Second-generation antipsychotic drugs and extrapyramidal side effects: a systematic review and meta-analysis of head-to-head comparisons

A review on side effect management of second-generation antipsychotics to treat schizophrenia: a drug safety perspective

INTRODUCTION

Effective side effects management present a challenge in antipsychotic treatment with second-generation antipsychotics (SGAs). In recent years, most of the commonly used SGAs, except for clozapine, have been shown to differ only slightly in their effectiveness, but considerably regarding perceived side effects, safety profiles, and compatibility to preexisting medical conditions.

AREAS COVERED

The current state of available evidence on side-effect management in SGA treatment of patients with schizophrenia spectrum disorders (SSD) is reviewed. In addition, current guideline recommendations are summarized, highlighting evidence gaps.

EXPERT OPINION

SGA safety and side effects needs to be considered in treatment planning. Shared decision-making assistants (SDMA) can support patients, practitioners and relatives to orient their decisions toward avoiding side effects relevant to patients' adherence. Alongside general measures like psychosocial and psychotherapeutic care, switching to better tolerated SGAs can be considered a relatively safe strategy. By contrast, novel meta-analytical evidence emphasizes that dose reduction of SGAs can statistically increase the risk of relapse and other unfavorable outcomes. Further, depending on the type and severity of SGA-related side effects, specific treatments can be used to alleviate induced side effects (e.g. add-on metformin to reduce weight-gain). Finally, discontinuation should be reserved for acute emergencies.

Risk of Cardiovascular Events in Schizophrenic Patients Treated with Paliperidone Palmitate Once-Monthly Injection (PP1M): A Population-Based Retrospective Cohort Study in Taiwan

BACKGROUND

Schizophrenia is one of the leading causes of disability. Paliperidone palmitate once-monthly injection (PP1M) was developed to provide consistent drug delivery and improve medication adherence for maintenance treatment. It is well known that patients with schizophrenia have higher cardiovascular risks, however little is known about the cardiovascular risks of patients with schizophrenia treated with PP1M in Asia.

OBJECTIVE

This study aimed to estimate the incidence of cardiovascular events after initiating PP1M treatment and evaluate the cardiovascular risk associations compared with oral second-generation antipsychotics (SGAs).

METHODS

Data from Taiwan's National Health Insurance Research Database were used to identify a cohort of adult patients with schizophrenia who received any SGAs from 1 March 2012 to 31 December 2018. Patients who initiated PP1M treatment were enrolled for descriptive analysis of incidence rates. PP1M patients were propensity matched 1:1 to patients initiating a new oral SGA, for comparative analysis based on demographics, clinical characteristics and treatment history at baseline, in three-step matching procedures, following the prevalent new-user design to enhance comparability. Follow-up ended at the end of the treatment episode of index drug, death, last record available, or end of the study (31 December 2019). Study endpoints included serious cardiovascular events (including severe ventricular arrhythmia and sudden death), expanded serious cardiovascular events (which further included acute myocardial infarction and ischemic stroke), and cardiovascular hospitalizations. Risks of study endpoints between matched cohorts were compared using Cox regression.

RESULTS

Overall, 11,023 patients initiating PP1M treatment were identified (49.5% were females; mean age of 43.2 [12.2] years). Overall incidences for serious cardiovascular events, expanded serious cardiovascular events, and cardiovascular hospitalizations were 3.92, 7.88 and 51.96 per 1000 person-years, respectively. In matched cohort analysis (N = 10,115), the hazard ratios (HRs) between initiating PP1M and a new oral SGA for serious cardiovascular events, expanded serious cardiovascular events, and cardiovascular hospitalizations were 0.86 (95% confidence interval [CI] 0.55-1.36), 0.88 (95% CI 0.63-1.21), and 0.78 (95% CI 0.69-0.89), respectively.

CONCLUSION

This study reported the population-based incidence of cardiovascular events in schizophrenic patients initiating PP1M treatment. PP1M was not associated with increased risks of serious cardiovascular events but was potentially associated with lower risks of cardiovascular hospitalizations compared with oral SGAs.

Real-world predictors of relapse in patients with schizophrenia and schizoaffective disorder in a large health system

Schizophrenia is often characterized by recurring relapses, which are associated with a substantial clinical and economic burden. Early identification of individuals at the highest risk for relapse in real-world treatment settings could help improve outcomes and reduce healthcare costs. Prior work has identified a few consistent predictors of relapse in schizophrenia, however, studies to date have been limited to insurance claims data or small patient populations. Thus, this study used a large sample of health systems electronic health record (EHR) data to analyze relationships between patient-level factors and relapse and model a set of factors that can be used to identify the increased prevalence of relapse, a severe and preventable reality of schizophrenia. This retrospective, observational cohort study utilized EHR data extracted from the largest Midwestern U.S. non-profit healthcare system to identify predictors of relapse. The study included patients with a diagnosis of schizophrenia (ICD-10 F20) or schizoaffective disorder (ICD-10 F25) who were treated within the system between October 15, 2016, and December 31, 2021, and received care for at least 12 months. A relapse episode was defined as an emergency room or inpatient encounter with a pre-determined behavioral health-related ICD code. Patients' baseline characteristics, comorbidities and healthcare utilization were described. Modified log-Poisson regression (i.e. log Poisson regression with a robust variance estimation) analyses were utilized to estimate the prevalence of relapse across patient characteristics, comorbidities and healthcare utilization and to ultimately identify an adjusted model predicting relapse. Among the 8119 unique patients included in the study, 2478 (30.52%) experienced relapse and 5641 (69.48%) experienced no relapse. Patients were primarily male (54.72%), White Non-Hispanic or Latino (54.23%), with Medicare insurance (51.40%), and had baseline diagnoses of substance use (19.24%), overweight/obesity/weight gain (13.06%), extrapyramidal symptoms (48.00%), lipid metabolism disorder (30.66%), hypertension (26.85%), and diabetes (19.08%). Many differences in patient characteristics, baseline comorbidities, and utilization were revealed between patients who relapsed and patients who did not relapse. Through model building, the final adjusted model with all significant predictors of relapse included the following variables: insurance, age, race/ethnicity, substance use diagnosis, extrapyramidal symptoms, number of emergency room encounters, behavioral health inpatient encounters, prior relapses episodes, and long-acting injectable prescriptions written. Prevention of relapse is a priority in schizophrenia care. Challenges related to historical health record data have limited the knowledge of real-world predictors of relapse. This study offers a set of variables that could conceivably be used to construct algorithms or models to proactively monitor demographic, comorbidity, medication, and healthcare utilization parameters which place patients at risk for relapse and to modify approaches to care to avoid future relapse.

Risk Assessment of Psychotropic Drugs on Mitochondrial Function Using In Vitro Assays

Mitochondria are potential targets responsible for some drug- and xenobiotic-induced organ toxicities. However, molecular mechanisms of drug-induced mitochondrial toxicities are mostly unknown. Here, multiple in vitro assays were used to investigate the effects of 22 psychotropic drugs on mitochondrial function. The acute extracellular flux assay identified inhibitors of the electron transport chain (ETC), i.e., aripiprazole, phenytoin, and fluoxetine, an uncoupler (reserpine), substrate inhibitors (quetiapine, carbamazepine, buspirone, and tianeptine), and cytotoxic compounds (chlorpromazine and valproic acid) in HepG2 cells. Using permeabilized HepG2 cells revealed minimum effective concentrations of 66.3, 6730, 44.5, and 72.1 µM for the inhibition of complex-I-linked respiration for quetiapine, valproic acid, buspirone, and fluoxetine, respectively. Assessing complex-II-linked respiration in isolated rat liver mitochondria revealed haloperidol is an ETC inhibitor, chlorpromazine is an uncoupler in basal respiration and an ETC inhibitor under uncoupled respiration (IC50 = 135 µM), while olanzapine causes a mild dissipation of the membrane potential at 50 µM. This research elucidates some mechanisms of drug toxicity and provides some insight into their safety profile for clinical drug decisions.

Neurological soft signs and schizophrenia

Neurological soft signs (NSS) are likely to represent abnormal neurodevelopment and aberration in neural maturation and connectivity. They may not be unique to schizophrenia, but they appear to be a trait characteristic in psychosis and therefore could serve as an objective measure for the assessment of serious psychiatric disorder in the prodromal phase, at onset, and along the course of the disease. Evidence so far proposes that NSS are independent of antipsychotic treatment and therefore constitute a trait symptom, independent of the illness stage and medication. Somatomotor and somatosensory regions, spatial orientation, and visual processing areas, cerebellum, and basal ganglia are implicated as possible structural substrates of NSS. Several studies have examined the relationship between NSS and schizophrenia positive, negative symptoms and deficit syndrome; however, results have been so far ambiguous. Neurocognitive symptoms have been moderately related to NSS suggesting that neurocognitive deficits may contribute to the construct of NSS. Regardless of the fact that NSS are not unique to schizophrenia but extend across to the schizotypy continuum, they may help identify individuals at risk of developing schizophrenia later in life.

Association between psychotropics use and occurrence of falls in hospitalized patients: A matched case-control study

Aim

Understanding the appropriate prescription of psychotropics for hospitalized patients in terms of preventing falls is an important issue. The aim of this study was to assess the associations between the occurrence of falls and the use of various individual psychotropics in hospitalized patients.

Methods

A retrospective matched case-control study was conducted on adult patients admitted to every department of Tokyo Medical University Hospital, with the outcome being in-hospital falls. A total of 447 hospitalized patients who had had in-hospital falls at some point in their hospitalization between January 2016 and December 2016 were included as cases. A total of 447 hospitalized patients who did not have in-hospital falls, and were individually matched to the cases by sex, age, and clinical department, were included as controls. All data were extracted from electronic medical records. Conditional logistic regression analyses were conducted to assess the association between the exposure to 16 psychotropic medications and the occurrence of in-hospital falls. The multivariable logistic regression model adjusted sex, age, clinical department, body mass index, fall risk score on the fall risk assessment measure, and use of psychotropic medications.

Results

The multivariable conditional logistic regression model showed a significant association between the use of risperidone (odds ratio [OR] = 3.730; 95% confidence interval [CI] = 1.229-11.325) and flunitrazepam (OR = 4.120; 95% CI = 1.105-15.364) and an increased OR of falls among hospitalized patients.

Conclusion

The use of risperidone and flunitrazepam were identified as risk factors for falls among hospitalized patients.

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.

Unique effect of clozapine on adenosine A2A-dopamine D2 receptor heteromerization

The striatal dopamine D₂ receptor (D₂R) is generally accepted to be involved in positive symptoms of schizophrenia and is a main target for clinically used antipsychotics. D₂R are highly expressed in the striatum, where they form heteromers with the adenosine A_2A receptor (A_2AR). Changes in the density of A_2AR-D₂R heteromers have been reported in postmortem tissue from patients with schizophrenia, but the degree to which A₂R are involved in schizophrenia and the effect of antipsychotic drugs is unknown. Here, we examine the effect of exposure to three prototypical antipsychotic drugs on A_2AR-D₂R heteromerization in mammalian cells using a NanoBiT assay. After 16 h of exposure, a significant increase in the density of A_2AR-D₂R heteromers was found with haloperidol and aripiprazole, but not with clozapine. On the other hand, clozapine, but not haloperidol or aripiprazole, was associated with a significant decrease in A_2AR-D₂R heteromerization after 2 h of treatment. Computational binding models of these compounds revealed distinctive molecular signatures that explain their different influence on heteromerization. The bulky tricyclic moiety of clozapine displaces TM 5 of D₂R, inducing a clash with A_2AR, while the extended binding mode of haloperidol and aripiprazole stabilizes a specific conformation of the second extracellular loop of D₂R that enhances the interaction with A_2AR. It is proposed that an increase in A_2AR-D₂R heteromerization is involved in the extrapyramidal side effects (EPS) of antipsychotics and that the specific clozapine-mediated destabilization of A_2AR-D₂R heteromerization can explain its low EPS liability.

Single-Nucleotide Polymorphisms as Biomarkers of Antipsychotic-Induced Akathisia: Systematic Review

Antipsychotic-induced akathisia (AIA) is a movement disorder characterized by a subjective feeling of inner restlessness or nervousness with an irresistible urge to move, resulting in repetitive movements of the limbs and torso, while taking antipsychotics (APs). In recent years, there have been some associative genetic studies of the predisposition to the development of AIA. Objective: The goal of our study was to review the results of associative genetic and genome-wide studies and to systematize and update the knowledge on the genetic predictors of AIA in patients with schizophrenia (Sch). Methods: We searched full-text publications in PubMed, Web of Science, Springer, Google Scholar, and e-Library databases from 1977 to 2022. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) quality scale was used for the critical selection of the studies. Results: We identified 37 articles, of which 3 were included in the review. Thus, the C allele of rs1800498 (59414 C>T) and the A allele of rs1800497 (17316 G>A) (TaqIA) from the DRD2 gene as well as the TT genotype rs13212041 (77461407 C>T) from the HTR1B gene were found to be associated with AIA. Conclusions: Uncovering the genetic biomarkers of AIA may provide a key to developing a strategy for the personalized prevention and treatment of this adverse neurological drug reaction of APs in patients with Sch in real clinical practice.

Updated Perspectives on the Management of Drug-Induced Parkinsonism (DIP): Insights from the Clinic

Parkinsonism refers to the clinical combination of bradykinesia, rigidity, tremor, and postural instability. Parkinsonism is often neurodegenerative, but it can be secondary or iatrogenic, as in drug-induced parkinsonism (DIP), which is the topic of this review. We review the pathophysiology of DIP, differentiate DIP and idiopathic Parkinson's disease (PD), list culprit medications in the development of DIP, discuss the diagnosis of DIP as well as the motor and nonmotor signs and symptoms that can help with differentiation of DIP and PD, and detail the management of DIP.

Polypharmacy Management of Antipsychotics in Patients with Schizophrenia

Schizophrenia is a chronic psychiatric disease that is characterized by psychotic symptoms, including positive, negative, affective, and aggressive symptoms, as well as cognitive dysfunction, and is primarily treated using drug therapy, the continuation of which is essential to prevent recurrence/recrudescence. Various second-generation antipsychotics with pharmacological properties or adverse events that differ from those of conventional antipsychotics have recently been introduced, and pharmaceutical management is required for drug efficacy assessments and adverse event monitoring/management of these drugs. Antipsychotic monotherapy (APM) is the gold standard treatment for schizophrenia and is recommended in various guidelines. However, a subgroup of patients with schizophrenia do not or only partially respond to APM. Therefore, antipsychotic polypharmacy (APP), in which ≥2 antipsychotics are combined, has been routinely utilized to compensate for insufficient responses to APM in clinical practice. APP has recently been proposed as an evidence-based treatment option, but does not consider clinicians' experience. However, the risk of APP-related adverse events is high. The application of APP needs to be carefully reviewed, whilst taking into consideration patient backgrounds. Furthermore, the risk of APP-related adverse events is higher in elderly patients than in the general population; therefore, caution is needed. This review discusses the merits of APP, matters that need to be considered, and a switch from APP to APM, and also focuses on the application of APP in clinical practice.

Evolution of antipsychotic-induced extrapyramidal symptoms in patients with schizophrenia in the real-life: A 4-year follow-up naturalistic study

Previous studies have shown, although not consistently, that first generation antipsychotics (FGA) are associated with a prevalence of extrapyramidal symptoms (EPS) higher than second generation antipsychotics (SGA). We assessed the prevalence and the incidence of antipsychotic-induced EPS in a large sample of community-dwelling Italian persons with schizophrenia before and after a 4-year naturalistic treatment, to shed light on their natural evolution and to identify possible predicting factors. EPS and psychopathology were assessed in 571 subjects with schizophrenia before (baseline) and after 4-year follow-up. Patients underwent treatment with SGA and/or FGA according to the referring clinicians' judgment. Relationships between EPS and psychopathology were assessed by network analysis, while a linear multiple regression investigated factors correlated to the presence of EPS at follow-up. EPS were significantly more frequent in the FGA- than in the SGA-treated group, and patients with EPS presented a more severe psychopathology. Parkinsonism was directly and positively connected with poor emotional expression at baseline and with poor emotional expression and disorganization at follow-up. Over the 4-year follow-up, emergent EPS were more frequent in FGA-treated patients, while relieved EPS occurred more frequently in SGA-treated persons. The presence of EPS at follow-up was significantly associated with EPS at baseline, illness duration, antipsychotic generation and the daily dose of antipsychotic medications. After a 4-year naturalistic treatment, EPS disappeared more frequently in SGA-treated patients, while they emerged more frequently in FGA-treated individuals. Therefore, although SGA did not eliminate the risk of EPS, these drugs seem to be associated to a more favorable EPS natural evolution.

Dopamine, Psychosis, and Symptom Fluctuation: A Narrative Review

It has been hypothesized since the 1960s that the etiology of schizophrenia is linked to dopamine. In the intervening 60 years, sophisticated brain imaging techniques, genetic/epigenetic advances, and new experimental animal models of schizophrenia have transformed schizophrenia research. The disease is now conceptualized as a heterogeneous neurodevelopmental disorder expressed phenotypically in four symptom domains: positive, negative, cognitive, and affective. The aim of this paper is threefold: (a) to review recent research into schizophrenia etiology, (b) to review papers that elicited subjective evidence from patients as to triggers and repressors of symptoms such as auditory hallucinations or paranoid thoughts, and (c) to address the potential role of dopamine in schizophrenia in general and, in particular, in the fluctuations in schizophrenia symptoms. The review also includes new discoveries in schizophrenia research, pointing to the involvement of both striatal neurons and glia, signaling pathway convergence, and the role of stress. It also addresses potential therapeutic implications. We conclude with the hope that this paper opens up novel avenues of research and new possibilities for treatment.

Adding pre-emptive anticholinergics to antipsychotics: Is it justified?

Anti-psychotics are the mainstay of treatment for Schizophrenia and psychotic disorders. Historically, anticholinergics have been prescribed to prevent or treat extrapyramidal side effects (EPS) associated with first-generation antipsychotics (FGAs). Even though newer antipsychotics are associated with markedly lower rates of EPS, concurrent anticholinergic use remains high. Use of these medications has potential for long-term side effects, worsening of EPS and poor adherence. We have briefly discussed the limited association between second-generation antipsychotics (SGAs) and EPS, the efficacy of anticholinergics for different types of EPS, and summarized various national and international guidelines on the subject. In conclusion, there is no evidence for prophylactic use of anticholinergics with antipsychotics. Clinicians need to guard against this tendency to be unduly cautious.

Clozapine Use in a Movement Disorder Clinic

BACKGROUND

Clozapine is an effective antipsychotic for Parkinson's disease (PD) that does not worsen motor function and can improve tremor. It is approved for PD psychosis in Europe and Australia.

OBJECTIVE

The aim of this study was to report on the use of clozapine in a movement disorder clinic.

METHODS

We report on patients monitored during the COVID-19 pandemic in clinic over a 7-month period.

RESULTS

Sixty-five patients were seen, of whom 50 had PD. Thirty-one were treated for psychosis, 18 for refractory tremor and 1 for levodopa dyskinesias. The remainder had psychotic symptoms with dementia with Lewy bodies (n = 2) or other movement disorders. Four had clozapine discontinued because of sedation and 1 for agranulocytosis. Three had clozapine temporarily halted because of granulocytopenia but were rechallenged successfully.

CONCLUSIONS

When comparing clozapine use in this clinic as compared with others, we deduce that clozapine is likely significantly underutilized in the United States.

Association of Treatment With Antipsychotics, Antidepressants, or Both With Movement Disorders and Seizures Among Children and Adolescents With Depression in Korea

IMPORTANCE

Little evidence exists on neurological adverse events (movement disorders and seizures) that occur during adjuvant use of antipsychotics with antidepressants, especially in children and adolescents.

OBJECTIVE

To assess the association between neurological adverse events (movement disorders, including parkinsonism, dystonia, extrapyramidal symptoms, chorea, and tic, and seizures) and the adjuvant use of antipsychotics in children and adolescents with depression.

DESIGN, SETTING, AND PARTICIPANTS

A retrospective cohort study using the Health Insurance Review and Assessment claims database in Korea between 2008 and 2018. The study population was children and adolescents aged 2 to 18 years with depression who began treatment with antidepressants between January 1, 2010, and December 31, 2018. Data were analyzed between December 9, 2020, and December 10, 2021.

EXPOSURE

Time-varying exposure to antidepressants, antipsychotics, and concomitant use of antidepressants and antipsychotics. Concomitant use was further subdivided according to the antipsychotic treatment status (dose and agent).

MAIN OUTCOMES AND MEASURES

The extended Cox proportional hazards regression model, with adjustment for sex, age, health insurance type, psychiatric comorbidities, psychiatric hospitalization, and comedication with other psychotropic drugs, was used to estimate adjusted hazard ratios (aHRs) and 95% CIs for the associations of movement disorders and seizures with use of antidepressants and antipsychotics.

RESULTS

A total of 9890 patients were included in the study: 9541 (mean [SD] age, 14.8 [2.8] years; 4956 [51.9%] female) and 7731 (mean [SD] age, 14.9 [2.7] years; 4150 [53.7%] female) met the inclusion criteria for movement disorders and seizures, respectively. For movement disorders, associations were found between concomitant use (aHR, 3.68; 95% CI, 3.06-4.44) and antipsychotic-only use (aHR, 3.84; 95% CI, 3.03-4.87) compared with antidepressant-only use, but their CIs overlapped. The associations with seizure were similar (concomitant use: aHR, 2.06; 95% CI, 1.66-2.55; antipsychotic-only use: aHR, 2.05; 95% CI, 1.53-2.75). With concomitant use, the aHRs gradually increased with increasing doses of antipsychotics. Haloperidol had the highest aHR, 7.15 (95% CI, 3.89-10.00) for movement disorders. The highest aHR for seizure was observed with quetiapine (aHR, 2.36; 95% CI, 1.55-3.59), followed by aripiprazole (aHR, 2.05; 95% CI, 1.52-2.77).

CONCLUSIONS AND RELEVANCE

In this cohort study, adjunctive antipsychotics with antidepressants were associated with movement disorders and seizures compared with antidepressant monotherapy in children and adolescents with depression. These results suggest that careful consideration of the risk-benefit profile of the antipsychotic use as adjuvant therapy in this population is needed.

Half a century of research on antipsychotics and schizophrenia: A scientometric study of hotspots, nodes, bursts, and trends

Changes over 50 years of research on antipsychotics in schizophrenia have occurred. A scientometric synthesis of such changes over time and a measure of researchers' networks and scientific productivity is currently lacking. We searched Web of Science Core Collection from inception until November 5, 2021, using the appropriate key. Our primary objective was to conduct systematic mapping with CiteSpace to show how clusters of keywords have evolved over time and obtain clusters' structure and credibility. Our secondary objective was to measure research network performance (countries, institutions, and authors) using CiteSpace, VOSviewer, and Bibliometrix. We included 32,240 studies published between 1955 and 2021. The co-cited reference network identified 25 clusters with a well-structured network (Q=0.8166) and highly credible clustering (S=0.91). The main trends of research were: 1) antipsychotic efficacy; 2) cognition in schizophrenia; 3) side effects of antipsychotics. Last five years research trends were: 'ultra-resistance schizophrenia' (S=0.925), 'efficacy/dose-response' (S=0.775), 'evidence-synthesis' (S=0.737), 'real-world effectiveness' (S=0.794), 'cannabidiol' (S=0.989), and 'gut microbiome' (S=0.842). These results can inform funding agencies and research groups' future directions.

Antipsychotic Drug-Induced Increases in Peripheral Catecholamines are Associated With Glucose Intolerance

The second-generation antipsychotic drugs are widely used in the field of psychiatry, for an expanding number of different conditions. While their clinical efficacy remains indispensable, many of the drugs can cause severe metabolic side-effects, resulting in an increased risk of developing cardiometabolic disorders. The physiological basis of these side-effects remains an ongoing area of investigation. In the present study, we examined the potential role of peripheral catecholamines in antipsychotic-induced glucose intolerance. Adult female rats were acutely treated with either the first-generation antipsychotic drug haloperidol (0.1, 0.5 or 1 mg/kg) or the second-generation drugs risperidone (0.25, 1.0 or 2.5 mg/kg), olanzapine (1.5, 7.5 or 15 mg/kg) or clozapine (2, 10 or 20 mg/kg) or vehicle. Fasting glucose levels were measured and then animals were subjected to the intraperitoneal glucose tolerance test. Levels of peripheral norepinephrine, epinephrine and dopamine were concurrently measured in the same animals 75, 105 and 135 min after drug treatment. All antipsychotics caused glucose intolerance, with strongest effects by clozapine > olanzapine > risperidone > haloperidol. Plasma catecholamines were also increased by drug treatment, with greatest effects for norepinephrine and epinephrine caused by clozapine > risperidone > olanzapine > haloperidol. Importantly, there were strong and statistically significant associations between norepinephrine/epinephrine levels and glucose intolerance for all drugs. These findings confirm that increases in peripheral catecholamines co-occur in animals that exhibit antipsychotic-induced glucose intolerance, and these effects are strongly associated with each other, providing further evidence for elevated catecholamines as a substrate for antipsychotic metabolic side-effects.

Systematic literature review of schizophrenia clinical practice guidelines on acute and maintenance management with antipsychotics

Clinical practice guidelines (CPGs) translate evidence into recommendations to improve patient care and outcomes. To provide an overview of schizophrenia CPGs, we conducted a systematic literature review of English-language CPGs and synthesized current recommendations for the acute and maintenance management with antipsychotics. Searches for schizophrenia CPGs were conducted in MEDLINE/Embase from 1/1/2004–12/19/2019 and in guideline websites until 06/01/2020. Of 19 CPGs, 17 (89.5%) commented on first-episode schizophrenia (FES), with all recommending antipsychotic monotherapy, but without agreement on preferred antipsychotic. Of 18 CPGs commenting on maintenance therapy, 10 (55.6%) made no recommendations on the appropriate maximum duration of maintenance therapy, noting instead individualization of care. Eighteen (94.7%) CPGs commented on long-acting injectable antipsychotics (LAIs), mainly in cases of nonadherence (77.8%), maintenance care (72.2%), or patient preference (66.7%), with 5 (27.8%) CPGs recommending LAIs for FES. For treatment-resistant schizophrenia, 15/15 CPGs recommended clozapine. Only 7/19 (38.8%) CPGs included a treatment algorithm.

Factors influencing the outcome of integrated therapy approach in schizophrenia: A narrative review of the literature

The integration of pharmacotherapy with psychosocial interventions has an important role to play in the improvement of functional outcome of subjects with schizophrenia (SCZ), in all stages of the disorder. It is essential for the adequate management of unmet therapeutic needs, such as negative symptoms and cognitive dysfunctions which account for most of the functional impairment of subjects with SCZ and do not respond to available antipsychotics. Enhancing the knowledge on factors involved in the effectiveness of integrated treatment plans is an important step forward for SCZ care. This review aims to identify factors that might influence the impact of integrated treatments on functional outcome. Most studies on the impact of psychosocial treatments on functional outcome of subjects with SCZ did not control for the effect of prescribed antipsychotics or concomitant medications. However, several factors relevant to ongoing pharmacological treatment might influence the outcome of integrated therapy, with an impact on the adherence to treatment (e.g., therapeutic alliance and polypharmacotherapy) or on illness-related factors addressed by the psychosocial interventions (e.g., cognitive dysfunctions or motivational deficits). Indirect evidence suggests that treatment integration should consider the possible detrimental effects of different antipsychotics or concomitant medications on cognitive functions, as well as on secondary negative symptoms. Cognitive dysfunctions can interfere with participation to an integrated treatment plan and can be worsened by extrapyramidal or metabolic side effects of antipsychotics, or concomitant treatment with anticholinergics or benzodiazepines. Secondary negative symptoms, due to positive symptoms, sedation, extrapyramidal side effects or untreated depression, might cause early drop-out and poor adherence to treatment. Researchers and clinicians should examine all the above-mentioned factors and implement appropriate and personalized integrated treatments to improve the outcome of SCZ.

Cariprazine's Potential in Improving Social Dysfunction in Patients With Schizophrenia: A Perspective

Social dysfunction is one of the most debilitating aspects of schizophrenia. Treatment of this complex phenomenon, constituted by negative, cognitive, and affective symptoms, has been difficult with the available pharmacological agents, hence it represents an unmet medical need. Cariprazine, a novel, third-generation antipsychotic with a unique mechanism of action has been proven to sufficiently alleviate negative, cognitive, and affective symptoms of schizophrenia. These characteristics make this compound a valid candidate for addressing social dysfunction too. In this perspective, we argue that cariprazine can be viewed as a "socializing drug" that has the ability to improve the patient's functionality and ultimately their quality of life. Data from animal research, clinical trials, an observational study, and patient cases are provided.

Depicting Safety Profile of TAAR1 Agonist Ulotaront Relative to Reactions Anticipated for a Dopamine D2-Based Pharmacological Class in FAERS

Background and Objectives

In clinical trials, the safety of drugs is summarized by the incidence of adverse events, while post-marketing reporting systems use disproportionate reporting of adverse drug reactions. Here, we propose a method to evaluate the novelty of a safety profile of a drug in a new class (in clinical trials), against that of those already on the market (using pharmacovigilance data).

Methods

Through Bayesian disproportionality analyses of the US Food and Drug Administration Adverse Event Reporting System (FAERS) data, we identified and ranked Preferred Terms for a pool of 30 antipsychotics. Adverse event rates in randomized, double-blind, placebo-controlled schizophrenia clinical trials were summarized by their class specificity. One study (N = 245) of the trace amine-associated receptor 1 (TAAR1) agonist ulotaront (SEP-363856) was compared with five studies of dopamine D2 receptor-based antipsychotics lurasidone (N = 1041), quetiapine (N = 119), olanzapine (N = 122), and placebo (N = 504).

Results

In clinical trials of antipsychotics, cumulative rates for adverse events at and above a threshold of disproportional reporting (Empirical Bayes Geometric Mean 50 > 3 in FAERS) were 52%, 42%, and 60% for lurasidone, quetiapine, and olanzapine, respectively, indicating that over half of the adverse events reported in clinical trials of an atypical antipsychotic are class-specific risks. In contrast, in the clinical trial of ulotaront, the cumulative rate was 23%, indicating a lower rate of antipsychotic class-specific risk.

Conclusions

These results demonstrate a novel approach to summarize adverse events in clinical trials, where the cumulative burden of class-specific risks describes the emerging safety profile of a new drug in clinical development, relative to reactions anticipated for drugs in an established pharmacological class.

ClinicalTrials.gov Identifiers

NCT0296938, NCT00088634, NCT00549718, NCT00615433, NCT00790192.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40261-021-01094-7.

The effect of second-generation antipsychotic withdrawal on the occurrence of vacuous chewing movements in animal models: A review

INTRODUCTION

Abrupt discontinuation of antipsychotics is associated with an increased risk of adverse events such as extrapyramidal symptoms in humans. In animal models, vacuous chewing movements may occur after antipsychotic discontinuation. We aim to assess vacuous chewing movements after the discontinuation of second-generation antipsychotics in animal models.

METHODS

PubMed, EMBASE, and Web of Science databases were searched for studies since inception until January 2, 2021. In addition, we manually searched references from included and relevant studies. Studies were included if a behavioral assessment of vacuous chewing movements (VCMs) in animal models was performed after discontinuation of a second-generation antipsychotic (SGA). Findings will be reviewed qualitatively and discussed with regard to clinical implications.

RESULTS

5607 studies were screened and five studies were considered eligible for the qualitative analysis. The five studies reported results of behavioral assessments of VCMs after discontinuation of clozapine, olanzapine, and risperidone. VCMs were not reported to be increased after discontinuation of clozapine and olanzapine. However, VCMs were reported to be increased after discontinuation of higher but not lower dosages of risperidone.

DISCUSSION

These findings, based on a limited series of studies, suggest differences in the occurrence of extrapyramidal symptoms between second-generation antipsychotics. More research is needed to determine the magnitude of differences between antipsychotics and implications for clinical practice in humans.

Use of antipsychotics and long-term risk of parkinsonism

INTRODUCTION

Few epidemiological studies have assessed the risk of parkinsonisms after prolonged use of neuroleptics. We aimed to examine the long-term risk of degenerative parkinsonisms (DP) associated with previous use of neuroleptics.

METHODS

All residents in Piedmont, Northern-west Italy, older than 39 years (2,526,319 subjects), were retrospectively followed up from 2013 to 2017. Exposure to neuroleptics was assessed through the regional archive of drug prescriptions. The development of DP was assessed using the regional archives of both drug prescriptions and hospital admissions. We excluded prevalent DP cases at baseline as well as those occurred in the first 18 months (short-term risk). The risk of DP associated with previous use of neuroleptics was examined through Cox regression, using a matched cohort design.

RESULTS

The risk of DP was compared between 63,356 exposed and 316,779 unexposed subjects. A more than threefold higher risk of DP was observed among subjects exposed to antipsychotics, compared to those unexposed (HR = 3.27, 95% CI 3.00-3.57), and was higher for exposure to atypical than typical antipsychotics. The risk decreased after 2 years from therapy cessation but remained significantly elevated (HR = 2.38, 95% CI 1.76-3.21).

CONCLUSIONS

These results indicate a high risk of developing DP long time from the start of use and from the cessation for both typical and atypical neuroleptics, suggesting the need of monitoring treated patients even after long-term use and cessation.

Role of COMT V158M Polymorphism in the Development of Dystonia after Administration of Antipsychotic Drugs

Antipsychotics (APDs) represent the main pharmacological strategy in the treatment of schizophrenia; however, their administration often may result in severe adverse effects, such as extrapyramidal symptoms. Typically, dystonic movements are considered the result of impaired function and/or abnormalities of dopaminergic neurotransmission/signaling in the basal ganglia. The catechol O-methyltransferase (COMT) gene is located within the 22q11.2 region, and its product is an enzyme involved in transferring a methyl group from S-adenosylmethionine to catecholamines, including dopamine. Studies showed that COMT Val158Met polymorphism modifies enzymatic activity and, consequently, synaptic dopamine concentration in specific brain areas. We identified a patient with 22q11.2 deletion syndrome presenting with cervical and trunk dystonia after paliperidone administration, which persisted even after drug discontinuation. Given the patient’s genetic condition, we hypothesized that the dopaminergic dysfunction had been aggravated by COMT involvement, thus causing dystonia. In line with this hypothesis, we carried out a study on psychiatric patients in chronic treatment with APD to evaluate the distribution of the COMT Val158Met polymorphism and its role in the onset of adverse extrapyramidal symptoms. The study included four patients with dystonia after administration of APDs compared to 17 patients who never presented adverse drug reactions. Our data suggest that the Val/Val and Met/Met polymorphisms of the COMT gene are associated with a protective effect for the development of collateral extrapyramidal symptoms in patients treated with APDs, while the Val/Met genotype could be considered a risk factor for the development of dystonia after APDs administration.

Efficacy and safety of clozapine in psychotic disorders-a systematic quantitative meta-review

A recent increase in the literature regarding the evidence base for clozapine has made it increasingly difficult for clinicians to judge "best evidence" for clozapine use. As such, we aimed at elucidating the state-of-the-art for clozapine with regard to efficacy, effectiveness, tolerability, and management of clozapine and clozapine-related adverse events in neuropsychiatric disorders. We conducted a systematic PRISMA-conforming quantitative meta-review of available meta-analytic evidence regarding clozapine use. Primary outcome effect sizes were extracted and transformed into relative risk ratios (RR) and standardized mean differences (SMD). The methodological quality of meta-analyses was assessed using the AMSTAR-2 checklist. Of the 112 meta-analyses included in our review, 61 (54.5%) had an overall high methodological quality according to AMSTAR-2. Clozapine appears to have superior effects on positive, negative, and overall symptoms and relapse rates in schizophrenia (treatment-resistant and non-treatment-resistant subpopulations) compared to first-generation antipsychotics (FGAs) and to pooled FGAs/second-generation antipsychotics (SGAs) in treatment-resistant schizophrenia (TRS). Despite an unfavorable metabolic and hematological adverse-event profile compared to other antipsychotics, hospitalization, mortality and all-cause discontinuation (ACD) rates of clozapine surprisingly show a pattern of superiority. Our meta-review outlines the superior overall efficacy of clozapine compared to FGAs and most other SGAs in schizophrenia and suggests beneficial efficacy outcomes in bipolar disorder and Parkinson's disease psychosis (PDP). More clinical studies and subsequent meta-analyses are needed beyond the application of clozapine in schizophrenia-spectrum disorders and future studies should be directed into multidimensional clozapine side-effect management to foster evidence and to inform future guidelines.

Recommendations of the schizophrenia expert center network for the screening prevention and treatment of sleep disorders based on the results from the real-world schizophrenia FACE-SZ national cohort

BACKGROUND

Sleep disorders associated factors are under explored in schizophrenia while the literature suggests high and heterogeneous frequency.

AIMS

The objective of the present study was to determine the prevalence and risk factors of sleep disorders in the real-world FACE-SZ national cohort.

METHOD

Stabilized schizophrenic outpatients were recruited in 10 expert centers for schizophrenia. Sleep quality was explored with the Pittsburgh Sleep Quality Index (PSQI) and sleep disorders was defined by a PSQI score > 5. Psychosis severity was measured with the Positive and Negative Syndrome Scale, current major depressive episode with the Calgary Depression Scale for Schizophrenia, verbal aggressiveness with the Buss-Perry Aggression Questionnaire, adherence to treatment with the Medication Adherence Rating Scale, akathisia with the Barnes Akathisia Scale. Current somatic comorbidities and body mass index were reported. Variables with P values <0.20 in univariate analysis were included in a multivariate regression model.

RESULTS

Of the 562 included patients, 327 subjects (58.2%, IC95% [54.1% - 62.3%]) reported having sleep disorders. After adjustment, sleep disorders were significantly associated with migraine (adjusted odds ratio aOR = 2.23, p = 0.041), major depressive disorder (aOR 1.79, p = 0.030), poor adherence to treatment (aOR = 0.87, p = 0.006), akathisia (aOR = 1.29, p = 0.042) and verbal aggressiveness (aOR = 1.09, p = 0.002).

CONCLUSIONS

More than one on two stabilized real-life outpatients with schizophrenia have been identified with sleep disorders. Combined with the literature data, we have yielded expert recommendations for the treatment and prevention of sleep disorders including treating undiagnosed comorbid depression and migraine and managing antipsychotic treatment to improve adherence and akathisia.

Prevalence of antipsychotic-induced extrapyramidal symptoms and their association with neurocognition and social cognition in outpatients with schizophrenia in the "real-life"

First generation antipsychotics (FGAs) are more likely to induce extrapyramidal side-effects (EPS) than second generation antipsychotics (SGAs), and EPS have been shown associated to cognitive deficits in schizophrenia. So far, no study has explored the relationships between EPS and social cognition (SC) in people with schizophrenia. Therefore, we assessed the prevalence of EPS in a large sample of drug-treated community-dwelling persons with schizophrenia and explored their relationships with patients' neurocognitive and SC abilities. 875 patients underwent EPS, psychopathological, neurocognitive and SC assessments by means of standardized measures. Relationships between EPS, psychopathology and neurocognitive and SC measures were investigated by correlation tests. Moreover, a partial correlation network was computed by means of a network analysis. 256 patients were treated with FGAs alone or in combination with SGA and 619 with SGAs. EPS were significantly more frequent in FGA-treated group than in the SGA-treated one. Patients with EPS disclosed a more severe psychopathology and were more impaired in neurocognitive and SC measures compared to those without EPS. Disorganization, expressive deficit, and duration of illness were significantly associated to both neurocognitive and SC measures while EPS were associated to neurocognitive measures only. The network analysis showed that parkinsonism was the sole EPS directly connected to both psychopathological and neurocognitive indices whereas no direct connection emerged between EPS and SC measures. Present findings confirm that EPS are still present in the era of SGAs and contribute, together with other clinical variables, to the neurocognitive but not to the SC impairment of patients with schizophrenia.

Treatment patterns and appropriateness of antipsychotic prescriptions in patients with schizophrenia

Schizophrenia is a chronic mental condition presenting a wide range of symptoms. Although it has a low prevalence compared to other mental conditions, it has a negative impact on social and occupational functions. This study aimed to assess the appropriateness of antipsychotic medications administered to schizophrenic patients and describe current treatment patterns for schizophrenia. A retrospective cohort study was conducted in all patients over the age of 15 with an active diagnosis of schizophrenia and treated with antipsychotics between 2008 and 2013 in the Valencia region. A total of 19,718 patients were eligible for inclusion. The main outcome assessed was inappropriateness of the pharmacotherapeutic management, including polypharmacy use. Altogether, 30.4% of patients received antipsychotic polypharmacy, and 6.8% were prescribed three or more antipsychotics. Overdosage affected 318 individuals (1.6%), and 21.5% used concomitant psychotropics without an associated psychiatric diagnosis. Women and people with a comorbid condition like anxiety or depression were less likely to receive antipsychotic polypharmacy. In contrast, increased polypharmacy was associated with concomitant treatment with other psychoactive drugs, and only in user on maintenance therapy, with more visits to the mental health hospital. Overall, we observed a high level of inappropriateness in antipsychotic prescriptions. Greater adherence to guidelines could maximize the benefits of antipsychotic medications while minimizing risk of adverse effects.

Akathisia as an Extrapyramidal Side Effect of Fluoxetine

Fluoxetine is a selective serotonin reuptake inhibitor (SSRI) that is commonly prescribed for major depressive disorder (MDD). Akathisia is one of the well-recognized extrapyramidal symptoms (EPS) of antipsychotics and antiemetics, but also a rare manifestation of antidepressants. There are various documentations of EPS of antidepressants including acute dystonia, Parkinsonism, and tardive dyskinesia. Akathisia is not only a rare extrapyramidal manifestation of fluoxetine but a frequently unrecognized phenomenon in those using this medication. This case report describes a case of akathisia observed in a 69-year-old Caucasian female using fluoxetine. Various factors that may have contributed to the development of akathisia in this patient were also discussed as well as implications for clinical practice and future research.

Antipsychotics result in more weight gain in antipsychotic naive patients than in patients after antipsychotic switch and weight gain is irrespective of psychiatric diagnosis: A meta-analysis

Introduction

Antipsychotics are associated with bodyweight gain and metabolic disturbance. Previous meta-analyses were limited to mainly antipsychotic switch studies in patients with a diagnosis of schizophrenia or psychosis with short follow-up periods. The present meta-analysis aimed to analyse the impact of weight change in antipsychotic-naive and antipsychotics switch patients and whether body weight change depended on diagnosis.

Method

We performed a meta-analysis of clinical trials of antipsychotics that reported weight change, irrespective of psychiatric diagnosis. Outcome measure was body weight change. Studies were classified into antipsychotic-naive and antipsychotic-switch. Forest plots stratified by antipsychotic and the duration of antipsychotic use were generated and results were summarised in figures.

Results

In total, 404 articles were included for the quantitative synthesis. 58 articles were on antipsychotic naive patients. In the antipsychotic naive group, all antipsychotics resulted in body weight gain. In the antipsychotic switch group, most antipsychotics likewise resulted in bodyweight gain, with exception of amisulpride, aripiprazole and ziprasidone that showed no body weight gain or even some weight loss after switching antipsychotics. Diagnosis was not a discriminating factor of antipsychotic induced weight change.

Conclusion

Antipsychotic use resulted in substantial increase in body weight in antipsychotic-naive patients. In antipsychotic-switch patients the weight gain was mild and not present in amisulpride, aripiprazole and ziprasidone. In both groups, weight gain was irrespective of the psychiatric diagnosis.

Treatment of Antipsychotic-Induced Akathisia: Role of Serotonin 5-HT2a Receptor Antagonists

Akathisia is one of the most prevalent and distressing adverse effects associated with antipsychotic drug treatment. Propranolol, a non-selective beta-adrenergic receptor antagonist, is currently considered a first-line treatment for antipsychotic-induced akathisia (AIA). Surprisingly, the evidence for its anti-akathisia effect is modest. Propranolol's side effects (e.g. orthostatic hypotension, bradycardia), contraindications (e.g. asthma) and increased complexity in titration schedules limit its use in some patients. Anticholinergic agents and benzodiazepines merely provide symptomatic relief in patients with AIA. Effective and well-tolerated treatment remains a major unmet need in akathisia and warrants a search for new anti-akathisia agents. Accumulating evidence during the last two decades indicates that agents with marked postsynaptic serotonin 5-HT_2a receptor antagonism (ritanserin, cyproheptadine, trazodone, mianserin, mirtazapine) may represent a new class of potential anti-akathisia remedies. Among these agents, low-dose mirtazapine (7.5 mg or 15 mg once daily) has demonstrated the most compelling evidence for therapeutic efficacy. In this narrative review we highlight the clinical significance of AIA, outline major approaches for its management and propose a practical algorithm for its treatment.

Dose-Dependent Efficacy of Aripiprazole in Treating Patients With Schizophrenia or Schizoaffective Disorder: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Purpose: To compare the efficacy and tolerability of different administration strategies of aripiprazole. Methods: We searched MEDLINE, EMBASE, the Cochrane Central, Web of Science, China National Knowledge Infrastructure(CNKI), and Wanfang Data Knowledge Service Platform(Wanfang) for randomized controlled trials (RCTs) of aripiprazole, using the terms: (aripiprazole) AND (schizophr^* OR schizoaff^*) AND ("syndrome scale" OR PANSS) AND (clini^* OR trial). We retrieved study design, participant characteristics, comparison groups, and outcomes from each study. Results: In total, nine RCTs were selected for meta-analysis, which covered ~1,187 participants. We defined two treatment groups that represent different treatment strategies: (1) the high-dose group (the high-dose strategy) rapidly increased to doses higher than 15 mg/day in 2 weeks or began with doses higher than 15 mg/day, otherwise the group was defined as (2) the low-dose group (the low-dose strategy). If the initial or target doses of aripiprazole in a study were all higher than 15 mg/day, the high- and low-dose groups were created based on the relative level of the dose. The high-dose group showed significantly greater reductions in Positive and Negative Syndrome Scale (PANSS) total scores (standardized mean differences = -8.31, 95% confidence interval [CI] = -16.48, -0.13; P < 0.01; I ² = 96%) than the low-dose group. The high-dose group showed superior effects compared with the low-dose group in long-term studies (more than 8 weeks) (standardized mean differences = -13.81, 95% CI = -25.07, -2.55; P < 0.01; I ² = 96%). With exception of somnolence, we did not find significant differences in side effects or discontinuation due to adverse events. Sensitivity analyses produced similar results. Conclusion: The high-dose treatment strategy of aripiprazole for patients with schizophrenia or schizoaffective disorder may bring more benefits without obvious side effects.

Effects of Transcranial Direct Current Stimulation (tDCS) in the Normalization of Brain Activation in Patients with Neuropsychiatric Disorders: A Systematic Review of Neurophysiological and Neuroimaging Studies

Background

People with neuropsychiatric disorders have been found to have abnormal brain activity, which is associated with the persistent functional impairment found in these patients. Recently, transcranial direct current stimulation (tDCS) has been shown to normalize this pathological brain activity, although the results are inconsistent.

Objective

We explored whether tDCS alters and normalizes brain activity among patients with neuropsychiatric disorders. Moreover, we examined whether these changes in brain activity are clinically relevant, as evidenced by brain-behavior correlations.

Methods

A systematic review was conducted according to PRISMA guidelines. Randomized controlled trials that studied the effects of tDCS on brain activity by comparing experimental and sham control groups using either electrophysiological or neuroimaging methods were included.

Results

With convergent evidence from 16 neurophysiological/neuroimaging studies, active tDCS was shown to be able to induce changes in brain activation patterns in people with neuropsychiatric disorders. Importantly, anodal tDCS appeared to normalize aberrant brain activation in patients with schizophrenia and substance abuse, and the effect was selectively correlated with reaction times, task-specific accuracy performance, and some symptom severity measures. Limitations and Conclusions. Due to the inherent heterogeneity in brain activity measurements for tDCS studies among people with neuropsychiatric disorders, no meta-analysis was conducted. We recommend that future studies investigate the effect of repeated cathodal tDCS on brain activity. We suggest to clinicians that the prescription of 1-2 mA anodal stimulation for patients with schizophrenia may be a promising treatment to alleviate positive symptoms. This systematic review is registered with registration number CRD42020183608.

Continuous versus extended antipsychotic dosing in schizophrenia: Less is more

Antipsychotic drugs temper psychotic symptoms by interacting with dopamine D2 receptors to reduce dopamine neurotransmission. Currently, the standard of care involves antipsychotic treatment protocols that achieve steady-state levels of medication. Maintaining patients on continuous treatment is thought to be necessary to keep them stabilised. However, continuous antipsychotic exposure increases the risk of adverse effects over time. These effects include metabolic and cardiovascular disorders, extrapyramidal complications, and dopamine receptor supersensitivity, the latter of which could potentially promote both treatment tolerance and psychosis relapse. In the present review, we describe evidence showing that continuous exposure to antipsychotic drugs can not only worsen long-term outcome, but-past acute phase treatment-it is also unnecessary to effectively manage schizophrenia symptoms. We also describe evidence that regular but extended dosing, allowing predictable periods of lower antipsychotic levels/D2 occupancy, is both safe and effective in patients, and it greatly reduces drug exposure overall. Studies in laboratory animals show that compared to continuous antipsychotic exposure, regular but extended dosing actually has superior antipsychotic-like efficacy, and it also substantially reduces the likelihood of both motor side effects and dopamine receptor supersensitivity. We propose that regular, but extended dosing should be considered in the long-term treatment of people with schizophrenia, because the available evidence suggests it can be just as effective as continuous treatment, while decreasing overall drug exposure and potentially reducing harmful side effects.

A Comprehensive Review on Importance and Quantitation of Atypical Antipsychotic Drugs and their Active Metabolites in Commercial Dosage Forms

Background:

Schizophrenia is a severe mental illness that affects more than twenty-one million people throughout the world. Schizophrenia also causes early death. Schizophrenia and other related psychotic ailments are controlled by the prescription of antipsychotic drugs, which act by blocking certain chemical receptors in the brain and thus relieves the symptoms of psychotic disorder. These drugs are present in the different dosage forms in the market and provided in a certain amount as per the need of the patients.

Objective:

Since such medications treat mental disorders, it is very important to have a perfect and accurate dose so that the risk factor is not affected by a higher or lower dose, which is not sufficient for the treatment. For accurate assay of these kinds of drugs, different analytical methods were developed ranging from older spectrophotometric techniques to latest hyphenated methods.

Results:

The current review highlights the role of different analytical techniques that were employed in the determination and identification of antipsychotic drugs and their metabolites. Techniques such as spectrophotometry, fluorimetry, liquid chromatography, liquid chromatography-mass spectrometry, gas chromatography, and gas chromatography-mass spectrometry employed in the method development of such antipsychotic drugs were reported in the review. Different metabolites, identified using the hyphenated techniques, were also mentioned in the review. The synthesis pathways of few of the metabolites were mentioned.

Conclusion:

The review summarizes the analyses of different antipsychotic drugs and their metabolites. A brief introduction of illnesses and their symptoms and possible medications were highlighted. Synthesis pathways of the associated metabolites were also mentioned.

Heteromer formation between cannabinoid type 1 and dopamine type 2 receptors is altered by combination cannabinoid and antipsychotic treatments

The cannabinoid type 1 (CB₁ ) receptor and the dopamine type 2 (D₂ ) receptor are co-localized on medium spiny neuron terminals in the globus pallidus where they modulate neural circuits involved in voluntary movement. Physical interactions between the two receptors have been shown to alter receptor signaling in cell culture. The objectives of the current study were to identify the presence of CB₁ /D₂ heteromers in the globus pallidus of C57BL/6J male mice, define how CB₁ /D₂ heteromer levels are altered following treatment with cannabinoids and/or antipsychotics, and determine if fluctuating levels of CB₁ /D₂ heteromers have functional consequences. Using in situ proximity ligation assays, we observed CB₁ /D₂ heteromers in the globus pallidus of C57BL/6J mice. The abundance of the heteromers increased following treatment with the nonselective cannabinoid receptor agonist, CP55,940. In contrast, treatment with the typical antipsychotic haloperidol reduced the number of CB₁ /D₂ heteromers, whereas the atypical antipsychotic olanzapine treatment had no effect. Co-treatment with CP55,940 and haloperidol had similar effects to haloperidol alone, whereas co-treatment with CP55,940 and olanzapine had similar effects to CP55,940. The observed changes were found to have functional consequences as the differential effects of haloperidol and olanzapine also applied to γ-aminobutyric acid release in STHdh^Q7/Q7 cells and motor function in C57BL/6J male mice. This work highlights the clinical relevance of co-exposure to cannabinoids and different antipsychotics over acute and prolonged time periods.

Risperidone-Induced Acute Laryngeal Dystonia: A Case Report

BACKGROUND Antipsychotic medications are associated with multiple adverse effects, including metabolic syndrome, prolonged QT interval, and extrapyramidal symptoms. Acute laryngeal dystonia (ALD) is a rare and lethal form of extrapyramidal reaction. CASE REPORT A 27-year-old woman with schizophrenia on risperidone presented to our Emergency Department with a sensation of choking and respiratory distress, mimicking a panic attack. She developed a generalized dystonic reaction in the hospital, leading to diagnosis risperidone-associated ALD as a cause of her initial problems. She was discharged with an emphasis on being compliant with anticholinergic medication. However, her persistent respiratory symptoms prompted us to revisit the management plan. Her risperidone dose was tapered down to discontinue and an alternate drug was chosen. CONCLUSIONS ALD must be considered as a differential diagnosis when patients on antipsychotic medications present with respiratory distress. Our case highlights the association of ALD with an atypical antipsychotic agent, risperidone. Prompt recognition of this entity is necessary to prevent complications and guide definitive management.

A Systematic Review and Case Series of Ziprasidone for Psychosis in Parkinson's Disease

The atypical antipsychotic ziprasidone has been considered inappropriate for use in patients with Parkinson’s disease (PD), as most atypical antipsychotics worsen parkinsonism. However, the current evidence for safety and efficacy of ziprasidone in PDP has not been evaluated in a systematic fashion. We review published experience with ziprasidone for treating psychosis in PD via systematic search of MEDLINE, Embase, Cochrane CENTRAL, and Clinicaltrials.gov with terms related to “ziprasidone” and “Parkinson’s disease”, inclusive of case reports and prospective studies. We also add seven cases of ziprasidone exposure in patients in our center with idiopathic PD or Lewy body dementia (DLB), selected by retrospective query of all clinical data since 1996. In our review, two prospective trials and 11 case reports or series were found, with ziprasidone found to be generally effective for treatment of psychosis and with few adverse events reported. Our case series did not support efficacy of ziprasidone; it was generally safe in PD, but two patients with DLB had adverse motor events. We conclude that, although ziprasidone occasionally can produce substantial worsening of motor signs, it usually is well tolerated, and may provide in some cases a useful alternative to quetiapine, clozapine and pimavanserin, particularly in the acute care setting. Further randomized controlled studies are needed.

Phosphodiesterases PDE2A and PDE10A both change mRNA expression in the human brain with age, but only PDE2A changes in a region-specific manner with psychiatric disease

Many studies implicate altered cyclic nucleotide signaling in the pathophysiology of major depressive disorder (MDD), bipolar disorder (BPD), and schizophrenia (SCZ). As such, we explored how phosphodiesterases 2A (PDE2A) and 10A (PDE10A)-enzymes that break down cyclic nucleotides-may be altered in brains of these patients. Using autoradiographic in situ hybridization on postmortem brain tissue from the Stanley Foundation Neuropathology Consortium, we measured expression of PDE2 and PDE10 mRNA in multiple brain regions implicated in psychiatric pathophysiology, including cingulate cortex, orbital frontal cortex (OFC), superior temporal gyrus, hippocampus, parahippocampal cortex, amygdala, and the striatum. We also assessed how PDE2A and PDE10A expression changes in these brain regions across development using the Allen Institute for Brain Science Brainspan database. Compared to controls, patients with SCZ, MDD and BPD all showed reduced PDE2A mRNA in the amygdala. In contrast, PDE2A expression changes in frontal cortical regions were only significant in patients with SCZ, while those in caudal entorhinal cortex, hippocampus, and the striatum were most pronounced in patients with BPD. PDE10A expression was only detected in striatum and did not differ by disease group; however, all groups showed significantly less PDE10A mRNA expression in ventral versus dorsal striatum. Across development, PDE2A mRNA increased in these brain regions; whereas, PDE10A mRNA expression decreased in all regions except striatum. Thus, PDE2A mRNA expression changes in both a disorder- and brain region-specific manner, potentially implicating PDE2A as a novel diagnostic and/or patient-selection biomarker or therapeutic target.

20-year follow-up study of physical morbidity and mortality in relationship to antipsychotic treatment in a nationwide cohort of 62,250 patients with schizophrenia (FIN20)

Antipsychotics are effective in preventing relapses of schizophrenia, but it is generally believed that their long-term use is harmful for patients' physical well-being. However, there are no long-term studies which have verified this view. This nationwide, register-based cohort study aimed to assess the risk of hospitalization due to physical health problems, as a marker for severe physical morbidity, and the risk of all-cause mortality, as well as of cardiovascular and suicidal death, associated with antipsychotic use in all patients treated for schizophrenia in inpatient care between 1972 and 2014 in Finland (N=62,250), with up to 20 years of follow-up (median: 14.1 years). The use of antipsychotic drugs (i.e., use of any antipsychotic compared with non-use) and the use of specific antipsychotics were investigated, and outcomes were somatic and cardiovascular hospitalization, and all-cause, cardiovascular and suicide death. Hospitalization-based outcomes were analyzed by a within-individual design to eliminate selection bias, comparing use and non-use periods in the same individual by stratified Cox model. Mortality outcomes were assessed by traditional between-individual Cox multivariate models. The adjusted hazard ratios (aHRs) for any somatic hospitalization and cardiovascular hospitalization were 1.00 (95% CI: 0.98-1.03) and 1.00 (95% CI: 0.92-1.07) during use of any antipsychotic compared to non-exposure periods within the same individual. The aHRs were 0.48 (95% CI: 0.46-0.51) for all-cause mortality, 0.62 (95% CI: 0.57-0.67) for cardiovascular mortality, and 0.52 (95% CI: 0.43-0.62) for suicide mortality during use vs. non-use of any antipsychotic. The most beneficial mortality outcome was associated with use of clozapine in terms of all-cause (aHR=0.39, 95% CI: 0.36-0.43), cardiovascular (aHR=0.55, 95% CI: 0.47-0.64) and suicide mortality (aHR=0.21, 95% CI: 0.15-0.29). The cumulative mortality rates during maximum follow-up of 20 years were 46.2% for no antipsychotic use, 25.7% for any antipsychotic use, and 15.6% for clozapine use. These data suggest that long-term antipsychotic use does not increase severe physical morbidity leading to hospitalization, and is associated with substantially decreased mortality, especially among patients treated with clozapine.

Differential Effects of Acute Treatment With Antipsychotic Drugs on Peripheral Catecholamines

Antipsychotic drugs represent the most effective treatment for chronic psychotic disorders. The newer second generation drugs offer the advantage of fewer neurological side-effects compared to prior drugs, but many cause serious metabolic side-effects. The underlying physiology of these side-effects is not well-understood, but evidence exists to indicate that the sympathetic nervous system may play an important role. In order to examine this possibility further, we treated separate groups of adult female rats acutely with either the first generation antipsychotic drug haloperidol (0.1 or 1 mg/kg) or the second generation drugs risperidone (0.25 or 2.5 mg/kg), clozapine (2 or 20 mg/kg), olanzapine (3 or 15 mg/kg) or vehicle by intraperitoneal injection. Blood samples were collected prior to drug and then 30, 60, 120, and 180 mins after treatment. Plasma samples were assayed by HPLC-ED for levels of norepinephrine, epinephrine, and dopamine. Results confirmed that all antipsychotics increased peripheral catecholamines, although this was drug and dose dependent. For norepinephrine, haloperidol caused the smallest maximum increase (+158%], followed by risperidone (+793%), olanzapine (+952%) and clozapine (+1,684%). A similar pattern was observed for increases in epinephrine levels by haloperidol (+143%], olanzapine (+529%), risperidone (+617%) then clozapine (+806%). Dopamine levels increased moderately with olanzapine [+174%], risperidone [+271%], and clozapine [+430%]. Interestingly, levels of the catecholamines did not correlate strongly with each other prior to treatment at baseline, but were increasingly correlated after treatment as time proceeded. The results demonstrate antipsychotics can potently regulate peripheral catecholamines, in a manner consistent with their metabolic liability.

Treatment of posttraumatic stress disorder: Focus on pharmacotherapy

Current clinical practice guidelines for the treatment of posttraumatic stress disorder offer varying recommendations regarding the use of pharmacotherapy. Many direct head-to-head comparisons of pharmacotherapy are lacking, and recommendations are based on meta-analyses and small trials. While selective serotonin reuptake inhibitors and serotonin norepinephrine reuptake inhibitors are considered first-line pharmacotherapy, clear distinctions do not exist when considering other classes of psychotropic medications. Ultimately, when selecting an appropriate medication for a patient diagnosed with posttraumatic stress disorder, the clinician needs to consider the current symptomatology being experienced, comorbid conditions, and evidence for efficacy of specific treatments prior to initiating medications.

Influence of magnesium supplementation and L-type calcium channel blocker on haloperidol-induced movement disturbances

Haloperidol (Hal) is an antipsychotic related to movement disorders. Magnesium (Mg) showed benefits on orofacial dyskinesia (OD), suggesting its involvement with N-methyl-D-aspartate receptors (NMDAR) since it acts blocking calcium channels. Comparisons between nifedipine (NIF; a calcium channel blocker) and Mg were performed to establish the Mg mechanism. Male rats concomitantly received Hal and Mg or NIF for 28 days, and OD behaviors were weekly assessed. Both Mg and NIF decreased Hal-induced OD. Hal increased Ca²⁺-ATPase activity in the striatum, and Mg reversed it. In the cortex, both Mg and NIF decreased such activity. Dopaminergic and glutamatergic immunoreactivity were modified by Hal and treatments: i) in the cortex: Hal reduced D1R and D2R, increasing NMDAR immunoreactivity. Mg and NIF reversed this Hal influence on D1R and NMDAR, while only Mg reversed Hal effects on D2R levels; ii) in the striatum: Hal decreased D2R and increased NMDAR while Mg and NIF decreased D1R and reversed the Hal-induced decreasing D2R levels. Only Mg reversed the Hal-induced increasing NMDAR levels; iii) in the substantia nigra (SN): while Hal increased D1R, D2R, and NMDAR, both Mg and NIF reversed this influence on D2R, but only Mg reversed the Hal-influence on D1R levels. Only NIF reversed the Hal effects on NMDAR immunoreactivity. These findings allow us to propose that Mg may be useful to minimize Hal-induced movement disturbances. Mg molecular mechanism seems to be involved with a calcium channel blocker because the NIF group showed less expressive effects than the Mg group.

Discovery and Development of Non-Dopaminergic Agents for the Treatment of Schizophrenia: Overview of the Preclinical and Early Clinical Studies

Schizophrenia is a chronic psychiatric disorder that affects about 1 in 100 people around the world and results in persistent emotional and cognitive impairments. Untreated schizophrenia leads to deterioration in quality of life and premature death. Although the clinical efficacy of dopamine D2 receptor antagonists against positive symptoms of schizophrenia supports the dopamine hypothesis of the disease, the resistance of negative and cognitive symptoms to these drugs implicates other systems in its pathophysiology. Many studies suggest that abnormalities in glutamate homeostasis may contribute to all three groups of schizophrenia symptoms. Scientific considerations also include disorders of gamma-aminobutyric acid-ergic and serotonergic neurotransmissions as well as the role of the immune system. The purpose of this review is to update the most recent reports on the discovery and development of non-dopaminergic agents that may reduce positive, negative, and cognitive symptoms of schizophrenia, and may be alternative to currently used antipsychotics. This review collects the chemical structures of representative compounds targeting metabotropic glutamate receptor, gamma-aminobutyric acid type A receptor, alpha 7 nicotinic acetylcholine receptor, glycine transporter type 1 and glycogen synthase kinase 3 as well as results of in vitro and in vivo studies indicating their efficacy in schizophrenia. Results of clinical trials assessing the safety and efficacy of the tested compounds have also been presented. Finally, attention has been paid to multifunctional ligands with serotonin receptor affinity or phosphodiesterase inhibitory activity as novel strategies in the search for dedicated medicines for patients with schizophrenia.