Factors associated with changes in hospitalisation in patients prescribed clozapine

Antipsychotic prescribing practices for outpatients with schizophrenia and reasons for non-clozapine treatment - Data from a Danish quality assessment audit

BACKGROUND

Clozapine is the gold standard for treating treatment-resistant schizophrenia (TRS) although widely underutilised. Both organisational, patient- and clinician related reasons for the underutilisation have been reported, however, the clinical impact of either in real-world settings is not fully elucidated.

AIM

This audit aimed to evaluate the local antipsychotic (AP) prescribing practices for outpatients with schizophrenia and to assess the spectrum and prevalence of journalised reasons for non-clozapine treatment amongst eligible outpatients.

METHODS

Data on demographics, current and former AP treatments, as well as documented reasons for non-clozapine treatment, was extracted through chart audit.

RESULTS

Of the 668 affiliated outpatients with schizophrenia, 43% were treated with AP polytherapy (APP) and 19.6% with clozapine. The most prevalent reason for clozapine discontinuation was related to side effects whereas the most prevalent reason for refusal or omission of clozapine treatment was related to the associated monitoring regimen.

CONCLUSIONS

This audit showed that APP prescribing is a highly prevalent practice in our services when treating outpatients with schizophrenia and that clozapine is underutilised in a 'last resort' manner. The blood-monitoring regimen associated with clozapine treatment was found to be an important factor in the underutilisation. It seemed, however, that the monitoring constituted a barrier for different reasons, requiring different approaches to remedy. Future studies, directly involving both patients and clinicians in the identification and management of the most clinically relevant barriers and their corresponding facilitators, are warranted.

Clinical predictors of response to clozapine in Tunisian patients with treatment resistant schizophrenia

INTRODUCTION

Treatment resistant schizophrenia (TRS), affecting approximately one-third of patients with schizophrenia, is associated with a serious impairment in global psychosocial functioning. Clozapine is the only licensed drug for TRS. However its prescription remains limited by its side effects requiring mandatory monitoring. The need to identify clinical factors associated with good response to clozapine in TRS has been established. The presence of ethnic differences in these factors and the scarcity of data on the Tunisian or more generally the North-African population warrants the conduct of a clinical study on the subject. The aim of this study was to investigate demographic, clinical, and biochemical patient characteristics as potential predictors of response to clozapine.

METHODS

This is a cross-sectional and retrospective study, at the "F and A psychiatry departments" of Razi Hospital in Manouba, Tunisia. All patients, with DSM 5 diagnosis of schizophrenia in its resistant form, on clozapine for at least 12 months and who consulted from June 1, 2018 to November 30, 2018 were included. We investigated premorbid functioning by the premorbid adjusment scale, demographic and clinical characteristics, and clozapine plasma level as potential clozapine response predictors. The response to clozapine was defined by a total BPRS score of 35 or less.

RESULTS

Sixty-three patients were included in the study. The mean age at clozapine introduction was 30,84 ±9,25 years. The mean duration of clozapine treatment was 7,22 ± 4,02 years. There were 16 clozapine responders (25%) who had BPRS total scores below or equal to 35 and 47 non-responders (75%). A higher premorbid social functioning in childhood (p = 0,018) and early adolescence (p = 0,024) was associated with better response to clozapine. A delay clozapine initiation shorter than 7 years(p = 0,036), one atypical antipsychotic trial (p = 0,029) and schizophrenia paranoid subtype (p< 0.01) were found to be significantly predictive of good clozapine response. None of the demographic factors or biochemical characteristics were associated with clozapine response.

CONCLUSIONS

Our work is consistent with previous studies suggesting the need for clinicians to be aware of the clinical predictors of a good response to clozapine to overcome their reluctance to prescribe it. It also highlighted the major prognostic role of premorbid adjustment in the clinical response to treatment. However, prospective studies including therapeutic drug monitoring would be very useful to better delineate the sub-group of patients to whom clozapine would benefit the most and to improve prescription modalities.

COVID-19 infection causes a reduction in neutrophil counts in patients taking clozapine

BACKGROUND

Monitoring of white cell counts during clozapine treatment leads to cessation of therapy if levels fall below predetermined values. Reductions in white cell counts, driven by lower levels of lymphocytes, have been observed with coronavirus disease 2019 (COVID-19). Neutropenia during COVID-19 has not been reported. We present data for 56 patients who were taking clozapine and had COVID-19.

METHODS

We included patients who were taking clozapine at the time they tested positive for COVID-19. We compared absolute neutrophil counts, lymphocyte counts and white cell counts between baseline and the first week of infection, and baseline and the second week of infection.

RESULTS

We observed reductions in absolute neutrophil counts (p = 0.005), lymphocyte counts (p = 0.003) and white cell counts (p < 0.001) between baseline and the first 7 days of COVID-19. All cell counts had returned to baseline levels by days 8 to 14. Six patients experienced neutropenia (absolute neutrophil counts < 2.0 × 109/L) and of those, 4 underwent mandatory cessation of clozapine. For 3 patients, clozapine treatment had been established for more than 6 months with no previous neutropenia, neutrophil levels returned to baseline within 2 weeks and no further neutropenia was observed on restarting treatment.

LIMITATIONS

This was a retrospective chart review; larger cohorts are required. Clozapine plasma levels were largely not measured by clinicians.

CONCLUSION

These data strongly suggest that mild neutropenia in the acute phase of COVID-19 in patients who are well established on clozapine is more likely to be a consequence of the virus than of clozapine treatment.

Demographic and clinical variables associated with response to clozapine in schizophrenia: a systematic review and meta-analysis

Clozapine is the only licensed pharmacotherapy for treatment-resistant schizophrenia. However, response to clozapine is variable. Understanding the demographic and clinical features associated with response to clozapine may be useful for patient stratification for clinical trials or for identifying patients for earlier initiation of clozapine. We systematically reviewed the literature to investigate clinical and demographic factors associated with variation in clozapine response in treatment-resistant patients with schizophrenia spectrum disorders. Subsequently, we performed a random-effects meta-analysis to evaluate differences in duration of illness, age at clozapine initiation, age of illness onset, body weight and years of education between clozapine responders and non-responders. Thirty-one articles were eligible for qualitative review and 17 of these were quantitatively reviewed. Shorter duration of illness, later illness onset, younger age at clozapine initiation, fewer hospitalisations and fewer antipsychotic trials prior to clozapine initiation showed a trend to be significantly associated with a better response to clozapine. Meta-analysis of seven studies, totalling 313 subjects, found that clozapine responders had a significantly shorter duration of illness compared to clozapine non-responders [g = 0.31; 95% confidence interval (CI) 0.06-0.56; p = 0.01]. The results imply that a delay in clozapine treatment may result in a poorer response and that a focus on prompt treatment with clozapine is warranted.

Effect of age on the relative efficacy of clozapine in schizophrenia

OBJECTIVE

Early treatment of schizophrenia improves outcomes. Clozapine appears to have unique benefit when other antipsychotic medication has failed. This systematic review and meta-analysis aims to assess clozapine's superiority over alternative antipsychotic medication and examine whether earlier use is associated with additional benefit.

METHOD

Systematic retrieval of blinded, randomized controlled trials comparing clozapine with alternative antipsychotics in adults with schizophrenia. The effect of mean age on relative clozapine response was examined using random effects meta-regression, and multiple linear regression on available patient data.

RESULTS

A total of 276 studies were retrieved. Thirty-four studies were included in the meta-analysis. Clozapine was significantly more effective than alternative antipsychotics in reducing psychotic symptoms and increasing response. However, meta-regression failed to show a more significant effect in younger patients (age on effect size (total psychotic symptoms) 0.00, P = 0.79 CI -0.03 to 0.03). Individual patient data were available for two studies, the larger of which showed a significant interaction between younger age and superiority of clozapine.

CONCLUSION

The results support clozapine's superiority over other antipsychotics. A convincing effect of age on this effect was not demonstrated, although this was suggested in one study. In view of the age of many of the included studies, and changes in reporting practice over time, new clozapine RCTs, which include age of illness onset as well as age at trial time, would be welcome in order to provide meta-analysable data for future use.

[Not Available]

Objective:

The potential of clozapine in severe bipolar disorder is suggested by its efficacy in refractory schizophrenia, but the evidence is limited thus far. This report utilizes data from the standard care pathway of the Systematic Treatment Enhancement Program to examine the clinical impact of clozapine in bipolar disorder, comparing it to two groups, one that received olanzapine and an additional group that received neither drug.

Method:

A total of 4,032 outpatients were available for this analysis. Groups for longitudinal analyses are based on the medication used at each visit. Outcomes assessed were clinical status, symptoms subscales, hospitalizations, and death. We utilized mixed models and generalized estimating equations to adjust for baseline differences and investigate longitudinal differences in symptoms, clinical status, and hospitalization rates between groups.

Results:

During the study, 1.1% (n = 43) of the patients used clozapine at any time. Those on clozapine had significantly fewer manic and depressive symptoms during follow-up as compared with those on neither clozapine nor olanzapine, while those on olanzapine had more symptoms. The use of clozapine was not associated with an increased risk of hospitalization. No deaths were recorded for clozapine group during the trial.

Conclusions:

Although prescribed to very few patients, the impact of clozapine was notable, with fewer symptoms in patients who had more severe illnesses at baseline. Clozapine could prove to be as successful an intervention for late-stage bipolar disorder as it has been in schizophrenia.

The impact of clozapine initiation and cessation on psychiatric hospital admissions and bed days: a mirror image cohort study

BACKGROUND

Clozapine is the most effective medication for the positive symptoms of treatment-refractory schizophrenia. Although clozapine use is associated with fewer admissions, less is known about the impact of clozapine cessation on hospitalisation.

AIMS

The aims of this study were to investigate whether clozapine-reduced psychiatric inpatient admissions and bed days, and investigate patient factors associated with these changes from a sample of 1906 people commenced on clozapine.

METHODS

All people commencing clozapine during an acute hospitalisation over a 10-year period in Queensland, Australia, were included in this retrospective cohort study. A mirror image design was used to compare psychiatric bed days and hospitalisations 2 years before and after clozapine treatment, and the impact of clozapine continuation or early cessation. Changes in psychiatric bed days and hospitalisations were analysed using linear regression, adjusting for the duration on clozapine, sex, age, indigenous status, country of origin and time to clozapine commencement.

RESULTS/OUTCOMES

There was a significant reduction in bed days (29.55 days vs 24.46 days, p < 0.001) and admissions (2.27 vs 1.87 < 0.001) associated with clozapine commencement. This remained significant among clozapine continuers, but not among those with early cessation. Longer duration on clozapine was associated with greater reductions in psychiatric bed days and admissions. Age, sex and time to clozapine commencement, indigeneity and country of origin did not impact outcomes.

CONCLUSION/INTERPRETATION

Longer clozapine therapy led to a greater reduction in psychiatric bed days and hospitalisations. Early cessation was associated with a return to pre-clozapine levels of bed days and admissions.

Risk of readmission in patients with schizophrenia and schizoaffective disorder newly prescribed clozapine

BACKGROUND

Insight into the effect of clozapine is limited by a lack of controlling for confounding variables in current research. Our objective was to investigate the association between clozapine prescribed at discharge, following an inpatient episode, and risk of readmission into secondary mental health services in patients with schizophrenia and schizoaffective disorder, controlling extensively for confounding variables.

METHODS

Clinical records from 3651 patients were analysed in a retrospective observational cohort study. Cox proportional-hazards regression models were used to assess the risk of hospital readmission. A series of sensitivity analyses were also conducted. Propensity score methods were used to address confounding-by-indication.

RESULTS

Patients on clozapine ( n=202) had a reduced risk of readmission compared with patients on other antipsychotics (adjusted hazard ratio=0.79; 95% confidence interval: 0.64-0.99; p=0.043). Clozapine also had a protective effect on risk of readmission when compared with olanzapine (adjusted hazard ratio 0.76; 95% confidence interval: 0.60-0.96; p=0.021). The effect size remained consistent after adjusting for an array of possible confounders, as well as using propensity scores to address confounding-by-indication. A statistically significant result was also noted in all but two sensitivity analyses.

CONCLUSION

Our findings suggest that clozapine is associated with a reduced risk of readmission into secondary mental health services.

Long-term follow-up of clozapine prescribing

OBJECTIVE

Clozapine is uniquely effective for treatment-resistant schizophrenia, and so treatment continuation is essential. We aimed to identify factors associated with an increased likelihood of clozapine discontinuation in a cohort of patients in South East London.

METHODS

We gathered demographic and treatment information such as duration of illness and antipsychotic treatment history. t-tests, chi-square tests and binary logistic regression were used to compare patients who continued and discontinued clozapine during the study and to identify predictor variables for discontinuation.

RESULTS

Out of the study population of 133 patients, 48 discontinued clozapine at least once during the study period. The majority of these (75%) stopped treatment within the first 4 years of clozapine therapy. Age, ethnicity, diagnosis and antipsychotic treatment history were not predictive of the risk of clozapine discontinuation. However, male patients were more likely to stop taking clozapine (χ² = 6.81, p = 0.009). The odds of discontinuing clozapine were 2.15 times higher for male patients. The most common reason for discontinuation was patient refusal of treatment.

CONCLUSION

We found that patients who discontinue clozapine are more likely to be male, but no other demographic variable was found to predict treatment cessation. Discontinuation usually occurred due to patient refusal of treatment.

Antipsychotic polypharmacy prescribing and risk of hospital readmission

OBJECTIVES

The aim of this study was to determine if there was an association between being discharged on antipsychotic polypharmacy (APP) and risk of readmission into secondary mental health care.

METHODS

Using data from the South London and Maudsley (SLAM) case register, service users with serious mental illness (SMI), discharged between 1st January 2007 and 31th December 2014, were followed up for 6 months. Patients were classified as receiving either monotherapy or polypharmacy at index discharge. Multivariable Cox regression models were constructed, adjusting for sociodemographic, socioeconomic, clinical and service use factors.

RESULTS

We identified 5523 adults who had been admitted at least once to SLAM, of whom 1355 (24.5%) were readmitted into secondary mental health care. In total, 15% (n = 826) of patients were discharged on APP and 85% (n = 4697) on monotherapy. Of these, 30.9% (n = 255) and 23.4% (n = 1100) were readmitted respectively. Being discharged on APP was associated with a significantly increased risk of readmission, in comparison to patients discharged on monotherapy (HR = 1.4, 1.2-1.7, p < 0.001). This association was maintained in the fully adjusted model and following several sensitivity analyses. We further established that patients receiving clozapine APP (n = 200) were at a significantly increased risk for readmission in comparison to patients on clozapine monotherapy (HR = 1.8, 1.2-2.6, p = 0.008).

CONCLUSIONS

Our results suggest that patients discharged on APP are more likely to be readmitted into hospital within 6 months in comparison to those discharged on monotherapy. This needs to be considered in treatment decisions and the reasons for the association clarified.