Sudden cardiac death and antipsychotics Part 2: Monitoring and prevention

Content Validation of an Algorithm for the Assessment, Management and Monitoring of Drug-Induced QTc Prolongation in the Psychiatric Population

BACKGROUND

QTc interval (QTcI) prolongation leads to serious complications, making it a concern for clinicians. Assessing the risk of QTcI prolongation in the psychiatric population is important because they are exposed to multiple medications known to increase the risk of life-threatening arrhythmias.

AIM

The study aims to validate the content of an algorithm for the assessment, management and monitoring of drug-induced QTc prolongation in the psychiatric population.

METHODOLOGY

Qualitative semi-structured interviews of cardiologists, to gather information regarding their approach in assessing the risk of drug-induced QTc prolongation at the time of prescribing. After the interview, an orientation to the algorithm was provided with a link to a cross-sectional, anonymous survey. The online survey included quantitative and qualitative components to gather feedback on the relevance and appropriateness of each step in the algorithm.

RESULTS

Interview responses were incorporated into 4 themes. Responses indicated a lack of a unified protocol when assessing QTcI prolongation, which supports the need of an algorithm that includes a verified risk scoring tool. Quantitative survey results showed a mean score ranging from 3.08 to 3.67 out of 4 for the appropriateness of the algorithm's steps, 3.08 to 3.58 for the safety and 3.17 to 3.75 for the reliability of references used. Additional analysis using the modified kappa and I-CVI statistical measures indicate high validity of contents and high degree of agreement between raters. As per the open-ended questions, cardiologists supported the implementation of the algorithm; however, they recommended simplification of the steps as they appear to be cumbersome.

CONCLUSION

The results demonstrate that the implementation of the algorithm after minor alterations can prove to be useful as a tool for the risk assessment of QTc prolongation. Further validation of the algorithm with mental health pharmacists and clinicians will be conducted as a separate phase of the study.

QTc Prolongation Associated With Psychiatric Medications: A Retrospective Cross-Sectional Study of Adult Inpatients

OBJECTIVE

The aim of our study was to assess the impact of psychiatric medications and concomitant risk factors on the prevalence of QTc prolongation and torsades de pointes (TdP) in hospitalized subjects. We examined the association between individual risk scores and QTc prolongation and proposed an evidence-based protocol for electrocardiogram monitoring on psychotropic medications.

METHOD

Electrocardiograms (ECGs) of subjects hospitalized over a 1-year period were analyzed for QTc prolongation, associated risk factors, and use of medications. Analysis was performed using logistic regression to identify independent predictors of QTc prolongation, and the Pearson χ test was used for risk score assessment.

RESULTS

A total of 1249 ECGs of 517 subjects were included in this study. Eighty-seven subjects had QTcB intervals greater than 470 milliseconds for females and greater than 450 milliseconds for males. Twelve (2.3%) subjects had QTcB of 500 milliseconds or greater, or greater than 60 milliseconds of change from baseline. Of these subjects, only 1 case of QTc interval change was related to routine use of psychiatric medications. There were no incidents of TdP. Age, diabetes, hypokalemia, overdose, diphenhydramine, and haloperidol were significant independent predictors of QTc prolongation. Risk scores were significantly correlated with QTc prolongation (P = 0.001).

CONCLUSION

Our retrospective review study found that the occurrence of TdP and QTc prolongation was low in this subject population. QT abnormalities were associated with known risk factors, and risk scores correlated well with QTc prolongation. Providers can use the protocol proposed in this study, which incorporates risk scores and the CredibleMeds classification system to determine the need for ECG monitoring and to guide treatment.

Rapid tranquillisation: the science and advice

‘Rapid tranquillisation’ refers to the use of medication to calm highly agitated individuals experiencing mental disorder who have not responded to non-pharmacological approaches. Commonly it is the initial stage in the treatment of severe and enduring illness. Using medication in this way requires particularly robust evidence of efficacy and the management of side-effects. This article attempts to integrate current understanding of the neurochemical mechanisms of underlying illness and drug actions with therapeutic interventions. It distinguishes arousal from agitation, and effects on sedation from tranquillisation. It reviews critically the practice of rapid tranquillisation in the light of new evidence, changes in the NICE guidelines and British National Formulary recommendations and a national audit (POMH-UK). Broader aspects of management, known as ‘restrictive practices’ (such as control and restraint and seclusion), psychological support of team members, incident reporting, risk assessment, monitoring and medico-legal aspects are not covered.

LEARNING OBJECTIVES

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DECLARATION OF INTEREST

None.

Joint BAP NAPICU evidence-based consensus guidelines for the clinical management of acute disturbance: De-escalation and rapid tranquillisation

The British Association for Psychopharmacology and the National Association of Psychiatric Intensive Care and Low Secure Units developed this joint evidence-based consensus guideline for the clinical management of acute disturbance. It includes recommendations for clinical practice and an algorithm to guide treatment by healthcare professionals with various options outlined according to their route of administration and category of evidence. Fundamental overarching principles are included and highlight the importance of treating the underlying disorder. There is a focus on three key interventions: de-escalation, pharmacological interventions pre-rapid tranquillisation and rapid tranquillisation (intramuscular and intravenous). Most of the evidence reviewed relates to emergency psychiatric care or acute psychiatric adult inpatient care, although we also sought evidence relevant to other common clinical settings including the general acute hospital and forensic psychiatry. We conclude that the variety of options available for the management of acute disturbance goes beyond the standard choices of lorazepam, haloperidol and promethazine and includes oral-inhaled loxapine, buccal midazolam, as well as a number of oral antipsychotics in addition to parenteral options of intramuscular aripiprazole, intramuscular droperidol and intramuscular olanzapine. Intravenous options, for settings where resuscitation equipment and trained staff are available to manage medical emergencies, are also included.

Cardiovascular monitoring with acetylcholinesterase inhibitors: a clinical protocol

There has been significant anxiety among prescribers regarding the potential for cardiac adverse effects associated with acetylcholinesterase (AChE) inhibitors in Alzheimer's disease. There is no consensus on how to manage this cardiovascular risk, and memory clinics vary widely in their practice. Review of published evidence reveals that the incidence of cardiovascular side-effects is low, and that serious adverse events are rare. Intensive cardiovascular screening such as pre-treatment electrocardiograms or 24 h cardiac monitoring is not justified. Furthermore, there are no high-risk groups to target. This article suggests pragmatic guidelines for managing cardiovascular risk in patients receiving AChE inhibitors. The guidelines are intended to be easy to incorporate into routine clinical practice in a memory clinic.

Competence of psychiatric clinicians in interpreting electrocardiograms and QT intervals: can they do this? Does it matter?

Aims and Method

We assessed the abilities of trainee and consultant psychiatrists in reading and interpreting electrocardiograms (ECGs) and QT intervals using a questionnaire and standardised ECG.

Results

Only 5% of our sample of trainee and consultant psychiatrists could correctly indicate a QTc interval. Performances on other measures, such as rate were also poor, with senior house officers performing better than consultants.

Clinical Implications

The increased awareness of problems caused by antipsychotics has not been reflected in improved knowledge of ECGs among psychiatrists. Machines do not reliably calculate QT intervals. We therefore urge better training and understanding of ECGs for psychiatrists.

Clinicians' adherence to clinical practice guidelines for cardiac function monitoring during antipsychotic treatment: a retrospective report on 434 patients with severe mental illness

BACKGROUND

Severe mental illness (SMI) has considerable excess morbidity and mortality, a proportion of which is explained by cardiovascular diseases, caused in part by antipsychotic (AP) induced QT-related arrhythmias and sudden death by Torsade de Point (TdP). The implementation of evidence-based recommendations for cardiac function monitoring might reduce the incidence of these AP-related adverse events. To investigate clinicians' adherence to cardiac function monitoring before and after starting AP, we performed a retrospective assessment of 434 AP-treated SMI patients longitudinally followed-up for 5 years at an academic community mental health center.

METHODS

We classified antipsychotics according to their risk of inducing QT-related arrhythmias and TdP (Center for Research on Therapeutics, University of Arizona). We used univariate tests and multinomial or binary logistic regression model for data analysis.

RESULTS

Univariate and multinomial regression analysis showed that psychiatrists were more likely to perform pre-treatment electrocardiogram (ECG) and electrolyte testing with AP carrying higher cardiovascular risk, but not on the basis of AP pharmacological class. Univariate and binomial regression analysis showed that cardiac function parameters (ECG and electrolyte balance) were more frequently monitored during treatment with second generation AP than with first generation AP.

CONCLUSIONS

Our data show the presence of weaknesses in the cardiac function monitoring of AP-treated SMI patients, and might guide future interventions to tackle them.

Methadone safety: a clinical practice guideline from the American Pain Society and College on Problems of Drug Dependence, in collaboration with the Heart Rhythm Society

Methadone is used for the treatment of opioid addiction and for treatment of chronic pain. The safety of methadone has been called into question by data indicating a large increase in the number of methadone-associated overdose deaths in recent years that has occurred in parallel with a dramatic rise in the use of methadone for chronic pain. The American Pain Society and the College on Problems of Drug Dependence, in collaboration with the Heart Rhythm Society, commissioned an interdisciplinary expert panel to develop a clinical practice guideline on safer prescribing of methadone for treatment of opioid addiction and chronic pain. As part of the guideline development process, the American Pain Society commissioned a systematic review of various aspects related to safety of methadone. After a review of the available evidence, the expert panel concluded that measures can be taken to promote safer use of methadone. Specific recommendations include the need to educate and counsel patients on methadone safety, use of electrocardiography to identify persons at greater risk for methadone-associated arrhythmia, use of alternative opioids in patients at high risk of complications related to corrected electrocardiographic QTc interval prolongation, careful dose initiation and titration of methadone, and diligent monitoring and follow-up. Although these guidelines are based on a systematic review, the panel identified numerous research gaps, most recommendations were based on low-quality evidence, and no recommendations were based on high-quality evidence.

PERSPECTIVE

This guideline, based on a systematic review of the evidence on methadone safety, provides recommendations developed by a multidisciplinary expert panel. Safe use of methadone requires clinical skills and knowledge in use of methadone to mitigate potential risks, including serious risks related to risk of overdose and cardiac arrhythmias.

Electrocardiographic monitoring for new prescriptions of quetiapine co-prescribed with acetylcholinesterase inhibitors or memantine from 2005 to 2009. A population study on community-dwelling older people in Italy

PURPOSE

The aims of this study are to analyse, in community-dwelling people aged 65+ living in Italy's Lombardy Region, electrocardiographic (ECG) monitoring for new users of the atypical antipsychotic quetiapine co-prescribed with acetylcholinesterase inhibitors (AChEIs) or memantine and to find independent predictors of ECG monitoring before and after the starting of this prescription.

METHODS

The Lombardy Region's administrative health database was used to retrieve prescriptions of ECG exams as well as prevalence rates of subjects aged 65+ who were prescribed such psychotropic drugs from 2005 to 2009. Multivariable analyses were adjusted for age, sex, number of drugs, treatment with beta-blockers, digoxin, verapamil or diltiazem, any antiarrhythmic drug and antidepressants.

RESULTS

Overall 2,623 community-dwelling older people started therapy with quetiapine, co-prescribed with AChEIs or memantine, during these 5 years. At least one ECG was performed in 714 cases (27.2 %) in the 6 months before-and in 398 cases (15.2 %) within 3 months after-the starting of this prescription. ECG monitoring was performed both before and after starting quetiapine in only 160 cases (6.1 %). At multivariable analyses, number of drugs taken, beta-blocker and antiarrhythmic drug use were found to be independent correlates of ECG monitoring whereas female sex was associated with a lower probability of receiving an ECG within 3 months after the initiation of quetiapine (odds ratio 0.78, 95 % CI 0.62-0.98).

CONCLUSIONS

ECG monitoring for new prescriptions of quetiapine in older people suffering from behavioural and psychological symptoms in dementia was actually performed infrequently, independently of the age of drug users, especially in women. Our results support the need for greater awareness within the medical community of the importance of such ECG monitoring.

QTc prolongation with antipsychotics: is routine ECG monitoring recommended?

Whether or not QTc interval should be routinely monitored in patients receiving antipsychotics is a controversial issue, given logistic and fiscal dilemmas. There is a link between antipsychotic medications and prolongation of QTc interval, which is associated with an increased risk of torsade de pointes (TdP). Our goal is to provide clinically practical guidelines for monitoring QTc intervals in patients being treated with antipsychotics. We provide an overview of the pathophysiology of the QT interval, its relationship to TdP, and a discussion of the QT prolonging effects of antipsychotics. A literature search for articles relevant to the QTc prolonging effects of antipsychotics and TdP was conducted utilizing the databases PubMed and Embase with various combinations of search words. The overall risk of TdP and sudden death associated with antipsychotics has been observed to be low. Medications, genetics, gender, cardiovascular status, pathological conditions, and electrolyte disturbances have been found to be related to prolongation of the QTc interval. We conclude that, while electrocardiogram (ECG) monitoring is useful when administering antipsychotic medications in the presence of co-existing risk factors, it is not mandatory to perform ECG monitoring as a prerequisite in the absence of cardiac risk factors. An ECG should be performed if the initial evaluation suggests increased cardiac risk or if the antipsychotic to be prescribed has been established to have an increased risk of TdP and sudden death.

Challenges in managing a mother with a dual diagnosis of peripartum cardiomyopathy and paranoid schizophrenia - a case report

INTRODUCTION

Psychotic illness has a low incidence in the puerperal period. Peripartum cardiomyopathy as a complication of pregnancy is also rare.

CLINICAL CASE

We report a case where the above two conditions occurred simultaneously in a patient and posed significant difficulties in the clinical management. She was diagnosed as having paranoid schizophrenia and peripartum cardiomyopathy. Many of the antipsychotics were contraindicated, and electroconvulsive therapy could not be administered due to the added risks involved with regard to anesthesia. She was therefore managed with clonazepam and olanzapine.

DISCUSSION

This case highlights the challenges in a patient with a psychiatric illness presenting with comorbid physical illness.

Sudden cardiac death and antipsychotic medications: literature review

The review summarises the evidence from international publications on sudden cardiac death (SCD) in psychiatric patients receiving neuroleptics. Modern SCD definitions are presented, together with the relevant epidemiological data. The pathogenesis of fatal cardiac arrhythmias, caused by cardiotoxic effects of antipsychotic medications, is discussed. Electrocardiographic changes, in particular QT interval changes, as well as risk factors of SCD and main principles of its prevention, are described in detail.

Structural contributions of antipsychotic drugs to their therapeutic profiles and metabolic side effects

Antipsychotic drugs have various neuropharmacological properties as a result of their structural diversity. Despite their therapeutic benefits, most of the prescribed atypical antipsychotics can induce severe side effects, including weight gain, type II diabetes mellitus, and cardiovascular diseases. Among the developed atypical antipsychotic agents, tetracyclic dibenzodiazepine and thienobenzodiazepine compounds, particularly clozapine and olanzapine, are associated with the greatest weight gain and metabolic disturbances. However, the unique chemical structure of these compounds causes the low risk of side effects reported for typical antipsychotics (e.g. extrapyramidal symptoms and tardive dyskinesia). This report reviews the recent discovery of the potential role of the chemical structure of antipsychotics in their therapeutic properties and metabolic disturbances. By developing structure-activity relationship studies for atypical antipsychotics, we will improve our understanding of the structural modifications of these chemical classes that lead to reduced weight gain, which will be an invaluable step toward the discovery of the next generation of atypical antipsychotics. In this review, we suggest that a novel dibenzodiazepine or thienobenzodiazepine antipsychotic drug with lower affinity for H(1) receptors may significantly advance schizophrenia therapy.

Assessing QT interval prolongation and its associated risks with antipsychotics

Several antipsychotics are associated with the ventricular tachycardia torsade de pointes (TdP), which may lead to sudden cardiac death (SCD), because of their inhibition of the cardiac delayed potassium rectifier channel. This inhibition extends the repolarization process of the ventricles of the heart, illustrated as a prolongation of the QT interval on a surface ECG. SCD in individuals receiving antipsychotics has an incidence of approximately 15 cases per 10,000 years of drug exposure but the exact association with TdP remains unknown because the diagnosis of TdP is uncertain. Most patients manifesting antipsychotic-associated TdP and subsequently SCD have well established risk factors for SCD, i.e. older age, female gender, hypokalaemia and cardiovascular disease. QT interval prolongation is the most widely used surrogate marker for assessing the risk of TdP but it is considered somewhat imprecise, partly because QT interval changes are subject to measurement error. In particular, drug-induced T-wave changes (e.g. flattening of the T-wave) may complicate the measurement of the QT interval. Furthermore, the QT interval depends on the heart rate and a corrected QT (QTc) interval is often used to compensate for this. Several correction formulas have been suggested, with Bazett's formula the most widely used. However, Bazett's formula overcorrects at a heart rate above 80 beats per minute and, therefore, Fridericia's formula is considered more appropriate to use in these cases. Several other surrogate markers for TdP have been developed but none of them is clinically implemented yet and QT interval prolongation is still considered the most valid surrogate marker. Although automated QT interval determination may offer some assistance, QT interval determination is best performed by a cardiologist skilled in its measurement. A QT interval >500 ms markedly increases the risk for TdP and SCD, and should lead to discontinuation of the offending drug and, if present, correction of underlying electrolyte disturbances, particularly serum potassium and magnesium derangements. Before prescribing antipsychotics that may increase the QTc interval, the clinician should ask about family and personal history of SCD, presyncope, syncope and cardiac arrhythmias, and recommend cardiology consultation if history is positive.

Proarrhythmic risk with antipsychotic and antidepressant drugs: implications in the elderly

The quinidine-like effects of some antidepressant drugs (particularly tricyclic antidepressants) and many antipsychotic drugs (particularly the phenothiazines) confound treatment of psychosis and depression in patients with major mental illness. This is especially true among elderly patients with existing risk factors for corrected QT (QTc) interval prolongation. We used PubMed, previously reported review articles and the extensive personal files of the authors to identify cases of subjects aged>or=60 years who developed QTc interval prolongation, polymorphic ventricular tachycardia (PVT)/torsade de pointes (TdP) and/or sudden cardiac death while taking antipsychotic or antidepressant drugs or a combination of these medications. We identified 37 patients who had taken, in total, 46 antipsychotic or antidepressant drugs. Our most striking finding was that almost four-fifths of our cases involved women. When the 14 critically ill subjects receiving haloperidol intravenously were excluded, 91.3% of our subjects were women. Almost three-quarters of our study subjects had cardiovascular disease. Intravenous administration of haloperidol in the critically ill and profoundly agitated elderly warrants particular comment. Of the 14 subjects in this category identified, six were men and eight were women. In 13 cases, the drug dose far exceeded the 2 mg necessary to produce an antipsychotic effect. These clinicians were using an agent to achieve sedation that usually requires very high doses in the critically ill and profoundly agitated elderly to achieve this effect. Inclusion criteria for our literature review required antipsychotic and/or antidepressant drug-induced QTc interval prolongation. Even so, our finding that 31 of our 37 subjects developed PVT is sobering. However, the reader should not conclude that drug-induced QTc interval prolongation is highly predictive of PVT or its TdP subtype. All of our study subjects had at least two risk factors for TdP, with age and sex being the most common. We included the rare case of a patient with congenital long QT syndrome who developed further lengthening of the QTc interval and TdP when prescribed an antidepressant drug well known to produce QTc interval prolongation. We conclude with recommendations for clinicians not expert in the specialty of cardiology to deal with the many questions raised in this review. Specifically, such clinicians treating elderly patients with antipsychotic and antidepressant drugs that may prolong the QTc interval should aggressively obtain a baseline ECG for elderly female patients with additional risk factors such as personal or family history of pre-syncope or syncope, electrolyte disturbances or cardiovascular disease. Elderly male patients are also subject to QTc interval prolongation when such risk factors are present. It is important that the clinicians themselves inspect ECGs. If the QT interval is more than half the RR interval, QTc interval prolongation is likely to be present. In such cases, a cardiology colleague interested in QTc interval issues and TdP should be asked to review the ECG. Finally, nothing in our recommendations replaces meticulous attention to US FDA guidelines in the package insert of each drug.

Metabolic and Cardiac Side Effects of Second-generation Antipsychotics: What Every Clinician Should Know

In 2007, 5 of the 7 second-generation antipsychotics were listed in the Top 200 Drugs prescribed by retail sales in the United States. Cardiovascular disease is the leading cause of natural death in individuals with schizophrenia. Second-generation antipsychotics have been implicated with metabolic and cardiovascular adverse effects, and it is important for nonpsychiatric practitioners to be familiar with the monitoring parameters recommended for these agents. This article discusses the risk of weight gain, hyperglycemia, hyperlipidemia, hyperprolactinemia, and cardiovascular concerns associated with second-generation antipsychotic agents. It also discusses the proposed mechanisms for each of these adverse effects. Furthermore, it reviews suggested monitoring parameters to help manage cardiovascular disease in this patient population, and to improve the gap that exists between mental health care and physical health care in the schizophrenic population.

Sudden cardiac death secondary to antidepressant and antipsychotic drugs

A number of antipsychotic and antidepressant drugs are known to increase the risk of ventricular arrhythmias and sudden cardiac death. Based largely on a concern over QT prolongation and the development of life-threatening arrhythmias, a number of antipsychotic drugs have been temporarily or permanently withdrawn from the market or their use restricted. Some antidepressants and antipsychotics have been linked to QT prolongation and the development of Torsade de pointes arrhythmias, whereas others have been associated with a Brugada syndrome phenotype and the development of polymorphic ventricular arrhythmias. This review examines the mechanisms and predisposing factors underlying the development of cardiac arrhythmias, and sudden cardiac death, associated with antidepressant and antipsychotic drugs in clinical use.

Physical health and schizophrenia

PURPOSE OF REVIEW

Patients with schizophrenia have higher than expected rates of morbidity and mortality. It is debatable whether this is related to shared risk factors, antipsychotic medication or inherent to the condition itself. This review will describe this association and the recent advances in the field.

RECENT FINDINGS

The majority of patients with schizophrenia have at least one chronic comorbid medical condition. In the absence of systematic screening this may or may not be brought to the attention of health professionals. The cause of high rates of physical illness appears to be multifactorial involving shared vulnerability and genetic factors. Yet it is vascular risk factors and the adverse effects of prescribed medication that are most amenable to intervention. Current atypical antipsychotics may offer neurological and cognitive benefits, but there is accumulating evidence of problems with weight gain, diabetes, lipid dysregulation, metabolic syndrome and sexual side effects.

SUMMARY

The physical health of patients with schizophrenia remains a concern. Yet the quality of medical and psychiatric care of patients with comorbid physical and mental health disorders has been shown to be unsatisfactory in several areas. We suggest that clinicians routinely assess and monitor physical health needs of patients with serious mental illness.