meta-analyses and a spline model. The outcome measure was total score reduction from baseline on the Positive and Negative Syndrome Scale or the Brief Psychiatric Rating Scale. The authors identified 95% effective doses, explored whether higher or lower doses than the currently licensed ones might be more appropriate, and derived dose equivalencies from the 95% effective doses.

RESULTS

Sixty-eight studies met the inclusion criteria. The 95% effective doses and the doses equivalent to 1 mg of oral risperidone, respectively, were as follows: amisulpride for patients with positive symptoms, 537 mg/day and 85.8 mg; aripiprazole, 11.5 mg/day and 1.8 mg; aripiprazole LAI (lauroxil), 463 mg every 4 weeks and 264 mg; asenapine, 15.0 mg/day and 2.4 mg; brexpiprazole, 3.36 mg/day and 0.54 mg; haloperidol, 6.3 mg/day and 1.01 mg; iloperidone, 20.13 mg/day and 3.2 mg; lurasidone, 147 mg/day and 23.5 mg; olanzapine, 15.2 mg/day and 2.4 mg; olanzapine LAI, 277 mg every 2 weeks and 3.2 mg; paliperidone, 13.4 mg/day and 2.1 mg; paliperidone LAI, 120 mg every 4 weeks and 1.53 mg; quetiapine, 482 mg/day and 77 mg; risperidone, 6.3 mg/day and 1 mg; risperidone LAI, 36.6 mg every 2 weeks and 0.42 mg; sertindole, 22.5 mg/day and 3.6 mg; and ziprasidone, 186 mg/day and 30 mg. For amisulpride and olanzapine, specific data for patients with predominant negative symptoms were available. The authors have made available on their web site a spreadsheet with this method and other updated methods that can be used to estimate dose equivalencies in practice.

CONCLUSIONS

In chronic schizophrenia patients with acute exacerbations, doses higher than the identified 95% effective doses may on average not provide more efficacy. For some drugs, higher than currently licensed doses might be tested in further trials, because their dose-response curves did not plateau.

Quetiapine dose optimisation during gestation: a pharmacokinetic modelling study

Objectives

The second-generation antipsychotic quetiapine has been demonstrated to undergo gestation-related changes in pharmacokinetics. This study applied pharmacokinetic modelling principles to investigate the mechanism of these changes and to propose new dosing strategies to counteract these changes.

Methods

A pharmacokinetic modelling approach was implemented using virtual population groups. Changes in quetiapine trough plasma concentration during gestation were quantified across all trimesters, and dose adjustment strategies were applied to counteract these changes by targeting a therapeutic range of 50–500 ng/ml throughout gestation.

Key findings

The application of the model during gestation predicted a decrease in trough concentration. A maximum decrease of 58% was predicted during trimester 2, and being associated with a statistically significant decrease in oral clearance at gestation week 25, 204 l/h ± 100.8 l/h compared with non-pregnant subjects, 121.9 l/h ± 51.8 l/h. A dosing optimisation strategy identified that dose increases to 500–700 mg twice daily would result in 32–55% of subjects possessing trough concentration in excess of 50 ng/ml.

Conclusions

Quetiapine doses in pregnancy should be increased to 500–700 mg twice daily to counteract a concomitant increase in metabolic clearance, increase in volume of distribution and decrease in plasma protein binding.

Increasing antipsychotic dose for non response in schizophrenia

BACKGROUND

Many people with schizophrenia do not reach a satisfactory clinical response with a standard dose of an initially prescribed antipsychotic drug. In such cases, clinicians face the dilemma of increasing the antipsychotic dose in order to enhance antipsychotic efficacy.

OBJECTIVES

To examine the efficacy of increasing antipsychotic dose compared to keeping the same dose in the treatment of people with schizophrenia who have not responded (as defined in the individual studies) to an initial antipsychotic drug trial. We also examine the adverse effects associated with such a procedure.

SEARCH METHODS

We searched the Cochrane Schizophrenia Group Trials Register (10 June 2014, 6 October 2015, and 30 March 2017). We examined references of all included studies for further trials.

SELECTION CRITERIA

All relevant randomised controlled trials (RCTs), reporting useable data, comparing increasing the antipsychotic dose rather than maintaining the original dose for people with schizophrenia who do not respond to their initial antipsychotic treatment.

DATA COLLECTION AND ANALYSIS

At least two review authors independently extracted data . We analysed dichotomous data using relative risks (RR) and the 95% confidence intervals (CI). We analysed continuous data using mean differences (MD) and their 95% CI. We assessed risk of bias for included studies and used GRADE to create a 'Summary of findings' table.

MAIN RESULTS

Ten relevant RCTs with 675 participants are included in this review. All trials were double blind except one single blind. All studies had a run-in phase to confirm they did not respond to their initial antipsychotic treatment. The trials were published between 1980 and 2016. In most studies the methods of randomisation, allocation and blinding were poorly reported. In addition sample sizes were often small, limiting the overall quality of the evidence. Overall, no clear difference was found between groups in terms of the number of participants who showed clinically relevant response (RR 1.09, 95% CI 0.86 to 1.40, 9 RCTs, N = 533, low-quality evidence), or left the study early due to adverse effects (RR 1.63, 95% CI 0.52 to 5.07, very low quality evidence), or due to any reason (RR 1.30, 95% CI 0.89 to 1.90, 5 RCTs, N = 353, low-quality evidence). Similarly, no clear difference was found in general mental state as measured by PANSS total score change (MD -1.44, 95% CI -6.85 to 3.97, 3 RCTs, N = 258, very low quality evidence). At least one adverse effect was equivocal between groups (RR 0.91, 95% CI 0.55 to 1.50, 2 RCTs, N = 191, very low quality evidence). Data were not reported for time in hospital or quality-of-life outcomes. Finally, subgroup and sensitivity analyses did not show any effect on the primary outcome but these analyses were clearly underpowered.

AUTHORS' CONCLUSIONS

Current data do not show any clear differences between increasing or maintaining the antipsychotic dose for people with schizophrenia who do not respond to their initial antipsychotic treatment. Adverse effect reporting was limited and poor. There is an urgent need for further trials in order to determine the optional treatment strategy in such cases.

Increasing antipsychotic dose versus switching antipsychotic for non response in schizophrenia

BACKGROUND

Many people with schizophrenia do not respond to an initially prescribed antipsychotic drug. In such cases, one treatment strategy could be to increase the antipsychotic dose; and another strategy could be to switch to a different antipsychotic drug.

OBJECTIVES

To examine the efficacy of increasing the antipsychotic dose versus switching the antipsychotic drug in the treatment of non-responsive people with schizophrenia.

SEARCH METHODS

We searched the Cochrane Schizophrenia Group Trials Register (10 June 2014, 6 October 2015, and 30 March 2017). We examined references of all included studies for further trials.

SELECTION CRITERIA

All relevant randomised controlled trials (RCTs) comparing increasing the antipsychotic dose versus switching to a different antipsychotic drug for people with schizophrenia who have not responded to their initial antipsychotic treatment.

DATA COLLECTION AND ANALYSIS

At least two review authors independently extracted data. We analysed dichotomous data using relative risks (RR) and their 95% confidence intervals (CIs). We analysed continuous data using mean differences (MD) and their 95% CIs. We assessed risk of bias for included studies and used GRADE to create a 'Summary of findings' table.

MAIN RESULTS

We include one RCT with relevant data on 29 participants in this review. The trial had a parallel design and was double-blind, but blinding procedures were not described. The trial included people who were non-responsive to fluphenazine 20 mg/day administered for 4 weeks. Participants were randomly assigned to continuing treatment with fluphenazine 20 mg/day, increasing the dose to fluphenazine 80 mg/day or switching to haloperidol 20 mg/day for four additional weeks. Data were reported only for 47 out of 58 initially randomised participants. The trial was published in 1993. The fact that only one RCT with a small sample size (N = 29) was included in the analysis limits the quality of the evidence. Overall, no clear difference was found between groups in terms of the three available outcomes: global state (number of participants with clinically relevant response (RR 1.63, 95% CI 0.17 to 15.99, very low quality evidence); general mental state (endpoint score, BPRS total) (MD 2.00, 95% CI -4.20 to 8.20, very low quality evidence); and negative symptoms (endpoint score, SANS) (MD 3.40, 95% CI -12.56 to 19.36). No data were reported for leaving the study early, adverse effects, time in hospital, quality of life, satisfaction with care and functioning.

AUTHORS' CONCLUSIONS

There is extremely limited evidence and no clear conclusions can be drawn. There is an urgent need for further trials in order to determine the optimal treatment strategy for people with schizophrenia who do not respond to their initial antipsychotic treatment.

Treatment of early non-response in patients with schizophrenia: assessing the efficacy of antipsychotic dose escalation

BACKGROUND

Early non-response to antipsychotic treatment in patients with schizophrenia has been shown in multiple studies to predict poor response at short-term trial endpoint. Therefore, strategies to address the challenge of non-improvement early in the course of treatment are needed. A novel trial design was developed to assess the potential utility of antipsychotic dose escalation in patients with an inadequate initial treatment response. This design was embedded in a study intended to assess the efficacy of low dose lurasidone in patients with schizophrenia. The purpose of this report is to describe the background, rationale and design of this study that included a novel method for the assessment of the potential for dose-response in early non-responding patients with schizophrenia.

METHODS/DESIGN

In this 6-week, international, multicenter, double-blind trial, eligible adults with acute schizophrenia were randomized to receive fixed doses of lurasidone 20 mg/day, 80 mg/day (active control), or placebo in a 1:2:1 ratio. Patients initially randomized to lurasidone 80 mg/day who did not have a Positive and Negative Syndrome Scale total score improvement ≥ 20% at Week 2 were re-randomized on a 1:1 basis to receive either lurasidone 80 mg/day or lurasidone 160 mg/day for the remainder of the trial. All other groups remained on their initially assigned treatment. The formal primary objective of the study was to evaluate the efficacy of low-dose lurasidone (20 mg/day) compared to placebo; secondary objectives included evaluating the efficacy of lurasidone 80 mg/day versus 160 mg/day in early non-responders, and evaluating the efficacy of lurasidone in all subjects initially randomized to 80 mg/day versus placebo.

DISCUSSION

Since a lack of early improvement predicts poor response to short-term antipsychotic treatment in patients with schizophrenia, several treatment strategies have been proposed to enhance treatment outcome in early non-responders. A novel clinical trial design involving a placebo arm and re-randomization of early non-responders to increased or maintained antipsychotic dose was developed. The study design described in this report provides a robust method to assess the value of antipsychotic dose escalation in patients with schizophrenia who demonstrate poor initial treatment response.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01821378; initial registration March 22, 2013.

Dose escalation of antipsychotic drugs in schizophrenia: a meta-analysis of randomized controlled trials

BACKGROUND

Non-response to an initial antipsychotic trial emerges frequently in the pharmacological management of schizophrenia. Increasing the dose (high-dose treatment, dose escalation) is an often applied strategy in this regard, but there are currently no meta-analytic data available to ascertain the evidence of this treatment option.

METHODS

We systematically searched for all randomized controlled trials (RCTs) that compared a dose increase directly to the continuation of standard-dose medication in patients with initial non-response to a prospective standard-dose pharmacotherapy with the same antipsychotic compound. Primary outcome was mean change in the Positive and Negative Syndrome Scale (PANSS) or Brief Psychiatric Rating Scale (BPRS) total score. Secondary outcomes were positive and negative symptoms, response rates, and attrition rates. Hedges's g and risks ratios were calculated as effect sizes and the influence of the amount of the dose increase was examined by meta-regressions.

RESULTS

Altogether, five trials with 348 patients investigating dose escalation with quetiapine, ziprasidone, haloperidol, and fluphenazine could be included. We did not find any significant difference for the mean PANSS/BPRS score change between the dose-increase and control group, neither for the pooled antipsychotic group nor for the individual antipsychotic drugs. Moreover, there were no between-group differences in positive and negative symptoms, response rates, and drop-out rates. The meta-regressions indicate no significant influence of the different amounts of dose increments on effect sizes.

CONCLUSIONS

This meta-analysis suggests no evidence for a dose-escalation of the investigated antipsychotic drugs fluphenazine, haloperidol, quetiapine, and ziprasidone in case of initial non-response to standard-dose pharmacotherapy.

Weight gain and antipsychotics: a drug safety review

INTRODUCTION

Second-generation antipsychotics (SGAs) are widely used in several psychiatric disease entities and exert to a different extent a risk for antipsychotic-induced weight gain (AIWG). As AIWG is associated with an increase in metabolic syndrome or cardiovascular events, knowledge of these risks is crucial for further monitoring and the initiation of counteractive measures.

AREAS COVERED

We searched PubMed and Web of Sciences for randomized-controlled trials and naturalistic observational studies published between 2010 and 2014 with sample sizes exceeding 100, including all marketed SGAs apart from zotepine, and providing data on weight increase. We also summarized relevant systematic reviews and meta-analyses of head-to-head comparisons.

EXPERT OPINION

Recently published data still support the hierarchical ranking of SGAs already proposed in previous reviews ranking clozapine and olanzapine as having the highest risk, followed by amisulpride, asenapine, iloperidone, paliperidone, quetiapine, risperidone and sertindole in the middle, and aripiprazole, lurasidone and ziprasidone with the lowest risk. Number needed to harm varied considerably in our meta-analysis. Younger patients and patients with a lower baseline body mass index are most vulnerable. The greatest amount of weight gain occurs within the first weeks of treatment. AIWG occurs in all diagnostic groups and is also common in treatment with first-generation antipsychotics; therefore, awareness of this adverse event is essential for anyone prescribing antipsychotics.

Common use of high doses of antipsychotic medications in older Asian patients with schizophrenia (2001-2009)

OBJECTIVE

This study aimed to examine the use of high doses of antipsychotic medications (≥600 mg/day chlorpromazine equivalent) in older Asian patients with schizophrenia and its demographic and clinical correlates.

METHOD

Information on hospitalized patients with schizophrenia aged ≥50 years was extracted from the database of the Research on Asian Psychotropic Prescription Patterns study (2001-2009). Data on 2203 patients in six Asian countries and territories, including China, Hong Kong, Japan, Korea, Singapore and Taiwan, were analyzed. Socio-demographic and clinical characteristics and antipsychotic prescriptions were recorded.

RESULTS

The frequency for high-dose antipsychotic medications was 36.0% overall, with 38.4% in 2001, 33.3% in 2004 and 36.0% in 2009. Multiple logistic regression analysis of the whole sample showed that compared to patients receiving low-medium antipsychotic doses, those on high doses had a longer illness duration (odds ratio (OR): 2.0, 95% confidence interval (CI):1.2-3.3, p = 0.008), were more likely in the 50-59-year group (OR: 0.95, 95% CI: 0.94-0.97, p < 0.001), more often had current positive (OR: 1.5, 95% CI: 1.2-1.8, p < 0.001) or negative symptoms (OR: 1.3, 95% CI: 1.03-1.6, p = 0.03), and more commonly received antipsychotic polypharmacy (OR: 5.3, 95% CI: 4.1-6.7, p < 0.001). Extrapyramidal symptoms (p = 0.25) and tardive dyskinesia (p = 0.92) were not more frequent in the high-dose group.

CONCLUSIONS

High doses of antipsychotic medications were used in more than one third of older Asian patients with schizophrenia. The reasons for the frequent use of high antipsychotic doses in older Asian patients warrant further investigation.

Quetiapine fumarate for the treatment of multiple sclerosis: focus on myelin repair

Multiple sclerosis (MS) is a central nervous system disorder that is associated with progressive oligodendrocyte and neuronal loss, axonal degeneration, and demyelination. Several medications that mitigate immune abnormalities reduce both the frequency of relapses and inflammation on magnetic resonance imaging, leading to improved outcomes for people with the relapsing-remitting form of MS. However, there are no treatments for the progressive forms of MS where neurons and axons continue to degenerate; here, neuroprotective therapies, or medications that rebuild myelin to confer axonal well-being, may be useful. Quetiapine fumarate is an atypical antipsychotic with reported remyelinating and neuroprotective properties in inflammatory and noninflammatory models of demyelination, including experimental autoimmune encephalomyelitis, and both cuprizone- and global cerebral ischemia-induced demyelination. Preclinical studies suggest that quetiapine may exert these effects by stimulating proliferation and maturation of oligodendrocytes, releasing neurotrophic factors, increasing antioxidant defences, scavenging for free radicals, and inhibiting activated microglia, astrocytes, and T lymphocytes. Additionally, quetiapine may be beneficial for psychiatric and nonpsychiatric symptoms of MS including depression, anxiety, insomnia, and possibly even pain. These data indicate that clinical trials are justified to determine the safety, tolerability, and efficacy of quetiapine fumarate in MS.