Clozapine and incidence of myocarditis and sudden death - Long term Australian experience

The cardiovascular toxicity of clozapine in embryonic zebrafish and RNA sequencing-based transcriptome analysis

Clozapine (CLZ) is the most prescribed medication for treating refractory schizophrenia but is associated with significant cardiovascular toxicity. This study aimed to investigate the cardiovascular toxicity induced by CLZ using zebrafish as a model animal. For this purpose, zebrafish developed to 80-h post-fertilization were exposed to different CLZ concentration solutions for 24 h followed by cardiac morphological observations in yolk sac edema, pericardial edema, and blood coagulation, in addition to increased SV-BA distance, functionally manifested as bradycardia, and decreased cardiac ejection fraction using the untreated embryos as control. At the same time, RNA sequencing was used to study the possible molecular mechanism of CLZ-induced cardiovascular toxicity. The results indicated that compared to the control group, the experimental groups possessed a total of 5888 differentially expressed genes (DEGs), where gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) functional enrichment of analysis indicated that DEGs were mainly enriched in the pathways related to ion channels. These findings may provide new insights and directions for the subsequent in-depth study of the molecular mechanism of CLZ-induced cardiovascular toxicity.

Antipsychotics and Risks of Cardiovascular and Cerebrovascular Diseases and Mortality in Dwelling Community Older Adults

This study aims to investigate the effect of antipsychotic agents on cardiovascular and cerebrovascular diseases (CVD/CEV) and mortality risks in the older population living in a community. A cohort of 42,650 new users of antipsychotic agents was built using Quebec healthcare databases (1998-2011). The outcomes were CVD/CEV and mortality incidence in 5 years of follow-up in the total cohort, sub-cohort of patients with no schizophrenia/dementia, sub-cohort with schizophrenia, and sub-cohort with dementia. Comparisons were made between the new users who continued the treatment (adherent level ≥ 60%) vs. those ceasing treatment (adherence level < 60%) using inverse probability of treatment weighting and Cox models. Comparing high adherence vs. low levels, CVD/CEV risk was increased by 36% in the sub-cohort with schizophrenia for atypical antipsychotic users and by 25% in the sub-cohort with dementia for typical antipsychotic users. An increasing mortality risk of 2- to 3-fold was linked with the typical antipsychotic use in all cohorts except the sub-cohort with schizophrenia; in addition, mortality risk is linked with the use of high vs. low doses. Antipsychotics were not linked with CVD/CEV risk, except for atypical antipsychotics in patients with schizophrenia and typical antipsychotics in patients with dementia. The mortality risk was linked with the use of typical antipsychotics and the dose used.

Sudden Cardiac Death in People With Schizophrenia: Higher Risk, Poorer Resuscitation Profiles, and Differing Pathologies

BACKGROUND

People with schizophrenia account for approximately 1.0% of the population and seem to experience increased rates of sudden cardiac death (SCD).

OBJECTIVES

This study sought to determine characteristics of increased SCD in people with schizophrenia.

METHODS

The End Unexplained Cardiac Death (EndUCD) prospective state-wide registry compared people aged 15 to 50 years with and without schizophrenia who experienced SCD within a 2-year time period and were referred for forensic evaluation.

RESULTS

We identified 579 individuals, of whom 65 (11.2%) had schizophrenia. Patients with schizophrenia were more commonly smokers (46.2% vs 23.0%; P < 0.0001), consumed excess alcohol (32.3% vs 21.4%; P = 0.05), and used QTc-prolonging medications (69.2% vs 17.9%; P < 0.0001). They were less likely to arrest while exercising (0.0% vs 6.4%; P = 0.04). Unfavorable arrest-related factors included lower rates of witnessed arrest (6.2% vs 23.5%; P < 0.0001), more likely to be found in asystole (92.3% vs 73.3%; P < 0.0001), and being more likely to be found as part of a welfare check after a prolonged period of time (median 42 hours vs 12 hours; P = 0.003). There was more frequent evidence of decomposition, and they more commonly underwent autopsy (41.2% vs 26.4%; P = 0.04 and 93.8% vs 82.5%; P = 0.05), with a diagnosis of nonischemic cardiomyopathy being more common (29.2% vs 18.1%; P = 0.04).

CONCLUSIONS

People with schizophrenia account for 11% of young SCD patients referred for forensic investigations, exceeding population rates by 11-fold. They have a higher preexisting cardiac risk factor burden, unfavorable resuscitation profiles, and higher rates of nonischemic cardiomyopathy. Strategies targeting biopsychosocial support may deliver not only psychological benefits, but also help to decrease unwitnessed cardiac arrest.

The association between exposure to clozapine, olanzapine, and quetiapine and the outcomes perimyocarditis and heart failure: A population-based cohort study

The risk of cardiac adverse events following clozapine use is debated and is unknown for the chemically related and widely used antipsychotics olanzapine and quetiapine. National Swedish registers were used to identify all patients 16-75 years old with antipsychotic dispensations between 2005 and 2018. The short-term outcome was a diagnosis of perimyocarditis (pericarditis and/or myocarditis) within two months of first dispensation, and the long-term outcome was heart failure (including cardiomyopathy) within three years. Cox regressions with time varying exposure were used to estimate hazard rates (HR) and their 95% confidence intervals (CI). A total of 201,045 individuals were included in the cohort. The risk of developing perimyocarditis during clozapine treatment tripled compared to no antipsychotic treatment (HR 3.4, CI 1.6-7.3), although the absolute rate remained comparably low. The long-term risk of heart failure during clozapine treatment was also elevated (HR 1.3, CI 1.1-1.7). Treatment with either or both olanzapine or quetiapine was not associated with an increased relative risk of perimyocarditis, or heart failure compared to no antipsychotic treatment. Clozapine use is therefore associated with a substantially elevated short-term risk of perimyocarditis and an increased risk of heart failure within three years.

Myocarditis in patients on long-term antipsychotics -mechanism, management and recent updates

Objective

Clozapine is the first atypical antipsychotic drug and was frequently cited as the most effective antipsychotic for treatment-resistant schizophrenia, but it is associated with a concert of significant cardiotoxic side effects. Clozapine-induced Myocarditis (CIM) is diagnosed based on the combination of clinical symptoms, laboratory investigations, radiological findings, and sometimes biopsy. The literature on CIM management and clinical consensus on the best course of action is mixed.

Methodology

An all-language literature search on Medline, Cochrane, Embase, and Google Scholar until April 2022. The following search strings and Medical Subject Heading (MeSH) terms were used: "CIM," "clozapine," "cardiotoxicity," and "myocarditis." We explored the literature on CIM for its pathophysiology, diagnosis, monitoring, and management.

Results

The clinical features of CIM may be highly variable, ranging from asymptomatic disease to fulminant heart failure, and cessation of medication was the mainstay treatment of CIM, followed by supportive therapy. Other antipsychotics have also been linked with cardiotoxic side effects.

Conclusion

Despite being the most effective antipsychotic, clozapine is associated with a cardiotoxic side effect. Current literature suggests that these antipsychotic-related cardiotoxic events impact the treatment selection for schizophrenia and other psychotic disorders, and they must be kept in mind while designing new treatment protocols in the future.

Clozapine-induced Myocarditis: Pathophysiologic Mechanisms and Implications for Therapeutic Approaches

Clozapine, a superior treatment for treatment-resistant schizophrenia can cause potentially life-threatening myocarditis and dilated cardiomyopathy. While the occurrence of this condition is well known, its molecular mechanisms are unclear and may be multifactorial. Putative mechanisms warrant an in-depth review not only from the perspective of toxicity but also for understanding the molecular mechanisms of the adverse cardiac effects of clozapine and the development of novel therapeutic approaches. Clozapine-induced cardiac toxicity encompasses a diverse set of pathways, including (i) immune modulation and proinflammatory processes encompassing an IgEmediated (type I hypersensitivity) response and perhaps a cytokine release syndrome (ii) catecholaminergic activation (iii) induction of free radicals and oxidative stress (iv) activation of cardiomyocyte cell death pathways, including apoptosis, ischemia through impairment in coronary blood flow via changes in endothelial production of NO and vasoconstriction induced by norepinephrine as well as other factors released from cardiac mast cells. (v) In addition, an extensive examination of the effects of clozapine on non-cardiac cellular proteins demonstrates that clozapine can impair enzymes involved in cellular metabolism, such as pyruvate kinase, mitochondrial malate dehydrogenase, and other proteins, including α-enolase, triosephosphate isomerase and cofilin, which might explain clozapine-induced reductions in myocardial energy generation for cell viability as well as contractile function. Pharmacologic antagonism of these cellular protein effects may lead to the development of strategies to antagonize the cardiac damage induced by clozapine.

Protective effects of salavianolic acid A on clozapine-induced cardiotoxicity in zebrafish

The clinical use of clozapine (CLZ), an atypical antipsychotic drug, was affected by side effects, such as cardiotoxicity. We selected normally-developing zebrafish embryos to explore the antagonism of salvianolic acid A (SAA) against clozapine-induced cardiotoxicity. Embryos were treated with CLZ and SAA, and zebrafish phenotypes were observed at 24 h, 48 h, 72 h, and 96 h after treatment. The observed phenotypes included heart shape, heart rate, and venous sinus-arterial bulb (SV-BA) interval. Real-time quantitative PCR was used to detect changes in the expression of genes involved in heart inflammation, oxidative stress and apoptosis. The results showed that SAA relieved pericardial edema, increased heart rate, and reduced the SV-BA interval. The PCR results also showed that when the zebrafish embryos were incubated with SAA and CLZ for 96 h, the expression of il-1b and nfkb2 were significantly down-regulated, the expression of sod1 and cat were significantly up-regulated, the expressions of mcl1a and mcl1b were significantly down-regulated. In summary, SAA can antagonized clozapine-induced cardiotoxicity.

Adverse Drug Reactions in Relation to Clozapine Plasma Levels: A Systematic Review

Clozapine is the gold standard for treatment-resistant schizophrenia. Serious and even life-threatening adverse effects, mostly granulocytopenia, myocarditis, and constipation, are of great clinical concern and constitute a barrier to prescribing clozapine, thus depriving many eligible patients of a lifesaving treatment option. Interestingly, clozapine presents variable pharmacokinetics affected by numerous parameters, leading to significant inter- and intra-individual variation. Therefore, therapeutic drug monitoring of plasma clozapine levels confers a significant benefit in everyday clinical practice by increasing the confidence of the prescribing doctor to the drug and the adherence of the patient to the treatment, mainly by ensuring effective treatment and limited dose-related side effects. In the present systematic review, we aimed at identifying how a full range of adverse effects relates to plasma clozapine levels, using the Jadad grading system for assessing the quality of the available clinical evidence. Our findings indicate that EEG slowing, obsessive-compulsive symptoms, heart rate variability, hyperinsulinemia, metabolic syndrome, and constipation correlate to plasma clozapine levels, whereas QTc, myocarditis, sudden death, leucopenia, neutropenia, sialorrhea, are rather unrelated. Rapid dose escalation at the initiation of treatment might contribute to the emergence of myocarditis, or leucopenia. Strategies for managing adverse effects are different in these conditions and are discussed accordingly.

Risk factors for clozapine-induced myocarditis and cardiomyopathy: A systematic review and meta-analysis

OBJECTIVE

Clozapine is the most effective medication for treatment-refractory schizophrenia, but it is associated with severe cardiac adverse events including myocarditis and cardiomyopathy. To aid treatment decision-making for clinicians, patients and their carers, we conducted a systematic review and meta-analysis to identify potential risk factors for clozapine-induced myocarditis and cardiomyopathy.

METHODS

A systematic search was conducted of PubMed, Embase, CINAHL, Web of Science, Cochrane and PsycInfo for studies reporting myocarditis and cardiomyopathy among people on clozapine and potential risk factors. We calculated pooled effect sizes on risk factors using a random-effects meta-analytic model. Risk of publication bias was assessed using the Newcastle-Ottawa scale.

RESULTS

Seven studies met the inclusion criteria, of which six studies had quantitative data included in the meta-analysis. The odds of clozapine-induced myocarditis increased with concurrent sodium valproate use (k = 6, n = 903, pooled OR 3.58, 95% CI 1.81-7.06), but were not significantly greater with the use of quetiapine, lithium or selective serotonin reuptake inhibitors. Our qualitative review identified conflicting results reported for increasing age and higher clozapine dose as risk factors for myocarditis. No other factors, including genetic risk, sex, ethnicity, smoking, alcohol, substance abuse or cardiometabolic disease, were associated with greater odds of myocarditis. No risk factors for cardiomyopathy were identified in the literature.

CONCLUSION

Concurrent use of sodium valproate increases the odds of clozapine-induced myocarditis. Thus, clinicians should consider the temporary cessation of sodium valproate during the initial titration phase of clozapine.

mTORC1 inhibitor effects on rapid ketamine-induced reductions in suicidal ideation in patients with treatment-resistant depression

Suicide is a public health crisis with limited treatment options. Ketamine has demonstrated rapid and robust improvements in suicidal ideation (SI). The parent study for the secondary pilot analyses presented here was a double-blind, cross-over trial that found pretreatment with the mechanistic target of rapamycin complex 1 (mTORC1) prolonged the antidepressant effects of ketamine. Here we examined the effect of mTORC1 inhibition on ketamine's antisuicidal effects. Twenty patients in a major depressive episode were randomized to pretreatment with oral rapamycin (6 mg) or placebo prior to IV ketamine (0.5 mg/kg). We found ketamine administration resulted in significant improvements across all measures with the largest effect at 24 h with only the Beck Scale for Suicide remaining significant at the two-week follow-up. There were no significant main effects of pretreatment. While these analyses are pilot in nature and overall severity of SI was relatively low, the antisuicidal findings (no effect of rapamycin) being in contrast to the antidepressant effects (prolonged effect with rapamycin), suggest the rapid-acting antisuicidal and antidepressant effects of ketamine may be mechanistically distinct and the trajectories of response, recovery, and relapse may be independent. These findings provide additional evidence of ketamine's antisuicidal effects and highlight the importance of future studies that continue to examine potential differences in mechanisms and trajectory of outcomes.

Transient Clozapine-induced Myocarditis Without Discontinuation of Medication: A Series of 2 Patients

BACKGROUND

Clozapine, an antipsychotic medication used to treat treatment-refractory schizophrenia, has been associated with various dangerous side effects, including myocarditis. However, there have been few published cases reporting on patients with clozapine-induced myocarditis confirmed by cardiac magnetic resonance imaging or the management, treatment, and follow-up of these patients.

METHODS

This report describes 2 cases of patients with treatment-refractory schizophrenia evidencing transient clozapine-induced myocarditis. Detailed information including laboratory values, imaging results, and clinical notes were gathered.

FINDINGS

The 2 cases demonstrated differing manifestations of clozapine-induced myocarditis. Both cases showed that such myocarditis can be transient and can be treated clinically with close observation without discontinuation of clozapine.

IMPLICATIONS

These cases show that clozapine-induced myocarditis is transient at times and can self-resolve without discontinuation of clozapine. These observations may suggest a change in clinical practice so that, with close observation, we can avoid risking psychiatric decompensation in select patients with a history of treatment-resistant schizophrenia.

Atypical antipsychotics and oxidative cardiotoxicity: review of literature and future perspectives to prevent sudden cardiac death

Oxidative stress is considered the principal mediator of myocardial injury under pathological conditions. It is well known that reactive oxygen (ROS) or nitrogen species (RNS) are involved in myocardial injury and repair at the same time and that cellular damage is generally due to an unbalance between generation and elimination of the free radicals due to an inadequate mechanism of antioxidant defense or to an increase in ROS and RNS. Major adverse cardiovascular events are often associated with drugs with associated findings such as fibrosis or inflammation of the myocardium. Despite efforts in the preclinical phase of the development of drugs, cardiotoxicity still remains a great concern. Cardiac toxicity due to second-generation antipsychotics (clozapine, olanzapine, quetiapine) has been observed in preclinical studies and described in patients affected with mental disorders. A role of oxidative stress has been hypothesized but more evidence is needed to confirm a causal relationship. A better knowledge of cardiotoxicity mechanisms should address in the future to establish the right dose and length of treatment without impacting the physical health of the patients.

Monitoring for myocarditis during treatment initiation with clozapine

OBJECTIVE

Clozapine use is associated with myocarditis. In this study, we investigated what clinical signs and symptoms, and/or laboratory test(s), alert clinicians to presumptive myocarditis (PrMy) most accurately and at the earliest time point. We also investigated the incidence of PrMy during the initial exposure to clozapine versus in patients restarted on clozapine after extended interruption of prior prolonged treatment.

METHODS

100 patients admitted to state psychiatric hospital started on clozapine were recruited into the study. 76 patients were treated with clozapine for the first time and 24 patients were restarts. Creatine kinase (CK), troponin I (TROP), eosinophil count (EOS), and C-reactive protein (CRP) were obtained at baseline and weeks 1, 2, 3, and 4. Descriptive statistics were calculated for demographic and clinical variables. Student's t test and chi-squared test were used to compare means and proportions between initial exposure and restart groups.

RESULTS

Clinical features and laboratory tests suggestive of PrMy were seen in 4 patients (5.3%) in initial exposure group and none in restart group. 3.5% of TROP levels were abnormal in initial exposure group and no abnormal levels were found in the restart group. 30% and 46% of CK, 23% and 39% of CRP, and 14% and 23% of EOS were abnormal in initial exposure group and restart groups, respectively.

CONCLUSIONS

PrMy was common (5.3%) during clozapine initiation. Prospective management through serial laboratory monitoring with weekly TROP levels was sensitive enough to allow for timely clozapine discontinuation.

Chronic stress pathology and ketamine-induced alterations in functional connectivity in major depressive disorder: An abridged review of the clinical evidence

A paradigm shift in the conceptualization of the neurobiology of depression and the serendipitous discovery of ketamine's rapid-acting antidepressant (RAAD) effects has ushered in a new era of innovative research and novel drug development. Since the initial discovery of ketamine's RAAD effects, multiple studies have supported its short-term efficacy for fast-tracked improvements in treatment-resistant depression. Evidence from MRI studies have repeatedly demonstrated functional connectivity alterations in stress- and trauma-related disorders suggesting this may be a viable biomarker of chronic stress pathology (CSP). Human mechanistic studies further support this by coupling functional connectivity to ketamine's RAAD effects including connectivity to glutamate neurotransmission, ketamine to normalized connectivity, and these advantageous normalizations to symptom improvement/ketamine response. This review provides an abridged discussion of the suspected neurobiological underpinnings of ketamine's RAAD effects, highlighting ketamine-induced alterations in prefrontal, striatal, and anterior cingulate cortex functional connectivity in major depressive disorder. We present a model of CSP underscoring the role of synaptic loss and dysconnectivity and discuss how ketamine may be used both as (1) a treatment to restore and normalize these stress-induced neural alterations and (2) a tool to study potential biomarkers of CSP and treatment response. We conclude by noting challenges and future directions including heterogeneity, sex differences, the role of early life stress, and the need for proliferation of new methods, paradigms, and tools that will optimize signal and allow analyses at different levels of complexity, according to the needs of the question at hand, perhaps by thinking hierarchically about both clinical and biological phenotypes.

Systematic review and meta-analysis of rates of clozapine-associated myocarditis and cardiomyopathy

BACKGROUND

Clozapine is the most effective medication for treatment refractory schizophrenia, but is associated with cardiac adverse drug reactions. Myocarditis and cardiomyopathy are the most serious cardiac adverse drug reactions although reported rates of these conditions vary in the literature. We systematically reviewed and meta-analysed the event rates, the absolute death rates and case fatality rates of myocarditis and cardiomyopathy associated with clozapine.

METHODS

PubMed, EMBASE and PsycINFO were searched for studies that reported on the incidence of cardiomyopathy or myocarditis in people exposed to clozapine. Data were meta-analysed using a random effects model, with subgroup analysis on study size, time frame, region, quality, retrospective vs prospective, and diagnostic criteria of myocarditis or cardiomyopathy.

RESULTS

28 studies of 258,961 people exposed to clozapine were included. The event rate of myocarditis was 0.007 (95% confidence interval [CI] = [0.003, 0.016]), absolute death rate was 0.0004 (95% CI = [0.0002, 0.0009]) and case fatality rate was 0.127 (95% CI = [0.034, 0.377]). The cardiomyopathy event rate was 0.006 (95% CI = [0.002, 0.023]), absolute death rate was 0.0003 (95% CI = [0.0001, 0.0012]) and case fatality rate was 0.078 (95% CI = [0.018, 0.285]). Few included studies provided information on criteria for diagnosis of myocarditis and cardiomyopathy. Event rates of cardiomyopathy and myocarditis were higher in Australia.

CONCLUSION

Clarity of diagnostic criteria for myocarditis remains a challenge. Observation bias may, in part, influence higher reported rates in Australia. Monitoring for myocarditis is warranted in the first 4 weeks, and treatment of comorbid metabolic syndrome and diabetes may reduce the risk of cardiomyopathy. The risks of myocarditis and cardiomyopathy are low and should not present a barrier to people with treatment refractory schizophrenia being offered a monitored trial of clozapine.

Antipsychotic drugs and sudden cardiac death: A literature review of the challenges in the prediction, management, and future steps

Sudden cardiac death (SCD) is relatively uncommon, yet it is a deadly consequence of some antipsychotic medications in patients with psychiatric disorders. The widespread concerns about the adverse cardiac effects associated with antipsychotics and their unpredictable nature have led to a restriction on the use of some antipsychotic medications. Recent progress has been made in the identification of important genetic factors that may contribute to the adverse complication of antipsychotic drugs, suggesting that high-risk individuals can be identified prior to initiating therapy. In addition, some high-tech smart wearable medical devices have recently been developed, allowing users to record and analyze the electrocardiogram (ECG) in couple with artificial intelligence (AI) technologies, and notifying of irregular heart rhythms or arrhythmias, a medical condition well documented in most SCD cases. In this literature review, we summarize recent advances in understanding the link between SCD and antipsychotic drug usage, as well as in utilizing wearable medical devices for monitoring of cardiac arrhythmias. New strategies for improving the care of patients receiving antipsychotic medications are proposed. As it is now possible to evaluate the risk of SCD in patients on antipsychotic medications, preventative measures and close monitoring may be used to detect the early signs of adverse cardiac events and SCD.

Understanding and managing cardiac side-effects of second-generation antipsychotics in the treatment of schizophrenia

Second-generation antipsychotic medications (SGAs) have advanced the treatment of schizophrenia over the past 30 years. However, a number of potentially life-threatening cardiac side-effects associated with these treatments concern and can discourage prescribers from administering these evidence-based treatments. This review provides a practical, psychiatrist-oriented understanding of the relative frequencies, mechanisms, investigations and treatments associated with these cardiac toxicities. We aim to highlight that these are relatively rare complications of an effective class of drug and to promote the advantages of early involvement of cardiologists in the psychiatric multidisciplinary team to guide the investigation and management of these conditions.

LEARNING OBJECTIVES

After reading this article you will be able to: •

[Fatigue, breathlessness and chest pain in a 31-year-old man with schizoaffective disorder]

BACKGROUND

Clozapine is an alternative antipsychotic medication used to control symptoms of schizophrenia and to reduce risks of suicidal behavior in patients who did not adequately respond to standard medication. Due to severe side effects including cardiomyopathy and myocarditis its clinical use is limited.

CASE REPORT

A 31-year-old man of east European descent presented to the emergency medical department with fatigue, shortness of breath and chest pain. Due to a schizoaffective disorder he was treated with clozapine and lithium. Echocardiography revealed severely impaired left ventricular systolic function. After exclusion of coronary artery disease by coronary angiography an endomyocardial biopsy was performed according to the guidelines. This confirmed the clinically suspected toxic cardiomyopathy. Therefore, antipsychotic treatment was immediately changed and state of the art heart failure medication was started resulting in a clear improvement of left ventricular function.

CONCLUSION

In patients treated with clozapine or lithium and clinical signs of heart failure, toxic cardiomyopathy should be considered.

Pericardial Effusion: Rare Adverse Effect of Clozapine

Clozapine is a dibenzodiazepine antipsychotic used for resistant schizophrenia, which is known to be associated with side effects such as agranulocytosis, seizures, weight gain, and less commonly myocarditis/ cardiomyopathy. We present a case of a 20-year-old female who presented with chest pain, shortness of breath, and cough. She was later found to have clozapine-induced pericardial effusion that resolved after discontinuation of clozapine therapy. Our case discloses the importance to consider clozapine in the differential diagnosis of pericardial effusion as discontinuation of the drug leads to resolution of effusion, with no need for further treatment.

Undiagnosed cardiovascular disease prior to cardiovascular death in individuals with severe mental illness

OBJECTIVE

To examine whether individuals with schizophrenia (SCZ) or bipolar disorder (BD) had equal likelihood of not being diagnosed with cardiovascular disease (CVD) prior to cardiovascular death, compared to individuals without SCZ or BD.

METHODS

Multivariate logistic regression analysis including nationwide data of 72 451 cardiovascular deaths in the years 2011-2016. Of these, 814 had a SCZ diagnosis and 673 a BD diagnosis in primary or specialist health care.

RESULTS

Individuals with SCZ were 66% more likely (OR: 1.66; 95% CI: 1.39-1.98), women with BD were 38% more likely (adjusted OR: 1.38; 95% CI: 1.04-1.82), and men with BD were equally likely (OR: 0.88, 95% CI: 0.63-1.24) not to be diagnosed with CVD prior to cardiovascular death, compared to individuals without SMI. Almost all (98%) individuals with SMI and undiagnosed CVD had visited primary or specialized somatic health care prior to death, compared to 88% among the other individuals who died of CVD.

CONCLUSION

Individuals with SCZ and women with BD are more likely to die due to undiagnosed CVD, despite increased risk of CVD and many contacts with primary and specialized somatic care. Strengthened efforts to prevent, recognize, and treat CVD in individuals with SMI from young age are needed.

Clozapine and Long-Term Mortality Risk in Patients With Schizophrenia: A Systematic Review and Meta-analysis of Studies Lasting 1.1-12.5 Years

INTRODUCTION

Patients with schizophrenia have an elevated mortality risk compared to the general population, with cardiovascular-related deaths being the leading cause. The role of clozapine use in the long-term mortality risk is unclear. While clozapine treatment may increase the risk for cardiovascular mortality, it may have protective effects regarding suicidal behavior.

METHODS

We systematically searched EMBASE, MEDLINE, and PsycINFO and reviewed studies that used a long-term follow-up (ie, >52 weeks) and reported on mortality in adults diagnosed with schizophrenia-spectrum disorders who had received clozapine treatment.

RESULTS

Altogether, 24 studies reported on 1327 deaths from any causes during 217691 patient years in patients treated with clozapine. The unadjusted mortality rate in 22 unique samples during a follow-up of 1.1-12.5 (median = 5.4) years was 6.7 (95% confidence interval [CI] = 5.4-7.9) per 1000 patient years. Long-term, crude mortality rate ratios were not significantly lower in patients ever treated with clozapine during follow-up, but significantly lower in patients continuously treated with clozapine compared to patients with other antipsychotics (mortality rate ratio = 0.56, 95% CI = 0.36-0.85, P-value = .007). Few studies reported on rates of long-term cause-specific mortality (suicide and ischemic heart disease), which showed no significant difference in patients using clozapine compared to patients using other antipsychotics. Statistical heterogeneity was high in all analyses.

DISCUSSION

Continuous clozapine treatment in schizophrenia patients was associated with a significantly lower long-term all-cause mortality rate compared to other antipsychotic use. These findings, combined with the known efficacy of clozapine, give reason to re-evaluate the hesitancy to prescribe clozapine in regular care settings.

TRIAL REGISTRATION

PROSPERO CRD42017069390.

Clozapine-induced myocarditis: Two case reports and review of clinical presentation and recognition

Myocarditis is a potentially fatal cardiac disease marked by inflammation of the heart muscle. With a noted black-box warning, rates of clozapine-induced myocarditis are reportedly as high as 3%. Since the first case of clozapine-induced myocarditis was documented in 1994, more than 250 cases have been described in literature with an approximate 33% case-fatality rate. We report 2 cases of patients with primary psychotic disorders treated with clozapine, who developed signs and symptoms of myocarditis. The first was a 35-year-old white male patient with a primary diagnosis of schizoaffective disorder (bipolar type) who was initiated on clozapine after nonresponse to several therapies. On day 26, the patient was admitted to the emergency department for chest pain presenting with eosinophilia and notable elevations in several biomarkers, including troponin and C-reactive protein. The second patient was a 45-year-old black male who was initiated on clozapine for treatment-resistant schizophrenia. On day 13, the patient reported cardiac-related concerns (tachycardia) and flu-like symptoms resulting in hospitalization. Similarly, this patient demonstrated elevated biomarkers (troponin and creatine kinase). Both patients experienced resolution of symptoms after discontinuation of clozapine. Clozapine was not rechallenged for either patient. Review of literature further elucidates the relationship between clozapine and myocarditis, including potential risk factors, pathophysiology, and symptom presentation. Due to the potentially fatal nature of this condition, clinical vigilance and awareness is warranted upon initiation of clozapine through monitoring of symptoms along with cardiac and inflammatory biomarkers as indicated.

Potentially fatal outcomes associated with clozapine

Clozapine has been shown to be the most efficacious therapy for treatment resistant schizophrenia, estimated at one third of all schizophrenia cases. There is significant morbidity and mortality associated with clozapine including risk of agranulocytosis, aspiration pneumonia, bowel ischemia, myocarditis, seizures, and weight gain. Here we present a case of a 62-year-old man with chronic paranoid schizophrenia refractory to numerous antipsychotics who was started on clozapine therapy during an acute inpatient psychiatric admission. Within three weeks of starting clozapine, the patient developed flu-like symptoms, pleuritic chest pain, and was sent to a medical hospital for evaluation. After transfer, the patient had a rapidly deteriorating course with newly developed congestive heart failure, acute respiratory failure requiring intubation, and cardiovascular collapse requiring vasopressors. The patient expired within two days of transfer and four days after initial symptoms developed. The underlying etiology in this case is likely clozapine induced myocarditis leading to rapid cardiovascular collapse and death. Mortality with clozapine induced myocarditis has been estimated up to 24%. Given that 90% of clozapine cardiotoxic sequelae are seen in the first month post-initiation, more rigorous post-initiation surveillance is recommended for the first four weeks of clozapine with weekly cardiac enzymes (troponins, creatinine kinase-MB), EKG, and acute inflammatory markers (C-reactive protein, and erythrocyte sedimentation rate).

Clozapine-induced cardiomyopathy and myocarditis monitoring: A systematic review

The use of clozapine requires monitoring the absolute neutrophil count because of the risk of agranulocytosis, but other potentially fatal adverse events associated with clozapine (specifically, myocarditis and cardiomyopathy) do not have mandatory procedures. We performed a systematic review of English-language articles to synthesize an evidence-based approach for myocarditis and cardiomyopathy monitoring. Articles published from January 1988 through February 2017 were identified through a search of Ovid MEDLINE, Ovid Embase, Ovid Cochrane Database of Systematic Reviews, Web of Science, Scopus, and Google Scholar. Selected articles were required to relate to myocarditis or cardiomyopathy in humans from exposure to clozapine. A total of 144 articles were included. Recommendations varied widely. Some authors recommended baseline laboratory monitoring, with or without follow-up testing, for C-reactive protein, creatine kinase MB, and troponin. Electrocardiography was commonly recommended, and echocardiography was less commonly recommended. The expense of monitoring was a consideration. A unanimous recommendation was to stop the use of clozapine and seek a cardiovascular consultation if myocarditis or cardiomyopathy is suspected. Although there is general agreement on which tests to perform for confirming myocarditis and cardiomyopathy, preemptive screening for these clozapine-induced conditions is controversial, and cost and barriers for the use of clozapine are concerns. For asymptomatic patients receiving clozapine, testing could include baseline electrocardiography, echocardiography as part of a cardiac consultation if patients have cardiac disease or risk factors, and monitoring of C-reactive protein and troponin as indicated.

Sudden death in schizophrenia

PURPOSE OF REVIEW

To examine the recent literature regarding sudden death in patients with schizophrenia and synthesize salient conclusions based on this evidence.

RECENT FINDINGS

Sudden cardiac death (SCD) is the largest subset of sudden unexpected death (SUD), with up to 40% of SUD from cardiovascular causes. SCD has been associated with exposure to both first and second-generation antipsychotics. Clozapine [odds ratio (OR) 3.67, 95% confidence interval (CI) 1.94-6.94] confers the highest risk of SCD followed by risperidone (OR 3.04, 95% CI 2.39-3.86) then olanzapine (OR 2.04, 95% CI 1.52-2.74). SCD not associated with antipsychotic use has been correlated to several modifiable and nonmodifiable risk factors - obesity, smoking, dyslipidemia, diabetes, hypertension, age, sex, and history of cardiovascular disease. Other subsets of SUD include hematological and pulmonary causes, including agranulocytosis leading to sepsis, deep vein thrombosis leading to pulmonary embolisms, and aspiration pneumonia leading to sepsis.

SUMMARY

There is a huge paucity in genetic and pharmacogenetic data focused on SUD in schizophrenia. Future studies should emphasize the genetic aspects as well as clarify the underlying molecular mechanisms of these pathways. Additionally, early detection of those patients at high risk for SUD and discovery of preventive measures should also be emphasized.

Safety of antipsychotics for the treatment of schizophrenia: a focus on the adverse effects of clozapine

Clozapine, a dibenzodiazepine developed in 1961, is a multireceptorial atypical antipsychotic approved for the treatment of resistant schizophrenia. Since its introduction, it has remained the drug of choice in treatment-resistant schizophrenia, despite a wide range of adverse effects, as it is a very effective drug in everyday clinical practice. However, clozapine is not considered as a top-of-the-line treatment because it may often be difficult for some patients to tolerate as some adverse effects can be particularly bothersome (i.e. sedation, weight gain, sialorrhea etc.) and it has some other potentially dangerous and life-threatening side effects (i.e. myocarditis, seizures, agranulocytosis or granulocytopenia, gastrointestinal hypomotility etc.). As poor treatment adherence in patients with resistant schizophrenia may increase the risk of a psychotic relapse, which may further lead to impaired social and cognitive functioning, psychiatric hospitalizations and increased treatment costs, clozapine adverse effects are a common reason for discontinuing this medication. Therefore, every effort should be made to monitor and minimize these adverse effects in order to improve their early detection and management. The aim of this paper is to briefly summarize and provide an update on major clozapine adverse effects, especially focusing on those that are severe and potentially life threatening, even if most of the latter are relatively uncommon.

Intravenous Immunoglobulin and Methylprednisolone for Clozapine-Associated Perimyocarditis

CLINICAL FEATURES

Cardiotoxicity is a rare but serious side effect of clozapine. We present a case of a psychiatric patient on chronic clozapine 75 mg daily, who presented with congestive heart failure secondary to the cardiotoxic effects of the psychiatric medication.

THERAPEUTIC CHALLENGE

Conventional heart failure treatment failed to improve symptoms.

SOLUTION

A course of 40 mg of intravenous immunoglobulin and 125 mg of steroids was implemented, after which the patient made a full recovery. We hope to raise awareness of concurrent clozapine-induced pericarditis and myocarditis and propose a role of intravenous immunoglobulin and steroids in the treatment of drug-induced cardiomyopathy.

Clozapine-induced myocarditis

Approved in 1989 for the management of treatment-resistant schizophrenia, Clozapine is a last-line atypical antipsychotic drug used with increasing frequency. In addition to its well-known side effect of agranulocytosis, this drug also carries with it rare but serious adverse cardiovascular risk of myocarditis. We present a patient on Clozapine who was admitted to the cardiology service with chest pain, ST segment elevations and elevated troponin concerning for acute myocardial infarction. Evaluation with imaging revealed decreased left ventricular function, however, no coronary artery disease was present on catheterization; findings consistent with a diagnosis of myocarditis. Subsequent discontinuation of the patient's Clozapine and initiation of brief supportive medical therapy resulted in full recovery of systolic left ventricular function. Given the potential cardiovascular mortality risk, it is important for physicians on cardiology services caring for psychiatric patients to be aware of the presentation of symptoms, diagnostic findings and management of Clozapine induced myocarditis.