Clozapine use in childhood and adolescent schizophrenia: A nationwide population-based study

CLEAR - clozapine in early psychosis: study protocol for a multi-centre, randomised controlled trial of clozapine vs other antipsychotics for young people with treatment resistant schizophrenia in real world settings

BACKGROUND

Clozapine is an antipsychotic drug with unique efficacy, and it is the only recommended treatment for treatment-resistant schizophrenia (TRS: failure to respond to at least two different antipsychotics). However, clozapine is also associated with a range of adverse effects which restrict its use, including blood dyscrasias, for which haematological monitoring is required. As treatment resistance is recognised earlier in the illness, the question of whether clozapine should be prescribed in children and young people is increasingly important. However, most research to date has been in older, chronic patients, and evidence regarding the efficacy and safety of clozapine in people under age 25 is lacking. The CLEAR (CLozapine in EARly psychosis) trial will assess whether clozapine is more effective than treatment as usual (TAU), at the level of clinical symptoms, patient rated outcomes, quality of life and cost-effectiveness in people below 25 years of age. Additionally, a nested biomarker study will investigate the mechanisms of action of clozapine compared to TAU.

METHODS AND DESIGN

This is the protocol of a multi-centre, open label, blind-rated, randomised controlled effectiveness trial of clozapine vs TAU (any other oral antipsychotic monotherapy licenced in the British National Formulary) for 12 weeks in 260 children and young people with TRS (12-24 years old).

AIM AND OBJECTIVES

The primary outcome is the change in blind-rated Positive and Negative Syndrome Scale scores at 12 weeks from baseline. Secondary outcomes include blind-rated Clinical Global Impression, patient-rated outcomes, quality of life, adverse effects, and treatment adherence. Patients will be followed up for 12 months and will be invited to give consent for longer term follow-up using clinical records and potential re-contact for further research. For mechanism of action, change in brain magnetic resonance imaging (MRI) biomarkers and peripheral inflammatory markers will be measured over 12 weeks.

DISCUSSION

The CLEAR trial will contribute knowledge on clozapine effectiveness, safety and cost-effectiveness compared to standard antipsychotics in young people with TRS, and the results may guide future clinical treatment recommendation for early psychosis.

TRIAL REGISTRATION

ISRCTN Number: 37176025, IRAS Number: 1004947.

TRIAL STATUS

In set-up. Protocol version 4.0 01/08/23. Current up to date protocol available here: https://fundingawards.nihr.ac.uk/award/NIHR131175# /.

A new scale for the screening of childhood early psychotic symptoms

This study aimed to develop a new scale, the Early Psychotic Symptoms screening scale (EPSy), to assess the prodromes of psychotic symptoms in children aged 4 to 13 years. Two versions were proposed: one to assess the child's current behavior and one to assess the child's behavior when he/she was 2 years old. The second aim of this study was to investigate the presence of these symptoms at the age of 2 years and their evolution up to the child's current age. The analysis of EPSy identified three main factors, namely mistrust/paranoia, perceptual aberrations/hallucinations and disorganized symptoms. It has good psychometric properties. Data also shows that, independently of the participant's age, the total score on the 2-years-old version predicts the total score on the current-age version, and this is also the case for each individual factor. Finally, it is of clinical interest since it makes it possible to describe symptomatology both at age 2 and at the child's present age depending on the group to which the children are assigned (control children, psychotic children, non-psychotic children).

Electroconvulsive therapy or clozapine for adolescents with treatment-resistant schizophrenia: an explorative analysis on symptom dimensions

OBJECTIVE

This study sought to compare pre-intervention patient characteristics and post-intervention outcomes in a naturalistic sample of adolescent inpatients with treatment-resistant psychotic symptoms who received either electroconvulsive therapy (ECT) or clozapine.

METHODS

Data of adolescents with schizophrenia/schizoaffective disorder receiving ECT or clozapine were retrospectively collected from two tertiary-care psychiatry-teaching university hospitals. Subscale scores of the Positive and Negative Symptom Scale (PANSS) factors were calculated according to the five-factor solution. Baseline demographics, illness characteristics, and post-intervention outcomes were compared.

RESULTS

There was no significant difference between patients receiving ECT (n = 13) and clozapine (n = 66) in terms of age, sex, and the duration of hospital stay. The ECT group more commonly had higher overall illness and aggression severity. Smoking was less frequent in the clozapine group. Baseline resistance/excitement symptom severity was significantly higher in the ECT group, while positive, negative, affect, disorganisation, and total symptom scores were not. Both interventions provided a significant reduction in PANSS scores with large effect sizes.

CONCLUSION

Both ECT and clozapine yielded high effectiveness rates in adolescents with treatment-resistant schizophrenia/schizoaffective disorder. Youth receiving ECT were generally more activated than those who received clozapine.

Lost in Translation: Challenges in the Diagnosis and Treatment of Early-Onset Schizophrenia

Early-onset schizophrenia (EOS) is a heterogeneous condition that has a serious, insidious clinical course and poor long-term mental health outcomes. The clinical presentations are highly complex due to the overlapping symptomatology with other illnesses, which contributes to a delay in the diagnosis. The objective of the review is to study if an earlier age of onset (AAO) of EOS has poor clinical outcomes, the diagnostic challenges of EOS, and effective treatment strategies. The review provides a comprehensive literature search of 5966 articles and summarizes 126 selected for empirical evidence to methodically consider challenges in diagnosing and treating EOS for practicing clinicians. The risk factors of EOS are unique but have been shared with many other neuropsychiatric illnesses. Most of the risk factors, including genetics and obstetric complications, are nonmodifiable. The role of early diagnosis in reducing the duration of untreated psychosis (DUP) remains critical to reducing overall morbidity. Many specific issues contribute to the risk and clinical outcomes. Therefore, issues around diagnostic ambiguity, treatment resistance, nonadherence, and rehospitalizations further extend the DUP. There is hesitancy to initiate clozapine early, even though the empirical evidence strongly supports its use. There is a growing body of research that suggests the use of long-acting injectables to address nonadherence, and these measures are largely underutilized in acute settings. The clinical presentations of EOS are complex. In addition to the presence of specific risk factors, patients with an early onset of illness are also at a higher risk for treatment resistance. While there is a need to develop tools for early diagnosis, established evidence-based measures to address nonadherence, psychoeducation, and resistance must be incorporated into the treatment planning.

Low Dose Clozapine in Early Onset Resistant Schizophrenia: Case Report and Two Year Follow-up

Childhood-onset schizophrenia (COS) is considered a rare and severe form of schizophrenia, with onset before age 13 and only half of affected patients responding to nonclozapine antipsychotics.¹ These patients with resistant COS show favorable responses to clozapine, but with higher adverse effects than seen in adults. Some resistant cases respond at a lower dose with minimal adverse effects.² However, it is unclear which patients will respond to a low dose and how long one should wait before increasing the dose of clozapine. We report a patient with resistant COS who showed a favorable but delayed-onset response to low-dose clozapine.

Regional clozapine, ECT and lithium usage inversely associated with excess suicide rates in male adolescents

Advanced psychiatric treatments remain uncertain in preventing suicide among adolescents. Across the 21 Swedish regions, using nationwide registers between 2016-2020, we found negative correlation between adolescent excess suicide mortality (AESM) and regional frequencies of clozapine, ECT, and lithium (CEL) usage among adolescents (β = -0.613, p = 0.0003, 95% CI: -0.338, -0.889) and males (β = -0.404, p = 0.009, 95% CI: -0.130, -0.678). No correlation was found among females (p = 0.197). Highest CEL usage among male adolescents was seen in regions with lowest quartile (Q1) AESM (W = 74, p = 0.012). Regional CEL treatment frequency in 15-19-year-olds was related to lower AESM in males, reflecting potential treatment efficacy, treatment compliance or better-quality mental health care. Suicide prevention may benefit from early recognition and CEL treatment for severe mental illness in male adolescents. The results indicate association but further research, using independent samples and both prospective and observational methodologies, is needed to confirm causality.

Approach to New-Onset Psychosis in Pediatrics: A Review of Current Practice and an Interdisciplinary Consensus-Driven Clinical Pathway at a Single-Center Institution

New-onset psychosis in the pediatric population poses many diagnostic challenges. Given the diversity of underlying causes, which fall under the purview of multiple medical specialties, a timely, targeted, yet thorough workup requires a systematic and coordinated approach. A committee of expert pediatric physicians from the divisions of emergency medicine, psychiatry, neurology, hospitalist medicine, and radiology convened to create and implement a novel clinical pathway and approach to the pediatric patient presenting with new-onset psychosis. Here we provide background and review the evidence supporting the investigations recommended in our pathway to screen for a comprehensive range of etiologies of pediatric psychosis.

Clozapine for Management of Childhood and Adolescent-Onset Schizophrenia: A Systematic Review and Meta-Analysis

Background: Schizophrenia at a young age deserves investigation because of the greater severity and burden of illness on individuals and health care than its adult onset. For this study, we included both childhood-onset schizophrenia and early-onset schizophrenia. We used the common term "childhood and adolescent-onset schizophrenia (CAOS)" for either type. This systematic review provides an overview of the clinical use, efficacy, and safety of clozapine treatment in managing CAOS. Methods: We conducted a systematic literature search in PubMed, Embase, and PsycINFO databases. We searched for randomized controlled trials (RCTs), open-label studies (OLSs), review articles, meta-analytic and observational studies. Our literature search resulted in 1242 search results. After the title, abstract, and full article review, 18 studies qualified (double-blind RCTs n = 4; OLS n = 4; observational studies n = 7; case reports n = 3). Results: Clozapine use in CAOS was generally well tolerated and not associated with any fatalities. Clozapine use in the short term (6 weeks) and long term (2-9 years) was superior in efficacy than other antipsychotics in CAOS management. Improvement in overall symptoms was maintained during long-term follow-up over the years in OLSs. Clozapine appeared to have a favorable clinical response and shorter hospital stays. Sedation and hypersalivation were commonly reported (90%), constipation was next in frequency (13%-50%). Neutropenia was seen in 6%-15% of cases and agranulocytosis (<0.1%). Although weight gain was common (up to 64%), followed by metabolic changes (8%-22%), treatment-onset diabetes was less frequent (<6%). Akathisia, tachycardia, and blood pressure changes were less commonly seen. Conclusions: Limited studies indicate that clozapine is a safe and efficacious option for CAOS management. We need large-scale and well-designed long-term RCTs for the use of clozapine in the management of CAOS.

Treatment Approaches for First Episode and Early-Phase Schizophrenia in Adolescents and Young Adults: A Delphi Consensus Report from Europe

PURPOSE

Although first-episode psychosis (FEP) in youth, particularly early-onset schizophrenia (EOS), is managed similarly to adult-onset schizophrenia, few antipsychotics are approved for people aged 13-18 years. We aimed to explore areas of uncertainty in EOS management and provide evidence-based recommendations to mental health specialists. We used the Delphi methodology to gain knowledge in areas lacking evidence-based strategies. This standardized methodology consists of the development of a questionnaire by content experts, which is then submitted to a broader panel of professionals (panelists) to survey their level of agreement on the topics proposed.

MATERIALS AND METHODS

The developed questionnaire covered patient management from diagnosis to maintenance treatment and was administered to a broader panel of specialists across Europe. Based on an analysis of responses received in this first round, the items that needed further insight were submitted to the panel for a second round and then reanalysed.

RESULTS

An initial set of 90 items was developed; in round I, consensus was reached for 83/90 items (92%), while it was reached for 7/11 (64%) of the items sent out for rerating in round II. Feedback for rounds I and II was obtained from 54/92 and 48/54 approached experts, respectively. There was broad agreement on diagnostic standards, multimodal approaches and focus on adverse events, but uncertainty in terms of pharmacological strategies (including clozapine) in case of failure and antipsychotic dosing in younger patients.

CONCLUSION

Despite knowledge about diagnostic clues and integrated management of EOS, this study highlights the lack of standardization in treating EOS, with safety arguments having a major role in the decision-making process. Targeted clinical trials and systematic dissemination across Europe of current scientific evidence on the value of early intervention services is hoped to contribute to standardized and improved quality care for patients with early-phase psychosis and schizophrenia.

Investigating Predictors of Clozapine Response in Adolescents with Schizophrenia and Schizoaffective Disorder

Objectives: We aimed to determine the clinical predictors of clozapine response in patients with early-onset schizophrenia (EOS)/schizoaffective disorder and the effect of substance use disorder (SUD) on treatment outcomes. Methods: Medical records of patients with treatment-resistant EOS receiving clozapine were identified for data analysis dated between January 2015 and April 2020. Patients on clozapine were followed in an inpatient unit of a tertiary care mental health hospital. Using the Positive and Negative Symptom Scale (PANSS), ≥30% reduction was defined as the response criteria after clozapine treatment. Results: Of 50 subjects (age: 16.3 ± 1.3 years, 36.0% female), 22 subjects (44.0%) met the defined response criteria. Clozapine responder (CLZ-R) and clozapine nonresponder (CLZ-NR) groups were similar regarding age at illness onset, sex, and duration of untreated psychosis. The CLZ-R group had higher baseline positive PANSS scores (24.8 ± 8.1 vs. 17.1 ± 6.6, p = 0.001, d = 1.0) and total PANSS scores (94.8 ± 17.2 vs. 80.1 ± 19.8, p = 0.008, d = 0.8) compared with the CLZ-NR counterparts. The duration of hospital stay was longer in the CLZ-NR group (122.3 ± 48.2 vs. 87.3 ± 36.2 days, p = 0.007). Among 32 male patients, the presence of SUD (n = 9, 28.1%) was associated with a less reduction in total PANSS scores (F = 7.5, p = 0.010) and higher levels of positive symptoms at the end of the treatment (12.8 ± 4.1 vs. 18.8 ± 7.4, p = 0.006, d = 1.0). Synthetic cannabinoids were the most common substance type used among males with treatment-refractory EOS (25.0%). Conclusions: Our results did not support the role of sociodemographic variables in clozapine response. Positive symptoms and SUD yielded a prognostic value in patients receiving clozapine.

Decision making under ambiguity and risk in adolescent-onset schizophrenia

OBJECTIVE

Numerous studies have identified impaired decision making (DM) under both ambiguity and risk in adult patients with schizophrenia. However, the assessment of DM in patients with adolescent-onset schizophrenia (AOS) has been challenging as a result of the instability and heterogeneity of manifestations. The Iowa Gambling Task (IGT) and Game of Dice Task (GDT), which are frequently used to evaluate DM respectively under ambiguity and risk, are sensitive to adolescents and neuropsychiatric patients. Our research intended to examine the performance of DM in a relatively large sample of patients with AOS using the above-mentioned two tasks. We also aimed to take a closer look at the relationship between DM and symptom severity of schizophrenia.

METHODS

We compared the performance of DM in 71 patients with AOS and 53 well-matched healthy controls using IGT for DM under ambiguity and GDT for DM under risk through net scores, total scores and feedback ration. Neuropsychological tests were conducted in all participants. Clinical symptoms were evaluated by using Positive and Negative Syndrome Scale (PANSS) in 71 patients with AOS. Pearson's correlation revealed the relationship among total score of DM and clinical and neuropsychological data.

RESULTS

Compared to healthy controls, patients with AOS failed to show learning effect and had a significant difference on the 5th block in IGT and conducted more disadvantageous choices as well as exhibited worse negative feedback rate in GDT. Apart from DM impairment under risk, diminished DM abilities under ambiguity were found related to poor executive function in AOS in the present study.

CONCLUSIONS

Our findings unveiled the abnormal pattern of DM in AOS, mainly reflected under the risky condition, extending the knowledge on the performance of DM under ambiguity and risk in AOS. Inefficient DM under risk may account for the lagging impulse control and the combined effects of developmental disease. In addition, our study demonstrated that the performance on IGT was related to executive function in AOS.

Interest of Fluvoxamine as an Add-On to Clozapine in Children With Severe Psychiatric Disorder According to CYP Polymorphisms: Experience From a Case Series

Despite its drastic efficacy in resistant psychiatric disorders, clozapine remains rarely used in youth due to its side effects. Clozapine plasma level is determined through its metabolism involving several isoforms of cytochromes 450 (CYP450) family. Isoform CYP1A2 appears as a limiting enzyme involved in the metabolism of clozapine, while isoforms 2C19, 2D6, 3A4, and 3A5 also contribute in a minor way. Clozapine efficacy is limited by a significant inter-patient variability in exposure according to CYP's polymorphisms. Clozapine plasma levels may be increased with CYP inhibitors such as fluvoxamine. This drug is a potent enzymatic inhibitor of CYP1A2 and, to a lesser extent, of CYP3A4 and CYP2D6. Hence, in case of CYP's polymorphisms in youth, the use of fluvoxamine as add-on to clozapine could help in reaching clinical and biological efficacy and allowing lower clozapine dosage and a better tolerance profile as it has already been described in adults. We report four pediatric cases with severe psychiatric disorders underlying our experience with CYP polymorphism explorations and the use of fluvoxamine as add-on to clozapine. Our four patients clinically improved after the introduction of fluvoxamine, enhancing clozapine metabolism and therefore the clozapine plasma level within therapeutic range. Despite the interesting results of fluvoxamine, we report a severe issue of tolerance for one patient, emphasizing the need for caution regarding possible drug interactions when fluvoxamine is considered. Hence, we propose a detailed step-by-step multidisciplinary protocol.

Predictors of outcome in early onset schizophrenia: a 10-year follow-up study

BACKGROUND

Younger age at onset is generally thought to be a predictor of poor outcome in Early Onset Schizophrenia (EOS), but there is a paucity of epidemiological data supporting this belief. This study aims to describe long-term outcomes and predictors of patient functioning in EOS, with a focus on the effect of age at onset.

METHODS

We consecutively enrolled 118 EOS patients who were hospitalized in 2006. Mean age at baseline was 13.3 ± 2.3 years. Sixty-five subjects were successfully interviewed. Mean length of follow up was 10.4 ± 0.3 years. Baseline data were collected from inpatient medical records, while follow up was conducted primarily through telephone interviews of patient relatives. WHODAS 2.0 was used to measure global functioning at follow up. Outcomes included education, employment, marriage status, physical health, subsequent diagnoses and treatment, and patient functioning. Univariate and multivariate regression models were used to assess predictors of outcome, while propensity scores were used to adjust for confounding in analyzing the effect of age at onset on functional outcome.

RESULTS

Of the 65 subjects where follow-up data were available, 3 were deceased at follow up. Five (8%) discontinued treatment. Diagnostic stability was 76%. Nearly a quarter (24%) were using clozapine at follow up. In male and female patients, 61 and 55% respectively were overweight, while 29 and 32% respectively were obese. Sixteen (26%) were economically self-sufficient, while 34 (55%) were unemployed. Thirteen (21%) patients had ever been married. The median WHODAS score was 15 (IQR 2 to 35), roughly corresponding to the 78th percentile on population norms. Extroverted personality (p = 0.01), suspicious personality (p = 0.02), and high level of education (p = 0.001) predicted better functioning. Age of onset was not associated with function in either the univariate model (p = 0.24), full model (p = 0.17) or the final risk factor model (p = 0.11), nor after using propensity scores to further adjust for confounders.

CONCLUSION

The long-term functional outcome of EOS is more optimistic than generally believed. Age at disease onset does not predict long-term functional outcome in EOS populations.

Developmental and symptom profiles in early-onset psychosis

Psychotic disorders in children are more heterogeneous than is captured by categorical diagnoses. In a new cohort of children and adolescents, we evaluated the relationships among age at onset (AAO), clinical symptoms and developmental impairments. Patients with schizophrenia and other "spectrum" psychotic diagnoses (N = 88; AAO 6-17, mean 12.6) were evaluated with diagnostic interviews, a new clinical scale (Lifetime Dimensions of Psychosis Scale-Child and Adolescent), and neuropsychological and medical evaluations. Key findings were replicated in an adult cohort of 2420 cases, including 127 with retrospective AAO<13. Factor and cluster analyses were carried out to identify clinical profiles. Five clinical factors were identified in each cohort: Positive, Bizarre Positive, Negative/Formal Thought Disorder, Depression and Mania. Earlier AAO predicted severity of bizarre positive symptoms in children and of bizarre and other symptoms in adults. Four clinical clusters in the child cohort were characterized by: more severe bizarre positive symptoms (N = 31); negative symptoms (N = 15); premorbid autism spectrum features and developmental delay (N = 12); and depressive symptoms with heterogeneous diagnoses and mild positive/negative symptoms (N = 25). Previous factor-analytic studies of childhood psychosis did not specifically consider bizarre positive symptoms. Here, bizarre positive symptoms emerged as clinical markers of severe, childhood-onset psychosis similar to adult schizophrenia. The four clusters are clinically meaningful and useful for treatment planning and potentially for biological research. Childhood-onset cases are rare and thus difficult to study, but additional, larger cohorts may be useful in dissecting the biological and developmental heterogeneity of psychotic disorders.

Delays and barriers to the commencement of clozapine in eligible people with a psychotic disorder: A literature review

AIM

While the majority of individuals with a first episode of psychosis (FEP) achieve symptomatic remission with the appropriate treatment, there is a small but significant proportion who do not achieve remission of symptoms despite adequate treatment with at least two antipsychotic medications (termed treatment resistance). Clozapine is indicated in individuals who fulfil the criteria for treatment-resistant schizophrenia, however, despite it being the most effective antipsychotic medication, there can be delays in the commencement of clozapine in eligible patients.

METHODS

A systematic search was performed to identify articles reporting either the time taken to commence clozapine (or delays) in eligible individuals or articles reporting barriers to the commencement of clozapine. The initial search generated 5588 articles and of these, 18 were eligible.

RESULTS

13 studies described delays in commencing clozapine and five studies reported on the barriers to the commencement of clozapine. The duration of delay from when an individual was deemed eligible for clozapine treatment to the time of clozapine commencement ranged from 19.3 weeks to 5.5 years. In addition, the duration of illness prior to clozapine initiation ranged from 1.1 to 9.7 years. It was found that some clinicians were more inclined to prescribe antipsychotic polypharmacy or doses higher than recommended than to prescribe clozapine.

CONCLUSIONS

Delays in commencing clozapine have been consistently demonstrated. Early intervention for psychosis services are the ideal settings to identify individuals with persistent positive psychotic symptoms and commence clozapine if indicated.

Negative Symptoms in Early-Onset Psychosis and Their Association With Antipsychotic Treatment Failure

The prevalence of negative symptoms (NS) at first episode of early-onset psychosis (EOP), and their effect on psychosis prognosis is unclear. In a sample of 638 children with EOP (aged 10-17 y, 51% male), we assessed (1) the prevalence of NS at first presentation to mental health services and (2) whether NS predicted eventual development of multiple treatment failure (MTF) prior to the age of 18 (defined by initiation of a third trial of novel antipsychotic due to prior insufficient response, intolerable adverse-effects or non-adherence). Data were extracted from the electronic health records held by child inpatient and community-based services in South London, United Kingdom. Natural Language Processing tools were used to measure the presence of Marder Factor NS and antipsychotic use. The association between presenting with ≥2 NS and the development of MTF over a 5-year period was modeled using Cox regression. Out of the 638 children, 37.5% showed ≥2 NS at first presentation, and 124 (19.3%) developed MTF prior to the age of 18. The presence of NS at first episode was significantly associated with MTF (adjusted hazard ratio 1.62, 95% CI 1.07-2.46; P = .02) after controlling for a number of potential confounders including psychosis diagnostic classification, positive symptoms, comorbid depression, and family history of psychosis. Other factors associated with MTF included comorbid autism spectrum disorder, older age at first presentation, Black ethnicity, and family history of psychosis. In EOP, NS at first episode are prevalent and may help identify a subset of children at higher risk of responding poorly to antipsychotics.

A Retrospective Multicenter Evaluation of Clozapine Use in Pediatric Patients Admitted for Acute Psychiatric Hospitalization

OBJECTIVES

Clozapine is the drug of choice for treatment-resistant schizophrenia. While pediatric clozapine use is not contraindicated, the literature describing its clinical application is limited. The primary objective of this study was to assess the use of clozapine in a child and adolescent population by characterizing the documented safety and clinical benefits of the medication.

METHODS

A multicenter retrospective study at sites in the United States and Australia included children and adolescents admitted to a psychiatric unit who were administered at least one dose of clozapine. Information related to demographics, patient history, past treatments, clozapine, and adverse events was collected.

RESULTS

Eighty-two patients from eight sites were included in this study. Patients were predominantly clozapine naive (76.8%), and most had a discharge diagnosis of a primary psychotic disorder (61%) or bipolar disorder (25.6%). Four clozapine discontinuations occurred during hospitalization due to severe neutropenia, ileus, need for diagnostic clarification, and significant psychomotor retardation. The remainder (n = 78) were discharged on a mean clozapine dose of 218.1 ± 142.2 mg. Sedation (26.8%) and sialorrhea (17.1%) were the most common documented adverse events. The mean number of previously trialed antipsychotics before clozapine was 3.5 ± 1.4 (range 1-10). Improvement with clozapine was documented as significant (31.7%), moderate (32.9%), minimal (12.2%), no improvement (2.4%), and not described (20.7%).

CONCLUSIONS

In this cohort, 95% of pediatric patients admitted with or started on clozapine during an acute psychiatric hospitalization were discharged on the medication. The high incidence of adverse events should reinforce to clinicians the need for vigilant monitoring. Pediatric guidelines recommend clozapine for refractory schizophrenia but stress the critical need to ensure an accurate diagnosis. Limited data exist for the use of clozapine in pediatric patients with other diagnoses.

Clozapine-induced myocarditis in an adolescent male with DiGeorge Syndrome

DiGeorge Syndrome (22q11.2 deletion syndrome) is a chromosomal disorder associated with both congenital heart malformations and schizophrenia, which is often treatment-resistant and may warrant treatment with clozapine. Clozapine-induced myocarditis (CIM) is a rare complication of clozapine therapy, with a reported incidence ranging from 0.015% to 3%. Fulminant CIM has a nonspecific presentation in both adult and pediatric populations and a mortality rate approaching 50%. Few cases of pediatric CIM have been documented in the literature. This report highlights a case of CIM in an adolescent male with DiGeorge Syndrome whose clinical course was characterized by a subtle, nonspecific presentation and resolution with supportive care.

Dilemmas in the treatment of early-onset first-episode psychosis

Early-onset first-episode psychosis (EOP) is a severe mental disorder that can pose a number of challenges to clinicians, young people and their families. Its assessment and differentiation from other neurodevelopmental and mental health conditions may at times be difficult, its treatment may not always lead to optimal outcomes and can be associated with significant side effects, and its long-term course and prognosis seem to be less favourable compared with the adult-onset disorder. In this paper, we discuss some dilemmas associated with the evaluation and management of EOP and propose approaches that can be used in the clinical decision-making process. A detailed and well-informed assessment of psychotic symptoms and comorbidities, a systematic approach to treatment with minimum possible medication doses and close monitoring of its effectiveness and adverse effects, and multidimensional interventions taking into consideration risks and expectations associated with EOP, are paramount in the achievement of the most favourable outcomes for affected children and young people.

Autism spectrum disorder and schizophrenia: boundaries and uncertainties

Autism and schizophrenia were placed in different diagnostic categories in DSM-III, having previously been considered as related diagnostic entities. New evidence suggests that these disorders show clinical and cognitive deficit overlaps and shared neurobiological characteristics. Furthermore, children presenting with both autism spectrum disorder (ASD) and psychotic experiences may represent a subgroup of ASD more closely linked to psychosis. The study of ASD and childhood schizophrenia, and their clinical boundaries and overlapping pathophysiological characteristics, may clarify their relationship and lead to more effective interventions. This article discusses the relationship through a critical review of current and historical dilemmas surrounding the phenomenology and pathophysiology of these disorders. It provides a framework for working with children and young people with mixed clinical presentations, illustrated by three brief fictional case vignettes.

Polygenic Risk Score for Schizophrenia and Treatment-Resistant Schizophrenia

Treatment-resistant schizophrenia (TRS) affects around one-third of individuals with schizophrenia. Although a number of sociodemographic and clinical predictors of TRS have been identified, data on the genetic risk of TRS are sparse. We aimed to investigate the association between a polygenic risk score for schizophrenia and treatment resistance in patients with schizophrenia. We conducted a nationwide, population-based follow-up study among all Danish individuals born after 1981 and with an incident diagnosis of schizophrenia between 1999 and 2007. Based on genome-wide data polygenic risk scores for schizophrenia were calculated in 862 individuals with schizophrenia. TRS was defined as either clozapine initiation or at least 2 periods of different antipsychotic monotherapies and still being hospitalized. We estimated hazard rate ratios (HRs) for TRS in relation to the polygenic risk score while adjusting for population stratification, age, sex, geographical area at birth, clinical treatment setting, psychiatric comorbidity, and calendar year. Among the 862 individuals with schizophrenia, 181 (21.0%) met criteria for TRS during 4674 person-years of follow-up. We found no significant association between the polygenic risk score and TRS, adjusted HR = 1.13 (95% CI: 0.95-1.35). Based on these results, the use of the polygenic risk score for schizophrenia to identify individuals with TRS is at present inadequate to be of clinical utility at the individual patient level. Future research should include larger genetic samples in combination with non-genetic markers. Moreover, a TRS-specific developed polygenic risk score would be of great interest towards early prediction of TRS.

International trends in clozapine use: a study in 17 countries

OBJECTIVE

There is some evidence that clozapine is significantly underutilised. Also, clozapine use is thought to vary by country, but so far no international study has assessed trends in clozapine prescribing. Therefore, this study aimed to assess clozapine use trends on an international scale, using standardised criteria for data analysis.

METHOD

A repeated cross-sectional design was applied to data extracts (2005-2014) from 17 countries worldwide.

RESULTS

In 2014, overall clozapine use prevalence was greatest in Finland (189.2/100 000 persons) and in New Zealand (116.3/100 000), and lowest in the Japanese cohort (0.6/100 000), and in the privately insured US cohort (14.0/100 000). From 2005 to 2014, clozapine use increased in almost all studied countries (relative increase: 7.8-197.2%). In most countries, clozapine use was highest in 40-59-year-olds (range: 0.6/100 000 (Japan) to 344.8/100 000 (Finland)). In youths (10-19 years), clozapine use was highest in Finland (24.7/100 000) and in the publicly insured US cohort (15.5/100 000).

CONCLUSION

While clozapine use has increased in most studied countries over recent years, clozapine is still underutilised in many countries, with clozapine utilisation patterns differing significantly between countries. Future research should address the implementation of interventions designed to facilitate increased clozapine utilisation.

The Association Between Comorbid Autism Spectrum Disorders and Antipsychotic Treatment Failure in Early-Onset Psychosis: A Historical Cohort Study Using Electronic Health Records

OBJECTIVE

In a sample of children and adolescents with first-episode psychosis, we investigated whether multiple treatment failure (MTF, defined as the initiation of a third trial of novel antipsychotic due to nonadherence, adverse effects, or insufficient response) was associated with comorbid autism spectrum disorders.

METHODS

Data were from the electronic health records of 638 children (51% male) aged from 10 to 17 years with first-episode psychosis (per ICD-10 criteria) from January 1, 2008, to November 1, 2014, referred to mental health services in South London, United Kingdom; data were extracted using the Clinical Record Interactive Search (CRIS) system. The effect of autism spectrum disorder comorbidity on the development of MTF during a 5-year period was modeled using Cox regression.

RESULTS

There were 124 cases of MTF prior to the age of 18 (19.4% of the sample). Comorbid autism spectrum disorders were significantly associated with MTF (adjusted hazard ratio = 1.99; 95% CI, 1.19-3.31; P = .008) after controlling for a range of potential confounders. Other factors significantly associated with MTF included higher age at first presentation (P = .001), black ethnicity (P = .03), and frequency of clinical contact (P < .001). No significant association between other comorbid neurodevelopmental disorders (hyperkinetic disorder or intellectual disability) and MTF was found.

CONCLUSIONS

Children with first-episode psychosis and comorbid autism spectrum disorders at first presentation are less likely to have a beneficial response to antipsychotics.

Factors associated with readmission in South African adolescents discharged from two inpatient psychosocial rehabilitation units

OBJECTIVE

This study aimed to describe the socio-demographic and clinical factors associated with readmission in an adolescent population discharged from two inpatient psychosocial rehabilitation (PSR) units in Cape Town, South Africa.

METHOD

Data were obtained from 97 consecutive patients discharged from two adolescent psychiatric PSR units over a period of one year. Patients were followed up for readmission to hospitals offering specialised psychiatric care in the Western Cape Province over a period of 18 months.

RESULTS

35 patients (36%) were readmitted during the study period. Multivariable analysis showed that previous admission increased readmission rate (Incidence Rate Ratio (IRR): 8.01, p < 0.001). Adolescents who were still schooling (IRR: 0.29, p < 0.001) or had a higher level of education (IRR: 0.45, p = 0.001) were less likely to be readmitted. No association was seen with type of diagnosis and readmission, although 51 adolescents (53%) were diagnosed on the schizophrenia spectrum of disorders.

CONCLUSION

Study findings highlight the need for increased collaboration between the Departments of Health and Education. Furthermore, the study illustrates the need for specific post-discharge community follow-up for adolescents. Prospective research in this particular population group is needed to contribute to the literature on factors associated with readmission in South African adolescent patients.

Two distinct patterns of treatment resistance: clinical predictors of treatment resistance in first-episode schizophrenia spectrum psychoses

BACKGROUND

Clozapine remains the only evidence-based antipsychotic for treatment-resistant schizophrenia (TRS). The ability to predict which patients with their first onset of schizophrenia would subsequently meet criteria for treatment resistance (TR) could help to diminish the severe functional disability which may ensue if TR is not recognized and correctly treated.

METHOD

This is a 5-year longitudinal assessment of clinical outcomes in a cohort of 246 first-episode schizophrenia spectrum patients recruited as part of the NIHR Genetics and Psychosis (GAP) study conducted in South London from 2005 to 2010. We examined the relationship between baseline demographic and clinical measures and the emergence of TR. TR status was determined from a review of electronic case records. We assessed for associations with early-, and late-onset TR, and non-TR, and differences between those TR patients treated with clozapine and those who were not.

RESULTS

Seventy per cent (n = 56) of TR patients, and 23% of the total study population (n = 246) were treatment resistant from illness onset. Those who met criteria for TR during the first 5 years of illness were more likely to have an early age of first contact for psychosis (<20 years) [odds ratio (OR) 2.49, 95% confidence interval (CI) 1.25-4.94] compared to those with non-TR. The relationship between an early age of first contact (<20 years) and TR was significant in patients of Black ethnicity (OR 3.71, 95% CI 1.44-9.56); and patients of male gender (OR 3.13 95% CI 1.35-7.23).

CONCLUSIONS

For the majority of the TR group, antipsychotic TR is present from illness onset, necessitating increased consideration for the earlier use of clozapine.

Strong Treatment Response and High Maintenance Rates of Clozapine in Childhood-Onset Schizophrenia

OBJECTIVE

Childhood-onset schizophrenia (COS) is a rare but severe form of the disorder, which is often treatment refractory. Short-term studies have indicated a greater differential efficacy, evident through effect sizes, favoring clozapine over other agents in alleviating negative symptoms in COS patients compared with adult-onset patients (AOS). There have been no data for COS patients on long-term compliance with clozapine treatment. Therefore, we wanted to know, over a span of up to 24 years, how many of our COS cohort had remained on clozapine for at least 2 years. We review short-term treatment data and present updated long-term data on compliance and functioning for our patients.

METHODS

We present the results for long-term medication maintenance over a 24 year observation period for our cohort of 131 patients. Of this cohort, 91.6% (120) were available for follow-up information from either in-person or telephone contact with the patient and/or family members. We defined clozapine compliance as ≥2 years receiving this medication and doing well.

RESULTS

We were able to contact 120 of the 131 patients. In spite of the additional cost and inconvenience of regular blood monitoring, 87 patients (72.5%, 87/120) adhered to long-term clozapine maintenance therapy with dosages ranging from 50 to 900 mg, and a median dosage of 500 mg. This rate exceeds the long-term clozapine maintenance rates reported for AOS patients.

CONCLUSIONS

Short-term data on differential efficacy and long-term maintenance data suggest a possibly greater efficacy of clozapine, relative to other antipsychotics, in COS than in AOS. Our overall findings indicate that very early-onset schizophrenic patients may be more responsive to clozapine. This extends other support for clozapine as an option in the treatment of early-onset schizophrenia.

Predictors of treatment resistance in patients with schizophrenia: a population-based cohort study

BACKGROUND

Identification of patients at high risk of treatment-resistant schizophrenia at the time of schizophrenia diagnosis would be of great clinical benefit in minimising the delay to clozapine treatment in patients unlikely to respond to non-clozapine antipsychotics. However, little is known about predictors of treatment resistance in this patient population. We used a treatment-based proxy for treatment-resistant schizophrenia to identify candidate predictors of treatment resistance at first hospital contact with a schizophrenia diagnosis.

METHODS

In this population-based cohort study, we obtained Danish national registry data for all adult patients (≥18 years) with incident schizophrenia diagnosed between Jan 1, 1996, and Dec 31, 2006, and followed up until Dec 31, 2010. Our main proxy definition of treatment-resistant schizophrenia was the earliest instance of either clozapine initiation or hospital admission for schizophrenia after having had two periods of different antipsychotic monotherapy. We did multivariable Cox proportional hazards regression analysis to estimate the association between baseline candidate predictors and treatment resistance.

FINDINGS

8624 patients fulfilled the criteria for inclusion. In multivariable complete-case analyses, 1703 (21%) of 8044 patients fulfilled the main proxy definition of treatment-resistant schizophrenia during a median follow-up of 9·1 years (IQR 6·3-11·9). Younger age (hazard ratio 0·96 [95% CI 0·95-0·97]), living in a less urban area (provincial 1·38 [1·23-1·56], rural 1·44 [1·25-1·65]), primary education level (0·88 [0·79-0·98]), more than 30 bed-days in psychiatric hospital in the year before first schizophrenia diagnosis (1·54 [1·35-1·75]), inpatient at first schizophrenia diagnosis (2·07 [1·87-2·29]), paranoid subtype (1·24 [1·13-1·37]), comorbid personality disorder (1·24 [1·11-1·39]), psychotropic drug use (antipsychotics 1·51 [1·35-1·69], antidepressants 1·15 [1·03-1·29], and benzodiazepines 1·22 [1·10-1·37]), and previous suicide attempt (1·21 [1·07-1·39]) were all significantly associated with treatment-resistant schizophrenia.

INTERPRETATION

Our study identifies several candidate predictors that could potentially be included in future prediction models for treatment-resistant schizophrenia. Notably, established risk factors for schizophrenia did not predict treatment resistance, suggesting that treatment-resistant disease might be a distinct subtype of schizophrenia and not merely a more severe form.

FUNDING

European Community's Seventh Framework Programme.