Clozapine Monitoring in Clinical Practice: Beyond the Mandatory Requirement

Evidence for the Role of the Mitochondrial ABC Transporter MDL1 in the Uptake of Clozapine and Related Molecules into the Yeast Saccharomyces cerevisiae

Clozapine is an antipsychotic drug whose accumulation in white cells can sometimes prove toxic; understanding the transporters and alleles responsible is thus highly desirable. We used a strategy in which a yeast (Saccharomyces cerevisiae) CRISPR-Cas9 knock-out library was exposed to cytotoxic concentrations of clozapine to determine those transporters whose absence made it more resistant; we also recognised the structural similarity of the fluorescent dye safranin O (also known as safranin T) to clozapine, allowing it to be used as a surrogate marker. Strains lacking the mitochondrial ABC transporter MDL1 (encoded by YLR188W) showed substantial resistance to clozapine. MDL1 overexpression also conferred extra sensitivity to clozapine and admitted a massive increase in the cellular and mitochondrial uptake of safranin O, as determined using flow cytometry and microscopically. Yeast lacking mitochondria showed no such unusual accumulation. Mitochondrial MDL1 is thus the main means of accumulation of clozapine in S. cerevisiae. The closest human homologue of S. cerevisiae MDL1 is ABCB10.

Influence of Lifestyle Factors on Metabolic Syndrome in Psychiatric Patients Attending a Community Mental Health Setting: A Cross-sectional Study

Background

Metabolic syndrome (MetS) is a concern in psychiatric patients. We aimed to study the influence of the modifiable lifestyle factors on MetS in adult psychiatric patients along with associated clinical factors and quality of life.

Methods

Factors such as diet (Healthy Eating Index), exercise, substance use, cardiovascular risk (QRISK), illness severity (Clinical Global Impression), medications, adverse events (Systematic Monitoring of Adverse Events Related to Treatments), and quality of life (Recovering Quality of Life Scale) were assessed along with clinical components for MetS in 323 psychiatric patients receiving routine care and monitoring in a Community Mental Health Team.

Results

MetS was present in 50.5% (95% CI: 45.0-55.9). It was significantly associated with higher age, duration of mental illness, body mass index (BMI), QTc, QRISK, and antipsychotic drugs. In logistic regression, age, QTc, QRISK, and BMI remained significantly linked to MetS. Patients with or without MetS were comparable in their lifestyle factors such as diet, exercise, and substance use, along with the family history of metabolic disorders, age at onset of mental illness, duration of antipsychotic medication, side effects, psychiatric diagnoses, and quality of life. However, many patients with or without MetS had poorer diet and physical inactivity, indicating scope for interventions.

Conclusions

Around half of the psychiatric patients had MetS, and modifiable lifestyle factors did not differentiate individuals with or without MetS. The need for further research on the prevention and management of MetS in psychiatric patients is highlighted.

A proposal for reducing maximum target doses of drugs for psychosis: Reviewing dose-response literature

BACKGROUND

Presently, there is limited guidance on the maximal dosing of psychosis drugs that is based on effectiveness rather than safety or toxicity. Current maximum dosing recommendations may far exceed the necessary degree of dopamine D2 receptor blockade required to treat psychosis. This may lead to excess harm through cognitive impairment and side effects.

AIMS

This analysis aimed to establish guidance for prescribers by optimally dosing drugs for psychosis based on efficacy and benefit.

METHODS

We used data from two dose-response meta-analyses and reviewed seven of the most prescribed drugs for psychosis in the UK. Where data were not available, we used appropriate comparison techniques based on D2 receptor occupancy to extrapolate our recommendations.

RESULTS

We found that the likely threshold dose for achieving remission of psychotic symptoms was often significantly below the currently licensed dose for these drugs. We therefore recommend that clinicians are cautious about exceeding our recommended doses. Individual factors, however, should be accounted for. We outline potentially relevant factors including age, ethnicity, sex, smoking status and pharmacogenetics. Additionally, we recommend therapeutic drug monitoring as a tool to determine individual pharmacokinetic variation.

CONCLUSIONS

In summary, we propose a new set of maximum target doses for psychosis drugs based on efficacy. Further research through randomised controlled trials should be undertaken to evaluate the effect of reducing doses from current licensing maximums or from doses that are above our recommendations. However, dose reductions should be implemented in a manner that accounts for and reduces the effects of drug withdrawal.

Clozapine clinical toolkit optimizes inpatient clozapine monitoring

Introduction

Clozapine is the most effective antipsychotic in the management of treatment-resistant schizophrenia; however, its use is challenging due to the risk of severe adverse effects. Despite the risks associated with clozapine, there is no mandatory monitoring in Canada beyond hematologic testing for agranulocytosis surveillance. This study focuses on the development, implementation, and evaluation of a clozapine clinical toolkit (CTK) targeted at optimizing inpatient clozapine use.

Methods

A comprehensive literature review was conducted to identify clozapine best practices, experts were consulted, and a comprehensive clozapine CTK was developed and implemented at a large Canadian tertiary hospital in December 2018. To evaluate the CTK, a retrospective chart review was conducted to assess for change in guideline-concordant monitoring pre- and post- CTK implementation. Patients were included if they were > 18 years of age and received clozapine during inpatient admission. Results were analyzed using descriptive and inferential statistics.

Results

Among the charts reviewed, 185 and 113 admissions met the pre- and post-CTK inclusion criteria, respectively. Staff used the CTK in the care of 96% of clozapine patients post implementation, and its use resulted in improvements in guideline-concordant monitoring for agranulocytosis and myocarditis.

Discussion

Implementation of the clozapine CTK increased the concordance of clozapine monitoring with best practice recommendations. Future research is necessary to assess the impact of the CTK on clinical outcomes and patient satisfaction.

Management of Cholinergic Rebound After Abrupt Withdrawal of Clozapine: A Case Report and Systematic Literature Review

BACKGROUND

Cholinergic discontinuation symptoms, also known as "cholinergic rebound," from abrupt clozapine discontinuation are characterized by a range of somatic and psychiatric symptoms.

OBJECTIVE

The objective of this study was to describe the clinical features and management options for clozapine withdrawal-associated cholinergic rebound syndrome (henceforth referred to as CWCRS) and present an illustrative case report.

METHODS

Based on a literature search of the databases PubMed, OVID Medline, and Embase as well as reviewing reference lists of relevant past reviews, we carried out a systematic review of case reports on the management of CWCRS from 1946 to 2023.

RESULTS

We identified 10 previously published articles on the clinical management of CWCRS, with a total of 18 patients (6 female, 12 male) with an average age of 43 years (standard deviation 14). Half of the patients had a history of tardive dyskinesia. The mean dose of clozapine before discontinuation was 351 mg/day, with duration of clozapine treatment ranging from 3 weeks to 9 years. Clozapine was the most effective treatment, followed by benztropine.

CONCLUSIONS

Given the small number of cases and the nonexperimental nature of the available studies, this review could not provide reliable data to guide management of CWCRS. The findings, however, suggest that clozapine may be more effective than other commonly used treatment options. With the high rates of discontinuation among patients on clozapine, there is a pressing need for further research into the epidemiology, natural history, and management of clozapine withdrawal syndromes.

[Safety aspects during treatment with clozapine. : Monitoring and rechallenge - a narrative review]

BACKGROUND

Due to its unique efficacy in treatment-resistant schizophrenia, discontinuation of treatment with clozapine is frequently associated with a significant worsening of symptoms, but also with an increased risk of suicide. Based on the literature, this review aims at summarizing different monitoring recommendations in order to be able to continue this therapy despite the occurrence of side effects. In addition, we provide recommendations when rechallenge of a previously stopped treatment with clozapine can be considered and when a definite discontinuation must take place.

MATERIAL AND METHODS

Medline, the Guideline for the use of clozapine 2013 of the Netherlands Clozapine Collaboration Group, and the S3 Guideline for Schizophrenia of the German Association of Psychiatry, Psychotherapy and Psychosomatics were searched for relevant literature, the last query dating from April 28th, 2023.

RESULTS

If agranulocytosis or cardiomyopathy develops, treatment with clozapine must be discontinued and should not be resumed thereafter. In contrast, treatment with clozapine which had to be discontinued due to myocarditis or prolongation of the QTc interval may be continued if left ventricular function is normal or after normalization of the QTc interval. Other side effects are usually not absolute contraindications for rechallenge but often require the adjunctive use of additional pharmacologic and non-pharmacologic measures.

CONCLUSION

Taking into consideration various monitoring recommendations, cessation of treatment with clozapine can often be prevented or treatment with clozapine that has been discontinued due to side effects can be resumed.

Prognostic Value of CYP1A2 (rs2069514 and rs762551) Polymorphisms in COVID-19 Patients

The aim of the study was to examine the genotype-allele determination of CYP1A2 rs2069514 and rs762551 polymorphisms in patients with mild and severe COVID-19 and to determine their effectiveness as prognostic criteria in COVID-19. The study consists of 60 patients who were hospitalized in intensive care or outpatient treatment due to COVID-19 in Istanbul NP Brain Hospital between 2020-2021. Genotyping was conducted by Real-Time PCR. Age (p<0.001); chronic disease (p=0.002); cardiovascular disease (p=0.004); respiratory distress (p<0.001); neurological disease (p=0.004); fatigue (p=0.048); loss of taste and smell (p=0.003); nausea/vomiting (p=0.026); intubated (p<0.001); ground glass image (p<0.001) and CYP1A2 genotypes (p<0.001) showed a statistically significant difference between patients with and without intensive care admission. According to multivariate logistic regression analysis, CYP1A2 *1A/*1C + *1C/*1C genotypes (OR:5.23 95% CI: 1.22-22.36; p=0.025), chronic disease (OR:4.68 95% CI:1.14-19.15; p=0.032) or patients at 65 years or older (OR:5.17, 95%CI:1.26-21.14; p=0.022) increased the risk of admission to the intensive care unit. According to our results, we strongly suggest considering the CYP1A2 rs2069514 and rs762551 polymorphisms as important predictors of Intensive Care Unit admission in patients with COVID-19, and we also suggest that genotype results will guide clinicians for the benefit and the efficiency of the treatment.

A case-control study of antipsychotic use and pneumonia-related mortality in the United Kingdom

BACKGROUND AND AIM

There is increasing evidence linking antipsychotic use with pneumonia, but limited evidence of an effect on pneumonia-related outcomes such as mortality. In this study, we aimed to examine the association of pneumonia-related death with specific antipsychotic exposure.

METHOD

Deaths analysed were those reported to a UK-based drug-related deaths database, the National Programme on Substance Abuse Deaths (NPSAD), between 1997 and September 2020. We conducted a case-control study with cases defined as pneumonia-related deaths and controls as cases with alternative causes of death. Cases were analysed by considering drugs detected at post-mortem (PM) and by drugs prescribed to the deceased at the time of their death with calculated odds ratios (ORs) adjusted to account for confounders.

RESULTS

There were 2467 PM cases and 40,128 controls; 1818 prescribed cases and 28,018 controls. Second generation antipsychotics (SGAs) were robustly associated with an increased risk of pneumonia-related death compared with those not prescribed or taking antipsychotics (PM detection adjusted OR [AOR] 1·34 [95% CI 1·15-1·55]; prescribed AOR 1·28 [95% CI 1·11-1·49]). First generation antipsychotics had no clear association with death from pneumonia (PM detection AOR 1·06 [95% CI 0·77-1·47]; prescribed AOR 0·91 [95% CI 0·71-1·17]). Amongst SGAs, olanzapine was associated with an increased risk of death due to pneumonia (PM detection AOR 1·49 [95% CI 1·22-1·82]; prescribed AOR 1·44 [95% CI 1·18-1·76]) as was quetiapine (PM detection AOR 1·34 [95% CI 1·07-1·66]; prescribed AOR 1·28 [95% CI 1·01-1·64]).

CONCLUSION

Olanzapine and quetiapine were found to increase the risk of pneumonia-related death in this NPSAD sample to a clinically important extent.

Metabolic Syndrome in Adults Receiving Clozapine; The Need for Pharmacist Support

People who are diagnosed with treatment resistant schizophrenia (TRS) are likely to have clozapine as a therapeutic management option. There is a high prevalence of metabolic syndrome in patients receiving clozapine. To mitigate against this, monitoring of weight, waist circumference, lipid profile, glycated haemoglobin (HbA1c), fasting blood glucose (FBG) and blood pressure (BP) is recommended. The aims of this study were to examine the prevalence of metabolic syndrome and whether any variables were correlated with its development, and to highlight any opportunities for the pharmacist to offer support. This study was conducted in an urban hospital and its associated Clozapine Clinic in Cork, Ireland. A retrospective audit assessed the prevalence of metabolic syndrome using the International Diabetes Federation (IDF) criteria. Patients were eligible for inclusion if they were aged 18 years or more, registered with the Clozapine Clinic, and had the capacity to provide informed consent. All data were entered into Microsoft^® Excel ^® (Microsoft Corporation) and further statistical analysis was undertaken using R, t-tests, Fisher's Exact Test and Mann-Whitney U tests as appropriate, and p ≤ 0.05 was considered statistically significant. Of 145 patients (32% female; mean age (SD) 45.3 (±11.7) years; 86.2% living independently/in family home), nearly two thirds (n = 86, 59.3%) were diagnosed with metabolic syndrome. The mean age of participants with metabolic syndrome was 44.4 years (SD = 10.8), similar to the 46.6 years (SD = 12.8) for those without. Variables that were identified to be statistically significantly associated with metabolic syndrome included waist circumference, weight, triglycerides, high density lipoprotein-cholesterol (HDL-C), BP, FBG and HbA1c. The high incidence of metabolic syndrome in this patient population highlights the need for continued physical health monitoring of these patients to ameliorate the risk of developing metabolic syndrome.

Clozapine Blood Concentration Predicts Corrected QT-Interval Prolongation in Patients With Psychoses

BACKGROUND

Corrected QT-interval (QTc) prolongation (QTP) is a rare but fatal adverse effect of antipsychotics. Clozapine is the only antipsychotic recommended for treatment of resistant schizophrenia; however, clozapine has been reported to cause QTP. We sought factors predictive of QTP in patients who had antipsychotic polypharmacy involving clozapine. We explored whether the clozapine blood concentration might predict QTP.

METHODS

We included 133 patients with schizophrenia spectrum disorder who had antipsychotic polypharmacy involving clozapine. We used the χ2 and nonparametric tests to compare clozapine therapeutic drug monitoring (TDM) values and QTc-prolonged person (QTPP) status. Multivariate regression and mediator models were used to identify risk factors for QTPP status and QTP.

RESULTS

In total, 111 patients were prescribed clozapine. The QTPP rates were 31.3% (20) for men and 23.2% (16) for women. Compared with the non-QTPP group, the QTPP group exhibited significantly higher daily dose of all antipsychotics including clozapine, a higher clozapine dose, and elevated clozapine and norclozapine TDM values. Furthermore, such patients were prescribed a greater number of antipsychotics. Multivariate logistic regression revealed that only the clozapine TDM value could be predictive factor for QTPP status (P = 0.018). A clozapine TDM value above the therapeutic range (>600 mg/dL) was associated with a high risk of QTPP status (adjusted odds ratio, 6.5; 95% confidence interval, 1.7-25.2; P = 0.006). The mediator model revealed that the clozapine TDM values completely mediated the association between the clozapine dose and the QTc interval.

CONCLUSIONS

The clozapine blood concentration reliably predicts QTP in patients with clozapine use.

Factors predicting serum clozapine levels in Middle Eastern patients: an observational study

BACKGROUND

Despite its superiority over other drugs for psychosis, clozapine remains underused and is associated with many clinical challenges, including difficulties in predicting therapeutic serum levels (350-600 ng/mL). We found no large or recent study that investigated the determinants of serum clozapine levels in Middle Eastern patients. Therefore, we investigated the association between clozapine dose and serum level, and the clinical predictors of the clozapine serum level, in Middle Eastern patients.

METHODS

This cross-sectional study included 94 patients of Middle Eastern ethnicity who attended the Clozapine Clinic in King Saud University Medical City in Riyadh, Saudi Arabia. We used a single measure of the serum clozapine level, which was collected 12 h after the last oral dose of clozapine under steady-state conditions.

RESULTS

The average clozapine dose and serum level were 400 mg/daily and 705 ng/mL, respectively. The majority of patients (59.8%) had serum levels higher than 600 ng/mL. Clozapine dose and serum level were positively correlated (r_s [94] = 0.32, p = 0.002). We generated a predictive model of the serum clozapine level, which revealed that the daily dose, smoking status, use of fluvoxamine or lamotrigine, and body mass index (BMI) predicted 43.6% of the variance in the serum level (p < 0.001). Using this model, we calculated that patients with a BMI of 25 kg/m² would require a clozapine dose between 50 to 275 mg/daily if they were non-smokers, and a dose of 200 to 450 mg/daily if they were smokers, in order to reach a serum clozapine level between 350 to 600 ng/mL. Patients with higher BMI and those receiving fluvoxamine would require lower doses.

CONCLUSIONS

This was a naturalistic study of the clozapine dose-level relationship and the clinical predictors of the serum clozapine level in a sample of Middle Eastern patients. The ratios of clozapine level to dose in our patients more closely resembled those reported in Asian samples than in European samples. These findings do not reduce the value of individualised therapeutic drug monitoring, but may assist clinicians when prescribing clozapine to Middle Eastern patients. Further psychopharmacological studies are needed on this demographic population.

First Use of Clozapine Point of Care Testing in Acute Inpatient Psychiatry: Preliminary Report

Clozapine is the antipsychotic of choice in treatment-resistant schizophrenia. Serum clozapine concentration testing is essential to monitor adherence, adjust dosing, and ensure treatment safety. However, patients who are acutely unwell are frequently reluctant to undergo blood testing requiring venipuncture. Also, conventional laboratory-based measurement of clozapine plasma levels can take days, thus contributing to the suboptimal use of clozapine when it is most needed. We pioneered clozapine whole-blood point of care (POC) testing in the acute inpatient setting in the treatment of a group of actively psychotic patients receiving clozapine during the outbreak of the COVID-19 pandemic. POC clozapine testing using automated homogenous immunoassay requires only finger prick blood sampling and is more acceptable to patients. As it produces results in minutes, clozapine POC testing serves to promptly ascertain adherence with treatment and inform therapeutic dosing. POC testing offered a more practical, less invasive, and quicker alternative to conventional methods of monitoring clozapine levels. Near immediate availability of clozapine levels expedited clinical decisions and helped ensure safe clozapine prescribing to our severely psychotic patients in a time of crisis. By facilitating patients' early safe discharge from the hospital, clozapine POC testing also reduced length of hospitalization.

Addressing the Needs of People with Schizophrenia in South Africa During the COVID-19 Pandemic

Research indicates that most people with Schizophrenia from low to middle-income countries do not receive adequate healthcare. Inadequate policies, lack of funding, poor service planning and neglect are some barriers to adequate care. Intrinsic barriers to care include stigma, lack of insight, and pathways to care that are often driven by cultural beliefs, and many systemic challenges. South Africa was not spared from the scourge of COVID-19, hosting a third of all reported cases in Africa. In a country with disparities, it would be of interest to get insight into the situation concerning the healthcare needs of people with Schizophrenia during the pandemic. A pandemic such as COVID-19 placed enormous strains on already limited and unequally distributed health care resources. In this paper, we discuss: (1) The South African healthcare system (with respect to Schizophrenia care). (2) COVID-19 policies related to the care of people with Schizophrenia (testing, access to vaccine). (3) Managing people with Schizophrenia amid the COVID-19 pandemic. (4) Recommendations.

Diagnostic error regarding the cause of cytopenia when increasing psychotropic drugs: Two case reports

Several psychotropic drugs can cause cytopenia, especially after increasing dosages or initiating treatment. However, cytopenia in patients with psychiatric disorders can also be due to other conditions such as leukemia. In this report, we discuss two cases of cytopenia that occurred during the adjustment of psychotropic medications in patients with severe psychiatric illness. The initial diagnosis in each case was drug-induced cytopenia; however, later, the cause of cytopenia was found to be acute promyelocytic leukemia. When cytopenia is observed while increasing the dosage of psychotropic drugs, suspicious drugs should be discontinued, though the possibility that cytopenia could be due to other reasons should be considered. If there are no signs of recovering blood cells or if cytopenia is severe, psychiatrists should consult hematologists promptly.

Implementation of a web-based computerised decision support system for Community Mental Health Services using national electronic health records (Preprint)

Background

A high proportion of patients with severe mental illness relapse due to nonadherence to psychotropic medication. In this paper, we use the normalization process theory (NPT) to describe the implementation of a web-based clinical decision support system (CDSS) for Community Mental Health Services (CMHS) called Actionable Intime Insights or AI². AI² has two distinct functions: (1) it provides an overview of medication and treatment history to assist in reviewing patient adherence and (2) gives alerts indicating nonadherence to support early intervention.

Objective

Our objective is to evaluate the pilot implementation of the AI² application to better understand the challenges of implementing a web-based CDSS to support medication adherence and early intervention in CMHS.

Methods

The NPT and participatory action framework were used to both explore and support implementation. Qualitative data were collected over the course of the 14-month implementation, in which researchers were active participants. Data were analyzed and coded using the NPT framework. Qualitative data included discussions, meetings, and work products, including emails and documents.

Results

This study explores the barriers and enablers of implementing a CDSS to support early intervention within CMHS using Medicare data from Australia’s national electronic record system, My Health Record (MyHR). The implementation was a series of ongoing negotiations, which resulted in a staged implementation with compromises on both sides. Clinicians were initially hesitant about using a CDSS based on MyHR data and expressed concerns about the changes to their work practice required to support early intervention. Substantial workarounds were required to move the implementation forward. This pilot implementation allowed us to better understand the challenges of implementation and the resources and support required to implement and sustain a model of care based on automated alerts to support early intervention.

Conclusions

The use of decision support based on electronic health records is growing, and while implementation is challenging, the potential benefits of early intervention to prevent relapse and hospitalization and ensure increased efficiency of the health care system are worth pursuing.

A Comprehensive Monitoring of Clozapine and Related Components in Clinical Practices. Saudi Arabian Scenario

OBJECTIVES

Clozapine is considered as effective medication for treatment resistant schizophrenia. Due to its potential severe adverse effects' clozapine is underused in the clinical settings. Information's on clinical use and monitoring of clozapine is lacking in middle east. This research analysis clozapine prescription and monitoring patterns a in a university teaching hospital in Saudi Arabia.

EXPERIMENTAL DESIGN

A retrospective observational study was conducted in the psychiatric department of a university hospital in Saudi Arabia. Patients on treatment with clozapine for minimum one year were reviewed and assessed for clozapine mandatory and non-mandatory requirements and its correlated factors.

OBSERVATION

Majority of patients were male [(n = 36) 63%] and the average age of was 36.8 ± 12.3. TRS schizophrenia[(n = 49),85%] was the common indications. Prior to initiation of clozapine all recommended guidelines was followed for all patients (100%). In addition to the blood monitoring and vitals LFT (80.75%) and weight (87.77%) were frequently measured. Hematological work up performed routinely throughout initial 18 weeks (71.9 %) and every month (59.6%). Weight gain (29.8%) was the most documented adverse effects.

CONCLUSION

The current study explored experiences with clozapine prescribing practices in a university hospital KSA and suggest that clozapine prescription is completely adhered with already existing guidelines in terms of dosing and monitoring. There exist a careful balance of benefit and risk in term of adverse reaction of clozapine in the local population.

Reduction in Absolute Neutrophil Counts in Patient on Clozapine Infected with COVID-19

Despite its severe adverse effects, such as agranulocytosis, clozapine is the primary treatment for treatment-resistant schizophrenia. The established clozapine monitoring system has contributed to reducing agranulocytosis incidence and mortality rates. However, the pandemic coronavirus disease 2019 (COVID-19) has caused changes in the monitoring system. This review aimed to assess the current evidence on the neutrophil changes in the patient on clozapine treatment and infected with COVID-19. Individual cases reported various absolute neutrophil count (ANC) levels, normal, reduced, or elevated. No agranulocytosis case was reported. One case had a borderline moderate-severe ANC level, but the patient was in the 18-week period of clozapine treatment. A cumulative analysis of case the series initially reported inconclusive results. However, a more recent study with a larger sample size reported a significant reduction in the ANC during COVID-19 infection. Nevertheless, this effect is transient as no significant difference was found between the baseline and the post-infection period in ANC levels. In conclusion, COVID-19 is associated with a temporary reduction in ANC levels. The results supported the recommendation to reduce the frequency of clozapine monitoring in the eligible candidates. However, more data are required to confirm the current findings given the limitations, including study design, sample size, and statistical analysis.

Rapid-onset clozapine-induced hyperglycaemia: pathways of glycaemic dysregulation

Clozapine is an atypical antipsychotic used in refractory schizophrenia, also efficient in alleviating dyskinesia in Parkinson's disease. Despite its potency, this drug is associated with severe metabolic side effects, including increased risk for diabetes. We report the case of a 45-year-old overweight woman with Parkinson's disease who presented with rapid-onset hyperglycaemia within 2 months after starting clozapine for refractory dyskinaesia. She had a history of gestational diabetes. At presentation, her blood glucose level was 505 mg/dL and glycated haemoglobin 12.4%, with no catabolic symptoms. Clozapine was suspended and metformin was started, but adequate glycaemic control was achieved only with insulin therapy, along with exenatide and empagliflozin afterwards. We assume that clozapine acted as a trigger for rapid deterioration of glycaemic control through direct pathophysiological mechanisms, rather than an indirect slowly evolving weight gain-related metabolic syndrome pathway. Clinicians should be aware of this complication, enabling timely diagnosis and proper treatment.

Considerations of HLA, Renal Failure, Valproic Acid Use, and Current Treatment Guidelines in Clozapine-Induced Agranulocytosis

Clozapine, the choice atypical antipsychotic for refractory schizophrenia, schizoaffective disorder, and bipolar disorder, has been shown to reduce positive and negative symptoms of schizophrenia. Clozapine, though beneficial in reducing the need for hospitalization, rehabilitation, and health care costs, is known as a drug of last resort due to its potential adverse event of clozapine-induced agranulocytosis, which holds a case fatality rate between 4.2 and 16%. Herein, we describe a female patient with longstanding schizoaffective disorder and chronic kidney disease who suffered from clozapine-induced agranulocytosis after failing two other atypical antipsychotics. Retrospective considerations of this case and management highlight risk factors such as HLA status, renal failure, and concurrent valproic acid use which presently do not have official screening, guidelines, or restrictions in place when prescribing clozapine. Additionally, there are no specific clozapine-induced agranulocytosis management recommendations such as G-CSF/filgrastim dose, timing of bone marrow aspirate and biopsy, and use of concomitant valproate. We propose that further comprehensive official screening, monitoring, and guidelines in the prescribing of clozapine, and further guidelines in the treatment of clozapine induced agranulocytosis, could increase the cost-effectiveness of clozapine treatment, and decrease the incidence, and morbidity of this feared adverse event.

Mental Health Nurses' Knowledge of Clozapine

Clozapine, sold under the brand name Clozaril, is an antipsychotic medication prescribed since the 1970s as an effective treatment for individuals with treatment resistive schizophrenia. Medical experts have produced extensive literature on the need for close monitoring as this medication can cause life threatening adverse effects. Mental health nurses play a vital role in the management of clozapine, however to date just one study specifically examines psychiatric/mental health nurse's knowledge of this medication. Nurses need to be aware of the adverse effects and be able to provide psychoeducation to help support and inform clients prescribed this medication. This study used a survey questionnaire. A clozapine knowledge questionnaire with 18 questions was developed by De Hert et al. to explore psychiatric/mental health nurse's knowledge on the adverse effects of clozapine. We distributed a shortened version of this knowledge questionnaire (12-multi-choice questions) to 209 mental health nurses working within one Irish Mental Health Service. One hundred and twenty-nine (n = 129) nurses completed the questionnaire with a response rate of 62%. Our results indicated that over 40% of mental nurses had not received sufficient education on clozapine medication during their formal education. We found that just 50% of participants scored over six correct questions out of 12 questions on various areas of knowledge related to clozapine medication. We identified gaps in knowledge on clozapine medication in relation to on myocarditis, epilepsy and metabolic syndrome. We highlighted gaps in mental health nurses' knowledge of clozapine medication that need to be improved in order to help clients. We advocate additional education on clozapine medication at undergraduate education and through educational packages at the service level.

Clozapine intoxication with severe adverse effects induced by an inflammatory and infectious process: a case report

Background

Clozapine intoxication can be life-threatening. Outside of the common drug–drug interactions, tobacco smoking, and caffeine consumption, infectious and inflammatory processes are important contributors to clozapine intoxication. Although this relationship has been reported previously, the literature is scant of proper research articles describing the presentation and management of this unpredictable interaction. Therefore, clinicians need to rely heavily on case reports describing clozapine intoxication caused by inflammation and/or infection.

Case presentation

A 64-year-old Caucasian woman known for schizophrenia was brought to the emergency department (ED) with severe signs and symptoms of clozapine intoxication (general deterioration, drowsiness, neutropenia, and ileus). She was on clozapine 700 mg daily amongst other medications. The clozapine dose was stable for over 3 years, and there were no recent changes in her medications. The initial culprit was determined to be an infectious/inflammatory process of gastrointestinal origin with contribution from dehydration and constipation. Clozapine and norclozapine serum concentrations confirmed the intoxication: 1315 ng/mL and 653 ng/mL, respectively. She drastically improved with clozapine dose reduction and antibiotic therapy. She remained stable for years with clozapine 600 mg daily with stable clozapine serum levels.

Conclusion

This case report illustrates the possibility of severe toxicity associated with an acute infectious and/or inflammatory process in patients on clozapine therapy. Clinicians must maintain a high level of suspicion in patients taking clozapine who develop and an infectious and/or inflammatory process. Constipation secondary to clozapine intoxication can exacerbate the initial intoxication process.

The side effect profile of Clozapine in real world data of three large mental health hospitals

OBJECTIVE

Mining the data contained within Electronic Health Records (EHRs) can potentially generate a greater understanding of medication effects in the real world, complementing what we know from Randomised control trials (RCTs). We Propose a text mining approach to detect adverse events and medication episodes from the clinical text to enhance our understanding of adverse effects related to Clozapine, the most effective antipsychotic drug for the management of treatment-resistant schizophrenia, but underutilised due to concerns over its side effects.

MATERIAL AND METHODS

We used data from de-identified EHRs of three mental health trusts in the UK (>50 million documents, over 500,000 patients, 2835 of which were prescribed Clozapine). We explored the prevalence of 33 adverse effects by age, gender, ethnicity, smoking status and admission type three months before and after the patients started Clozapine treatment. Where possible, we compared the prevalence of adverse effects with those reported in the Side Effects Resource (SIDER).

RESULTS

Sedation, fatigue, agitation, dizziness, hypersalivation, weight gain, tachycardia, headache, constipation and confusion were amongst the highest recorded Clozapine adverse effect in the three months following the start of treatment. Higher percentages of all adverse effects were found in the first month of Clozapine therapy. Using a significance level of (p< 0.05) our chi-square tests show a significant association between most of the ADRs and smoking status and hospital admission, and some in gender, ethnicity and age groups in all trusts hospitals. Later we combined the data from the three trusts hospitals to estimate the average effect of ADRs in each monthly interval. In gender and ethnicity, the results show significant association in 7 out of 33 ADRs, smoking status shows significant association in 21 out of 33 ADRs and hospital admission shows the significant association in 30 out of 33 ADRs.

CONCLUSION

A better understanding of how drugs work in the real world can complement clinical trials.

Effect of a Housing Intervention on Selected Cardiovascular Risk Factors Among Homeless Adults With Mental Illness: 24-Month Follow-Up of a Randomized Controlled Trial

Background Cardiovascular disease is a leading cause of mortality among people experiencing homelessness. This study investigated whether housing intervention affects cardiovascular disease risk factors among homeless adults with mental illnesses over a 24-month period. Methods and Results We conducted a randomized controlled trial of a Housing First intervention that provided community-based scattered-site housing and support services. Five hundred seventy-five participants were randomized to the intervention (n=301) or treatment as usual (TAU) (n=274). Analyses were performed according to the intention-to-treat principle using generalized estimating equations. There were no differences in change over 24 months between the 2 groups for blood pressure, tobacco, and cocaine/crack use. However, the intervention had an impact on reducing the number of days of alcohol intoxication by 1.58 days compared with TAU (95% CI, -2.88 to -0.27, P=0.0018). Over the 24-month period, both the intervention and TAU groups had significant reductions in tobacco and cocaine use. Conclusions The intervention, compared with TAU, did not result in greater improvements in many of the selected cardiovascular risk factors. Since the study took place in a service-rich city with a range of pre-existing supportive services and universal health insurance, the high level of usual services available to the TAU group may have contributed to reductions in their cardiovascular disease risk factors. Further research is needed to develop interventions to reduce risk factors of cardiovascular disease among people experiencing homelessness and mental illness beyond existing treatments. REGISTRATION www.isrctn.comURL: www.isrctn.com. Unique Identifier: ISRCTN42520374.

Antipsychotic Polypharmacy

Physicians who treat patients with schizophrenia frequently encounter complex clinical situations not fully addressed by published treatment guidelines. Some of these situations lead to antipsychotic polypharmacy, often prescribed when clinical and social obstacles prevent access to clozapine and patients have had suboptimal responses to nonclozapine monotherapy. We offer our perspective on the place of antipsychotic polypharmacy in the current treatment guidelines for patients with schizophrenia. We summarize data on the prevalence of antipsychotic polypharmacy and describe common clinical situations in which this practice is encountered, along with the pharmacological underpinnings of this practice. We briefly review evidence on common risks of antipsychotic polypharmacy and describe the limited evidence for the possible benefits of such practice. Moreover, we take a look at alternative antipsychotic augmentation strategies that address all domains of psychosis.

The physical health and side-effect monitoring of patients prescribed clozapine: data from a clinical audit conducted in UK mental health services

BACKGROUND

In addition to mandatory haematological monitoring, treatment guidelines recommend routine monitoring of adverse effects and physical health in patients prescribed clozapine.

METHODS

NHS trusts/healthcare organisations participated in a clinical audit in the context of a UK quality improvement programme addressing clozapine-prescribing practice.

RESULTS

Data relating to 6948 adult patients prescribed clozapine were submitted by 63 NHS trusts/healthcare organisations. Of 481 patients treated with clozapine for up to 18 weeks, there was documented pretreatment screening of blood pressure, heart rate and ECG in at least 90%, and body weight, plasma lipids, plasma glucose/glycated haemoglobin (HbA1c) and physical examination in approximately 80%. During the first 2 weeks of clozapine treatment there was documented daily measurement of both heart rate and blood pressure in 82% and body temperature in 77%. In a subsample of 411 patients, of the 72% who had weekly side-effect assessments documented in the first month of treatment, a structured assessment tool had been used in 29%. Treatment monitoring up to 18 weeks included an ECG in 90%, C-reactive protein (CRP) or creatine kinase in 42%, and troponin or B-type natriuretic peptide (BNP) in 29%. In the 5908 patients prescribed clozapine for at least 1 year, blood pressure and body weight/body mass index were documented in at least 80%, plasma lipids in 78% and plasma glucose in 73%, with an ECG in 55%. Two-thirds were prescribed medication to manage side effects of clozapine and one third of those with a diagnosis of schizophrenia were prescribed a second antipsychotic medication.

CONCLUSION

The findings suggest that for most patients treated with clozapine in UK mental health services, physical health screening and side-effect monitoring follow recommended practice, but there was limited use of structured side-effect assessment tools. Monitoring for clozapine-induced myocarditis during the early risk period using markers of inflammation such as CRP, and cardiac damage such as troponin and BNP, was less consistent. This may partly reflect the variation in guideline recommendations for monitoring for myocarditis and partly the selected use of such tests when prompted by cardiac symptoms. The relatively common coprescription of medications for the majority of people on longer-term clozapine treatment may well further increase side-effect burden and physical health risks, reinforcing the need for continuing systematic monitoring.

Clozapine prescription pattern in patients with schizophrenia in Asia: The REAP survey (2016)

Clozapine is an effective antipsychotic medication for treatment resistant schizophrenia and is widely used in Asian countries. This study investigated clozapine prescription patterns and their associated factors in Asian countries and territories based on the database of the Research on Asian Psychotropic prescription study (REAP) conducted in 2016. Demographic and clinical information of 3744 schizophrenia patients in 15 Asian countries and territories was collected with a standardized data collection form. In total, 18.4% of the sample received clozapine, ranging from 2.6% in Japan to 32.3% in Hong Kong. Binary logistic regression analysis revealed that higher antipsychotic dose (OR = 1.002, P < 0.001), less frequent first admission in the sample (OR = 0.6, P < 0.001), more severe negative symptoms (OR = 1.4, P = 0.001) and less first generation antipsychotics (FGAs) (OR = 0.2, P < 0.001) were independently and significantly associated with clozapine prescription. Clozapine is frequently and increasingly prescribed for schizophrenia in Asia, with large variation across countries and territories. Given the diverse prescription patterns of clozapine found in Asian countries/territories, the clinical rationale of clozapine prescription needs careful consideration in Asia with more local input.

The relationship between serum clozapine concentrations and hematological parameters by a validated mass spectrometric method

OBJECTIVE

Clozapine is one of the most effective drugs for resistant schizophrenia, but its severe metabolic and hematological side effects limit the use of clozapine. It has been reported that clozapine blood concentrations should be maintained between 350-600 ng/mL. Our aim was to develop a determination method for clozapine and its main metabolites norclozapine and clozapine-N-oxide, to perform validation studies and to investigate the change of various biochemical parameters in patients using clozapine.

METHODS

A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated for clozapine measurement. Thus, blood samples were collected from 38 patients with schizophrenia and 32 healthy volunteers. Biochemical and hematological parameters were measured by Beckman-Coulter AU 5800 (Beckman Coulter, Brea, USA) and Beckman Coulter LH 780 analyzer (Beckman Coulter, Miami, FL, USA), respectively. Hormone levels were analyzed using Cobas 6000 analyzer (Roche Diagnostics, Germany).

RESULTS

The LCMS/MS method was linear between 1.22-2500 ng/mL (r² = 0.9971) for clozapine. The retention times of clozapine, norclozapine and clozapine-N-oxide were 0.92, 0.89 and 0.95, respectively. Blood glucose (GLU) (p = 0.025), low density lipoprotein (LDL-cholesterol) (p = 0.015), triglyseride (TG) (p = 0.042) and total cholesterol (TC) (p = 0.024) levels were higher; hemoglobin (HGB) (0.015), mean corpuscular hemoglobin (MCH) (0.036), red blood cell count (RBC) (0.020), neutrophil (NEU) (0.034), and platelet (PLT) (P = 0.005) levels were lower in the clozapine group.

CONCLUSIONS

This LC-MS/MS method was rapid, simple, cost-effective and suitable for the routine clozapine monitoring. Furthermore, norclozapine and clozapine-N-oxide were also determined. Monitoring of metabolic and hematological parameters with clozapine levels is very important. However, the limitations of the study were that the method was not validated for norclozapine and clozapine-N-oxide, so the validation parameters were not evaluated for these two metabolites.

Implementing a clozapine supply service in Australian community pharmacies: barriers and facilitators

BACKGROUND

Clozapine is the most effective antipsychotic for treatment-resistant schizophrenia, although serious adverse effects such as agranulocytosis and cardiomyopathy limit its use. In July 2015, Australian regulations changed to allow community-based prescribing and supply of clozapine for maintenance therapy. However, there is currently no information on the rate of clozapine services available in Australian community pharmacies, or the factors that influence a pharmacist's decision to provide, or not provide, a clozapine service, particularly from the perspective of those pharmacists who do not offer this service. This study investigated Australian community pharmacies providing a clozapine supply service and the barriers to, and facilitators of, implementing this service.

METHODS

This mixed method exploratory study was conducted in two stages: (1) a brief online survey of community pharmacists Australia-wide; and (2) semi-structured telephone interviews. The survey was conducted between November 2017-January 2018; results were analysed via descriptive statistics. Survey respondents who did not provide a clozapine service were eligible to participate in a telephone interview exploring barriers and facilitators. Interviews were undertaken between December 2017-January 2018 and data analysed thematically.

RESULTS

A total of 265 pharmacists completed the survey; 51.3% (n = 136) provided a clozapine service. Consumer demand was a key facilitator (n = 18/247; 66.1%) and the main barrier to implementing a clozapine service was a perceived lack of need (n = 70/122; 57.4%). Twelve survey respondents were interviewed; while most participants acknowledged that supplying clozapine in community pharmacies would benefit consumers due to convenience, the lack of training and support led to difficulties in service implementation.

CONCLUSIONS

Although regulatory changes aimed to improve access to clozapine, it is unclear if they have been successful, or to what degree. Community pharmacists were positive about supplying clozapine in the community but identified a need for training and support to raise awareness of the service so that eligible clozapine consumers can be transitioned to community-based care. Further research is needed about the perceptions of clozapine consumers to determine whether the regulatory changes have resulted in positive outcomes for their independence and quality of life.

A Chitosan-Carbon Nanotube-Modified Microelectrode for In Situ Detection of Blood Levels of the Antipsychotic Clozapine in a Finger-Pricked Sample Volume

The antipsychotic clozapine is the most effective medication available for schizophrenia and it is the only antipsychotic with a known efficacious clinical range. However, it is dramatically underutilized due to the inability to test clozapine blood levels in finger-pricked patients' samples. This prevents obtaining immediate blood levels information, resulting in suboptimal treatment. The development of an electrochemical microsensor is presented, which enables, for the first time, clozapine detection in microliters volume whole blood. The sensor is based on a microelectrode modified with micrometer-thick biopolymer chitosan encapsulating carbon nanotubes. The developed sensor detects clozapine oxidation current, in the presence of other electroactive species in the blood, which generate overlapping electrochemical signals. Clozapine detection, characterized in whole blood from healthy volunteers, displays a sensitivity of 32 ± 3.0 µA cm^-2 µmol^-1 L and a limit-of-detection of 0.5 ± 0.03 µmol L^-1 . Finally, the developed sensor displays a reproducible electrochemical signal (0.6% relative standard deviation) and high storage stability (9.8% relative standard deviation after 8 days) in serum samples and high repeatability (9% relative standard deviation for the 5th repetition) in whole blood samples. By enabling the rapid and minimally invasive clozapine detection at the point-of-care, an optimal schizophrenia treatment is provided.

When clozapine appears at a dance event…

Objectives: The content of substances sold and consumed as party drugs is often unknown. They may contain inactive, contaminated or unexpected ingredients, and the dosage of the active components may vary considerably. Obviously, these phenomena increase the chances of a wrong or delayed therapy. To illustrate this point, we report 3 cases of clozapine intoxication at a dance event where most likely clozapine tablets were sold as party drugs.Methods: The three cases were part of a prospective toxicology study at a nocturnal indoor dance event.Results: One patient had to be intubated after obstructive breathing with desaturation and bradycardia, while the 2 other patients presented with syncope and altered mental status. All patients recovered after 20 minutes to 8 hours. Systematic toxicological analysis of the blood samples revealed the presence of clozapine (73-244 ng/ml) and its metabolite norclozapine (9-59 ng/ml). A pill, found in a pocket of one patient, was identified as Leponex® 100 mg (clozapine). This neuroleptic drug is mainly prescribed for treatment-resistant schizophrenia. In clozapine-naive subjects, orthostatic hypotension, bradycardia and syncope have been reported with a single 25 mg oral dose. Serum clozapine concentrations of the 3 cases were below the defined therapeutic range (350-600ng/ml) and the clozapine:norclozapine ratios were suggestive for recent drug intake.Conclusion: Routine drug screening may be unable to detect the toxic agent(s) involved. Whenever unusual symptoms are observed in an intoxicated patient, blood and urine samples should be sent to a reference toxicology laboratory.

Acute onset clozapine-induced hyperglycaemia: A case report

Clozapine is an atypical antipsychotic which is described to have higher efficacy among all available antipsychotic medications. Clozapine is reserved especially for resistant schizophrenia due to its side effects. Clozapine-induced metabolic syndrome and hyperglycaemia are common long-term side effects and are responsible for increased mortality in patients with schizophrenia. In this case, a patient with resistant schizophrenia was presented with acute-onset hyperglycaemia and delirium with the use of clozapine within a week. Withdrawal of clozapine in the patient led to the improvement in delirium and hyperglycaemia without the use of any hypoglycaemic agent. This case supports the notion that in certain cases clozapine can induce hyperglycemia through possible direct pathophysiological mechanisms within a shorter time frame.

Clozapine-induced agranulocytosis and leukopenia: Incidence, associated factors, and rate of hematologic adverse-effects monitoring in psychiatric out-patient services in Thailand

The present study aimed to investigate the incidence of agranulocytosis and leukopenia and its associated factors in Thai schizophrenia patients treated with clozapine and the rate of hematologic adverse events monitored in clinical practice. Data were collected from the medical records of 641 outpatients at two hospitals. The results showed no cases of agranulocytosis and 20 cases of leukopenia (3.1%), 85% of which were observed after 1 year of prescription. The associated factors were female (p = 0.019) and duration of clozapine prescription (p = 0.026). According to the guideline for safety monitoring, 23.6% of cases had neutrophils count monitoring.

A utilização do Método de Rorschach no diagnóstico diferencial da Esquizofrenia e Transtorno Dissociativo de Identidade

RESUMO O objetivo deste artigo foi investigar a prevalência do Transtorno Dissociativo de Identidade (TDI) em dez pacientes diagnosticados com esquizofrenia com característica paranóide, com base no Método de Rorschach. Foram registrados indicadores ou sintomas psicológicos que caracterizaram o diagnóstico diferencial desses pacientes, analisadas diferenças clínicas específicas e verificado o enquadramento dos dados obtidos, com a aplicação da Técnica de Rorschach. Para fins de diagnóstico diferencial, observou-se que dois pacientes apresentaram sintomas diferenciais aos da esquizofrenia, sendo que um deles apresentou sintomas dissociativos, não sendo confirmada a prevalência do TDI entre os esquizofrênicos. No caso da esquizofrenia e do TDI, devido às características similares que apresentam, avaliações multidisciplinares são indicadas para se fazer o diagnóstico diferencial entre eles.

Predicting Unsuccessful Clozapine Treatment After First Use in Adult Patients With Psychotic Disorders

PURPOSE/BACKGROUND

Cessation of clozapine therapy and insufficient response may result in relapse of psychotic symptoms and in clinical admissions. However, discontinuation rates are high. Identifying patients at risk for unsuccessful clozapine use might enable clinicians to direct specific attention to them.

METHODS/PROCEDURES

Routinely collected data from a large insurance company were used to develop a simple prediction model for unsuccessful clozapine treatment in psychiatric patients 1 year after clozapine was first dispensed by a community pharmacy in the Netherlands. Multivariate logistic regression analyses were performed with the Nagelkerke R statistic as a measure of the predictive value of the model.

FINDINGS/RESULTS

A total of 937 patients were dispensed clozapine for the first time by their community pharmacy between January 1, 2011, and December 31, 2015 (index date). Of these, 741 patients had started their clozapine treatment in hospital before the index date (inpatient starters); the remaining 196 patients started clozapine as outpatients on the index date (outpatient starters). In 191 patients (20.4%), clozapine treatment was unsuccessful 1 year after the index date. Unsuccessful treatment was more common among outpatient starters than among inpatient starters (32.1% vs 17.3%). Using backward selection of the variables, a model consisting of 61 variables had the best predictive value overall (Nagelkerke R = 0.301), whereas a model consisting of 52 variables had the best predictive value in outpatient starters (Nagelkerke R = 0.676).

IMPLICATIONS/CONCLUSIONS

The likelihood of unsuccessful clozapine treatment after 1 year was higher among patients who started clozapine as outpatients. Despite the use of a diversity of variables and different statistical approaches, it was not possible to make a simple prediction model for unsuccessful clozapine treatment using relatively easily accessible data.

Antipsychotic prescribing patterns on admission to and at discharge from a tertiary care program for treatment-resistant psychosis

Retrospective data were collected from 330 individuals who were treated at a tertiary care program for treatment-resistant psychosis between 1994 and 2010. The main objectives were to compare the use of antipsychotic monotherapy to polypharmacy and to characterize within-individual changes in treatment and symptomatology between admission and discharge. At admission, individuals who were prescribed only one antipsychotic were comparable to those who were prescribed at least two antipsychotics with regard to demographics and symptom severity. The use of psychotropic medications other than antipsychotics was also similar between the two groups. However, the magnitude of antipsychotic utilization was greater in individuals who were receiving antipsychotic polypharmacy. In addition, a greater proportion received excessive doses at admission. Similar findings were observed when the two antipsychotic prescribing practices were compared at discharge. Three important patterns were identified when investigating within-individual changes. First, fewer individuals were prescribed more than one antipsychotic at discharge. This was accompanied by a general decrease in the magnitude of antipsychotic utilization. Second, the number of individuals who were prescribed clozapine had increased by discharge. Most who were already prescribed clozapine at admission had their doses increased. Third, improvements in symptomatology were observed across all of the subscales included in the Positive and Negative Symptom Scale (PANSS); 57.9% of individuals experienced a relative reduction in total PANSS scores exceeding 20%. Based on these findings, it is possible to alleviate symptom severity while reducing antipsychotic utilization when patients are treated at a tertiary care program for treatment-resistant psychosis.

Clozapine-Induced Cardiovascular Side Effects and Autonomic Dysfunction: A Systematic Review

Background: Clozapine is the antipsychotic of choice for treatment-resistant schizophrenia and has minimal risk for extrapyramidal symptoms. Therapeutic benefits, however, are accompanied by a myriad of cardiometabolic side-effects. The specific reasons for clozapine's high propensity to cause adverse cardiometabolic events remain unknown, but it is believed that autonomic dysfunction may play a role in many of these.

Objective: This systematic review summarizes the literature on autonomic dysfunction and related cardiovascular side effects associated with clozapine treatment.

Method: A search of the EMBASE, MEDLINE, and EBM Cochrane databases was conducted using the search terms antipsychotic agents, antipsychotic drug^*, antipsychotic^*, schizophrenia, schizophren^*, psychos^*, psychotic^*, mental ill^*, mental disorder^*, neuroleptic^*, cardiovascular^*, cardiovascular diseases, clozapine^*, clozaril^*, autonomic^*, sympathetic^*, catecholamine^*, norepinephrine, noradrenaline, epinephrine, adrenaline.

Results: The search yielded 37 studies that were reviewed, of which only 16 studies have used interventions to manage cardiovascular side effects. Side effects reported in the studies include myocarditis, orthostatic hypotension and tachycardia. These were attributed to sympathetic hyperactivity, decreased vagal contribution, blockade of cholinergic and adrenergic receptors, reduced heart rate variability and elevated catecholamines with clozapine use. Autonomic neuropathy was identified by monitoring blood pressure and heart rate changes in response to stimuli and by spectral analysis of heart rate variability. Metoprolol, lorazepam, atenolol, propranolol, amlodipine, vasopressin and norepinephrine infusion were used to treat tachycardia and fluctuations in blood pressure, yet results were limited to case reports.

Conclusion: The results indicate there is a lack of clinical studies investigating autonomic dysfunction and a limited use of interventions to manage cardiovascular side effects associated with clozapine. As there is often no alternative treatment for refractory schizophrenia, the current review highlights the need for better designed studies, use of autonomic tests for prevention of cardiovascular disease and development of novel interventions for clozapine-induced side effects.

Clozapine use in geriatric patients- Challenges

Clozapine is the first second generation antipsychotic with different receptor profile of action. Clozapine is the most efficacious drug for the treatment of psychotic disorder and is the drug of choice in treatment resistant schizophrenia. Clozapine is used in elderly patients infrequently owing to its adverse effects profile and tolerability. There is paucity of literature with respect to clozapine use in late life. In this narrative review, we discuss clozapine use in elderly and challenges associated with its use.

Low-dose Clozapine-induced Seizure: A Case Report

Seizures are believed to be a dose-dependent side effect of clozapine. In this case report, we describe a patient who had tonic-clonic seizures after using a low dose clozapine who did not have any seizure risk. The 29-year-old male patient had been followed-up with a diagnosis of schizophrenia for about 5 years. When using clozapine 200 mg/day he had a tonic-clonic seizure with bilateral diffuse epileptic activity in electroencephalography (EEG). In the literature, there are a few case reports about low-dose clozapine-induced seizure. Seizures were observed in our case with a low dose of clozapine (200 mg/day) making this case remarkable. EEG monitoring at regular intervals and examination of plasma levels of clozapine could be useful in preventing the development of seizures.