Antipsychotic polypharmacy and augmentation strategies prior to clozapine initiation: a historical cohort study of 310 adults with treatment-resistant schizophrenic disorders

Using a statistical learning approach to identify sociodemographic and clinical predictors of response to clozapine

BACKGROUND

A proportion of people with treatment-resistant schizophrenia fail to show improvement on clozapine treatment. Knowledge of the sociodemographic and clinical factors predicting clozapine response may be useful in developing personalised approaches to treatment.

METHODS

This retrospective cohort study used data from the electronic health records of the South London and Maudsley (SLaM) hospital between 2007 and 2011. Using the Least Absolute Shrinkage and Selection Operator (LASSO) regression statistical learning approach, we examined 35 sociodemographic and clinical factors' predictive ability of response to clozapine at 3 months of treatment. Response was assessed by the level of change in the severity of the symptoms using the Clinical Global Impression (CGI) scale.

RESULTS

We identified 242 service-users with a treatment-resistant psychotic disorder who had their first trial of clozapine and continued the treatment for at least 3 months. The LASSO regression identified three predictors of response to clozapine: higher severity of illness at baseline, female gender and having a comorbid mood disorder. These factors are estimated to explain 18% of the variance in clozapine response. The model's optimism-corrected calibration slope was 1.37, suggesting that the model will underfit when applied to new data.

CONCLUSIONS

These findings suggest that women, people with a comorbid mood disorder and those who are most ill at baseline respond better to clozapine. However, the accuracy of the internally validated and recalibrated model was low. Therefore, future research should indicate whether a prediction model developed by including routinely collected data, in combination with biological information, presents adequate predictive ability to be applied in clinical settings.

Combination Therapy of Long-Acting Injectable Second-Generation Antipsychotics and Oral Antipsychotics: A Retrospective Chart Review and Prescribers' Attitude Survey

BACKGROUND

Although long-acting injectable antipsychotics (LAI-APs) have been considered as a monotherapeutic option in the maintenance treatment of schizophrenia, it has been recently reported that the combination therapy of LAI-APs and oral antipsychotics (OAPs) is common.

METHODS

We conducted a retrospective chart review to examine the situation of the combination therapy of LAI second-generation antipsychotics (LAI-SGAs) and OAPs, and a questionnaire survey to investigate prescribers' attitudes toward the combination therapy. We included patients who received any LAI-SGAs for 1 month or longer and classified them into monotherapy and combination therapy groups. We collected information on age, sex, primary psychiatric diagnosis, and concomitant psychotropic medications.

RESULTS

Of the 132 patients, 39 (29.5%) received the combination therapy of LAI-SGAs and OAPs. Long-acting injectable risperidone was significantly associated with receiving the combination therapy compared with LAI aripiprazole. Olanzapine was the most common OAP in combination with LAI-SGAs. Only 8 patients (20.5%) concurrently received the same type of OAPs as LAI-SGAs. More than 60% of the patients received OAP polypharmacy before the initiation of LAI-SGAs. The psychiatrists in charge prescribed LAI-SGAs mainly because of a concern about adherence, and OAPs mainly because of insufficient dose of LAI-SGAs, to patients in the combination therapy group. They estimated that adherence to OAPs in two thirds of the patients in the combination therapy group was 80% or higher.

CONCLUSIONS

The present study showed that the combination therapy of LAI-SGAs and OAPs is often conducted in real-world clinical practice. Considering the reason for the introduction of LAI-APs, clinicians should carefully monitor patients' adherence to OAPs concurrently used with LAI-APs.

Early access to clozapine in Early Intervention in Psychosis: Hope vs reality. A mixed method service analysis

AIM

Improving access to clozapine is a recognized priority nationally across Early Intervention in Psychosis Services (EIPS) in the UK. Treatment resistance (TR) may be identifiable from early episode psychosis and appears to be characterized by negative symptoms and younger age of onset. This mixed method cross-sectional snapshot analysis of antipsychotic (AP) prescribing in an EIPS, explored clozapine eligibility (CE) and prioritization of AP prescribing based on choice, selectivity and appropriateness.

METHOD

We screened 150 service users and 79% (n = 119) were retained after inclusion criteria were applied. We explored CE in all service users who were indicated clozapine based on the product licence (n = 78), and whether there was association between CE and number of hospital admissions, AP trials, age at first episode and duration of untreated psychosis.

RESULTS

Following multidisciplinary clinical discussions, we found that 23 service users were CE; 8 were offered and declined clozapine. When compared to non-CE service users, significant factors associated with CE were history of two or more hospital admissions (Mann-Whitney U = 269, P = .008), more than two trials of two different APs (Mann-Whitney U = 517, P ≤ .01), and younger age first episode (independent-samples t-test, P = .047). A total of 47.5% of all service users had been started on olanzapine as their first AP, despite high risk of cardiometabolic syndrome.

CONCLUSION

We propose that EIP services adopt a proactive approach in screening for TR, taking into account negative symptoms and young age at onset, prioritizing service users with two or more hospital admissions and AP trials.

Prevalence of treatment resistance and clozapine use in early intervention services

BACKGROUND

Treatment resistance causes significant burden in psychosis. Clozapine is the only evidence-based pharmacologic intervention available for people with treatment-resistant schizophrenia; current guidelines recommend commencement after two unsuccessful trials of standard antipsychotics.

AIMS

This paper aims to explore the prevalence of treatment resistance and pathways to commencement of clozapine in UK early intervention in psychosis (EIP) services.

METHOD

Data were taken from the National Evaluation of the Development and Impact of Early Intervention Services study (N = 1027) and included demographics, medication history and psychosis symptoms measured by the Positive and Negative Syndrome Scale (PANSS) at baseline, 6 months and 12 months. Prescribing patterns and pathways to clozapine were examined. We adopted a strict criterion for treatment resistance, defined as persistent elevated positive symptoms (a PANSS positive score ≥16, equating to at least two items of at least moderate severity), across three time points.

RESULTS

A total of 143 (18.1%) participants met the definition of treatment resistance of having continuous positive symptoms over 12 months, despite treatment in EIP services. Sixty-one (7.7%) participants were treatment resistant and eligible for clozapine, having had two trials of standard antipsychotics; however, only 25 (2.4%) were prescribed clozapine over the 12-month study period. Treatment-resistant participants were more likely to be prescribed additional antipsychotic medication and polypharmacy, instead of clozapine.

CONCLUSIONS

Prevalent treatment resistance was observed in UK EIP services, but prescription of polypharmacy was much more common than clozapine. Significant delays in the commencement of clozapine may reflect a missed opportunity to promote recovery in this critical period.

Real-world effectiveness of admissions to a tertiary treatment-resistant psychosis service: 2-year mirror-image study

BACKGROUND

Treatment-resistant schizophrenia is a major disabling illness which often proves challenging to manage in a secondary care setting. The National Psychosis Unit (NPU) is a specialised tertiary in-patient facility that provides evidence-based, personalised, multidisciplinary interventions for complex treatment-resistant psychosis, in order to reduce the risk of readmission and long-term care costs.

AIMS

This study aimed to assess the long-term effectiveness of treatment at the NPU by considering naturalistic outcome measures.

METHOD

Using a mirror image design, we compared the numbers of psychiatric and general hospital admissions, in-patient days, acuity of placement, number of psychotropic medications and dose of antipsychotic medication prescribed before and following NPU admission. Data were obtained from the Clinical Records Interactive Search system, an anonymised database sourced from the South London and Maudsley NHS Trust electronic records, and by means of anonymous linkage to the Hospital Episode Statistics system.

RESULTS

Compared with the 2 years before NPU admission, patients had fewer mental health admissions (1.65 ± 1.44 v. 0.87 ± 0.99, z = 5.594, P < 0.0001) and less mental health bed usage (335.31 ± 272.67 v. 199.42 ± 261.96, z = 5.195 P < 0.0001) after NPU admission. Total in-patient days in physical health hospitals and total number of in-patient days were also significantly reduced (16.51 ± 85.77 v. 2.83 ± 17.38, z = 2.046, P = 0.0408; 351.82 ± 269.09 v. 202.25 ± 261.05, z = 5.621, P < 0.0001). The reduction in level of support required after treatment at the NPU was statistically significant (z = -8.099, P < 0.0001).

CONCLUSIONS

This study demonstrates the long-term effectiveness of a tertiary service specialising in treatment-resistant psychosis.

Evidence-based guidelines for the pharmacological treatment of schizophrenia: Updated recommendations from the British Association for Psychopharmacology

These updated guidelines from the British Association for Psychopharmacology replace the original version published in 2011. They address the scope and targets of pharmacological treatment for schizophrenia. A consensus meeting was held in 2017, involving experts in schizophrenia and its treatment. They were asked to review key areas and consider the strength of the evidence on the risk-benefit balance of pharmacological interventions and the clinical implications, with an emphasis on meta-analyses, systematic reviews and randomised controlled trials where available, plus updates on current clinical practice. The guidelines cover the pharmacological management and treatment of schizophrenia across the various stages of the illness, including first-episode, relapse prevention, and illness that has proved refractory to standard treatment. It is hoped that the practice recommendations presented will support clinical decision making for practitioners, serve as a source of information for patients and carers, and inform quality improvement.

Proinflammatory and anti-inflammatory biomarkers in schizophrenia and influence of simvastatin on the interleukin-6

The present study sought to assess biomarkers of inflammation in stable patients with schizophrenia (SZ) on clozapine therapy. We recruited 60 outpatients with SZ and 60 healthy controls, matched for sex and age. Compared with controls, patients had significantly increased concentrations of interleukin-6 and tumor necrosis factor-α. Interestingly, patients on simvastatin had lower interleukin-6 levels compared with patients not on simvastatin and controls. This study corroborated previous evidence for increased inflammatory biomarkers in SZ and detected a potential anti-inflammatory action of simvastatin in patients with a clinical diagnosis of SZ on clozapine therapy.

Clozapine and all-cause mortality in treatment-resistant schizophrenia: a historical cohort study

OBJECTIVE

Large-scale epidemiological studies have demonstrated a protective effect of clozapine on mortality in people with schizophrenia. Clozapine is reserved for use in patients with treatment-resistant schizophrenia (TRS), but evidence of clozapine's effect on mortality exclusively within TRS samples is inconclusive. Hence, we aimed to investigate the effect of clozapine use on all-cause mortality in TRS patients.

METHODS

A historical patient cohort sample of 2837 patients, who met criteria for TRS between 1 Jan 2008 and 1 Jan 2016, were selected from the South London and Maudsley NHS Foundation Trust (SLAM) electronic health records (EHR). The national Zaponex Treatment Access System (ZTAS) mandatory monitoring system linked to the SLAM EHR was used to distinguish which patients were initiated on clozapine (n = 1025). Cox proportional hazard models were used, adjusting for sociodemographics, clinical monitoring, mental and physical illness severity and functional status.

RESULTS

After controlling for potential confounders, the protective effect of clozapine on all-cause mortality was significant (adjusted hazard ratio 0.61; 95% confidence interval 0.38-0.97; P = 0.04).

CONCLUSIONS

Clozapine reduces the risk of mortality in patients who meet criteria for TRS. We provide further evidence that improving access to clozapine in TRS is likely to reduce the mortality gap in schizophrenia.

Predicting parkinsonism side-effects of antipsychotic polypharmacy prescribed in secondary mental healthcare

BACKGROUND

Computer-modelling approaches have the potential to predict the interactions between different antipsychotics and provide guidance for polypharmacy.

AIMS

To evaluate the accuracy of the quantitative systems pharmacology platform to predict parkinsonism side-effects in patients prescribed antipsychotic polypharmacy.

METHODS

Using anonymized data from South London and Maudsley NHS Foundation Trust electronic health records we applied quantitative systems pharmacology, a neurophysiology-based computer model of humanized neuronal circuits, to predict the risk for parkinsonism symptoms in patients with schizophrenia prescribed two concomitant antipsychotics. The performance of the quantitative systems pharmacology model was compared with the performance of simple parameters such as: combination of affinity constants (1/K_sum); sum of D₂R occupancies (D₂R) and chlorpromazine equivalent dose.

RESULTS

We identified 832 patients with schizophrenia who were receiving two antipsychotics for six or more months, between 1 January 2007 and 31 December 2014. The area under the receiver operating characteristic (AUROC) curve for the quantitative systems pharmacology model was 0.66 ( p = 0.01), while AUROCs for D₂R, 1/K_sum and chlorpromazine equivalent dose were 0.52 ( p = 0.350), 0.53 ( p = 0.347) and 0.52 ( p = 0.330) respectively.

CONCLUSION

Our results indicate that quantitative systems pharmacology has the potential to predict the risk of parkinsonism associated with antipsychotic polypharmacy from minimal source information, and thus might have potential decision-support applicability in clinical settings.

[Psychiatric pharmacotherapy of older individuals with severe mental illness]

BACKGROUND

Chronic schizophrenia, depression, and bipolar disorders, among other chronic psychiatric disorders with onset at youth or early adulthood are often referred to as severe mental illness (SMI). Aging with SMI is associated with various psychosocial, physiological, and medical problems with potential impact on psychiatric pharmacotherapy.

OBJECTIVES

Determination and discussion of problems and special features of the psychopharmacological treatment of older persons with SMI and presentation of treatment recommendations for the distinct diagnoses.

MATERIALS AND METHODS

International literature and guidelines were searched. In addition, the basic literature and expert opinions are discussed.

RESULTS

General problems that influence the psychiatric pharmacotherapy of older persons with SMI include nonadherence, nonresponse, polypharmacy, and distinct pharmacokinetic changes with aging and somatic comorbidity. Psychotropic drugs may exhibit cardiovascular, metabolic, and neuropsychiatric risks, among others. The literature regarding effectiveness of psychotropic drugs, drug groups, or combination of drugs in older patients with SMI is scarce to nonexistent.

CONCLUSIONS

Drug treatment of older persons with SMI should be part of an overall treatment plan that also has to include social and psychotherapeutic components that address the specific problems of this population. Most importantly, psychiatric pharmacotherapy should consider these risks and the treatment should be tailored to a patient's individual risk profile. Due to a general lack of evidence in this special population, treatment strategies of standard guidelines should be adjusted with special consideration to physiological changes of age.

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

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

Long-term antipsychotic polypharmacy prescribing in secondary mental health care and the risk of mortality

OBJECTIVES

To investigate the association between long-term antipsychotic polypharmacy use and mortality; and determine whether this risk varies by cause of death and antipsychotic dose.

METHODS

Using data from a large anonymised mental healthcare database, we identified all adult patients with serious mental illness (SMI) who had been prescribed a single antipsychotic or polypharmacy, for six or more months between 2007 and 2014. Multivariable Cox regression models were constructed, adjusting for sociodemographic, socioeconomic, clinical factors and smoking, to examine the association between APP use and the risk of death.

RESULTS

We identified 10 945 adults with SMI who had been prescribed long-term antipsychotic monotherapy (76.9%) or APP (23.1%). Patients on long-term APP had a small elevated risk of mortality, which was significant in some but not all models. The adjusted hazard ratios for death from natural and unnatural causes associated with APP were 1.2 (0.9-1.4, P = 0.111) and 1.1 (0.7-1.9, P = 0.619) respectively. The strengths of the associations between APP and mortality outcomes were similar after further adjusting for % BNF antipsychotic dose (P = 0.031) or olanzapine equivalence (P = 0.088).

CONCLUSION

The findings suggest that the effect of long-term APP on mortality is not clear-cut, with limited evidence to indicate an association, even after controlling for the effect of dose.