The cost-effectiveness of clozapine: a controlled, population-based, mirror-image study

Decoding Clozapine-Induced Agranulocytosis: Unraveling Interactions and Mitigation Strategies

Agranulocytosis represents a severe complication associated with the administration of clozapine. Clozapine is an antipsychotic medication that has demonstrated substantial efficacy in remediating refractory schizophrenia and various other psychiatric disorders. Nonetheless, it is crucial to monitor patients for neutropenia regularly during clozapine therapy. Therefore, this article aimed to delve into the prevalence of agranulocytosis during clozapine treatment by scrutinizing the extant literature to discern trends and correlations. This review endeavored to explore factors such as drug interactions, dose-related factors, duration of treatment, and genetic predispositions that could potentially influence the likelihood of patients developing agranulocytosis while undergoing clozapine therapy. Moreover, this review enunciates the ramifications of agranulocytosis on both patients and healthcare providers and meticulously evaluates the strategies to mitigate this risk and ensure optimal patient outcomes.

Variation of Clozapine Use for Treatment of Schizophrenia: Evidence from Pennsylvania Medicaid and Dually Eligible Enrollees

While clozapine is the most effective antipsychotic treatment for treatment-resistant schizophrenia, it remains underutilized across the United States, warranting a more comprehensive understanding of variation in use at the county level, as well as characterization of existing prescribing patterns. Here, we examined both Medicaid and Medicare databases to (1) characterize temporal and geographic variation in clozapine prescribing and, (2) identify patient-level characteristics associated with clozapine use. We included Medicaid and Fee for Service Medicare data in the state of Pennsylvania from January 1, 2013, through December 31, 2019. We focused on individuals with continuous enrollment, schizophrenia diagnosis, and multiple antipsychotic trials. Geographic variation was examined across counties of Pennsylvania. Regression models were constructed to determine demographic and clinical characteristics associated with clozapine use. Out of 8,255 individuals who may benefit from clozapine, 642 received treatment. We observed high medication burden, overall, including multiple antipsychotic trials. We also identified variation in clozapine use across regions in Pennsylvania with a disproportionate number of prescribers in urban areas and several counties with no identified clozapine prescribers. Finally, demographic, and clinical determinants of clozapine use were observed including less use in people identified as non-Hispanic Black, Hispanic, or with a substance use disorder. In addition, greater medical comorbidity was associated with increased clozapine use. Our work leveraged both Medicaid and Medicare data to characterize and surveil clozapine prescribing. Our findings support efforts monitor disparities and opportunities for the optimization of clozapine within municipalities to enhance clinical outcomes.

Real-world clinical and cost-effectiveness of community clozapine initiation: mirror cohort study

BACKGROUND

Clozapine is the only drug licensed for treatment-resistant schizophrenia (TRS) but the real-world clinical and cost-effectiveness of community initiation of clozapine is unclear.

AIMS

The aim was to assess the feasibility and cost-effectiveness of community initiation of clozapine.

METHOD

This was a naturalistic study of community patients recommended for clozapine treatment.

RESULTS

Of 158 patients recommended for clozapine treatment, 88 (56%) patients agreed to clozapine initiation and, of these, 58 (66%) were successfully established on clozapine. The success rate for community initiation was 65.4%; which was not significantly different from that for in-patient initiation (58.82%, χ²(1,88) = 0.47, P = 0.49). Following clozapine initiation, there was a significant reduction in median out-patient visits over 1 year (from 24.00 (interquartile range (IQR) = 14.00-41.00) to 13.00 visits (IQR = 5.00-24.00), P < 0.001), and 2 years (from 47.50 visits (IQR = 24.75-71.00) to 22.00 (IQR = 11.00-42.00), P < 0.001), and a 74.71% decrease in psychiatric hospital bed days (z = -2.50, P = 0.01). Service-use costs decreased (1 year: -£963/patient (P < 0.001); 2 years: -£1598.10/patient (P < 0.001). Subanalyses for community-only initiation also showed significant cost reductions (1 year: -£827.40/patient (P < 0.001); 2 year: -£1668.50/patient (P < 0.001) relative to costs prior to starting clozapine. Relative to before initiation, symptom severity was improved in patients taking clozapine at discharge (median Positive and Negative Syndrome Scale total score: initial visit: 80 (IQR = 71.00-104.00); discharge visit 50.5 (IQR = 44.75-75.00), P < 0.001) and at 2 year follow-up (Health of Nation Outcome Scales total score median initial visit: 13.00 (IQR = 9.00-15.00); 2 year follow-up: 8.00 (IQR = 3.00-13.00), P = 0.023).

CONCLUSIONS

These findings indicate that community initiation of clozapine is feasible and is associated with significant reductions in costs, service use and symptom severity.

A potential biomarker for treatment stratification in psychosis: evaluation of an [18F] FDOPA PET imaging approach

[¹⁸F]FDOPA PET imaging has shown dopaminergic function indexed as K_i^cer differs between antipsychotic treatment responders and non-responders. However, the theragnostic potential of this biomarker to identify non-responders has yet to be evaluated. In view of this, we aimed to evaluate this as a theragnostic test using linear and non-linear machine-learning (i.e., Bernoulli, support vector, random forest and Gaussian processes) analyses and to develop and evaluate a simplified approach, standardised uptake value ratio (SUVRc). Both [¹⁸F]FDOPA PET approaches had good test-rest reproducibility across striatal regions (K_i^cer ICC: 0.68-0.94, SUVRc ICC: 0.76-0.91). Both our linear and non-linear classification models showed good predictive power to distinguish responders from non-responders (receiver operating curve area under the curve for region-of-interest approach: K_i^cer = 0.80, SUVRc = 0.79; for voxel-wise approach using a linear support vector machine: 0.88) and similar sensitivity for identifying treatment non-responders with 100% specificity (K_i^cer: ~50%, SUVRc: 40-60%). Although the findings were replicated in two independent datasets, given the total sample size (n = 84) and single setting, they warrant testing in other samples and settings. Preliminary economic analysis of [¹⁸F]FDOPA PET to fast-track treatment-resistant patients with schizophrenia to clozapine indicated a potential healthcare cost saving of ~£3400 (equivalent to $4232 USD) per patient. These findings indicate [¹⁸F]FDOPA PET dopamine imaging has potential as biomarker to guide treatment choice.

A retrospective study of intramuscular clozapine prescription for treatment initiation and maintenance in treatment-resistant psychosis

BACKGROUND

Clozapine is uniquely effective in treatment-resistant psychosis but remains underutilised, partly owing to psychotic symptoms leading to non-adherence to oral medication. An intramuscular formulation is available in the UK but outcomes remain unexplored.

AIMS

This was a retrospective clinical effectiveness study of intramuscular clozapine prescription for treatment initiation and maintenance in treatment-resistant psychosis over a 3-year period.

METHOD

Successful initiation of oral clozapine after intramuscular prescription was the primary outcome. Secondary outcomes included all-cause clozapine discontinuation 2 years following initiation, and 1 year after discharge. Discontinuation rates were compared with a cohort prescribed only oral clozapine. Propensity scores were used to address confounding by indication.

RESULTS

Among 39 patients prescribed intramuscular clozapine, 19 received at least one injection, whereas 20 accepted oral clozapine when given an enforced choice between the two. Thirty-six (92%) patients successfully initiated oral clozapine after intramuscular prescription; three never transitioned to oral. Eight discontinued oral clozapine during the 2-year follow-up, compared with 83 out of 162 in the comparator group (discontinuation rates of 24% and 50%, respectively). Discontinuation rates at 1-year post-discharge were 21%, compared with 44% in the comparison group. Intramuscular clozapine prescription was associated with a non-significantly lower hazard of discontinuation 2 years after initiation (hazard ratio 0.39, 95% CI 0.14-1.06) and 1 year after discharge (hazard ratio 0.37, 95% CI 0.11-1.24). The only reported adverse event specific to the intramuscular formulation was injection site pain and swelling.

CONCLUSIONS

Intramuscular clozapine prescription allowed transition to oral maintenance in an initially non-adherent cohort. Discontinuation rates were similar to patients only prescribed oral clozapine and comparable to existing literature.

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.

Continuation of clozapine treatment: practice makes perfect

Aims and Method

The study aimed to identify the predictors of drop-out from clozapine treatment by examining the demographic and clinical characteristics of patients registered on clozapine within a 6-month period in one NHS Trust.

Results

During the study period, 54 patients were registered and began clozapine treatment and 31% had discontinued within 6 months. Two people died and the remainder discontinued because of non-compliance or side-effects, including neutropenia. Two factors were predictive: the age of the patient (older patients were more likely to discontinue) and the hospital where the initial registration was made.

Clinical Implications

Neither ethnicity, previous registration nor the individual prescriber are a bar to successful persistence with clozapine. However, one set of hospitals with a history of evidence-based practice and high clozapine prescribing was more successful in retaining patients on maintenance treatment. Although specific data are needed to identify more subtle contributing factors to continuation, it is clear that there is scope for improving the rate of persistence with clozapine treatment.

Continuation of clozapine treatment: practice makes perfect

Aims and Method

The study aimed to identify the predictors of drop-out from clozapine treatment by examining the demographic and clinical characteristics of patients registered on clozapine within a 6-month period in one NHS Trust.

Results

During the study period, 54 patients were registered and began clozapine treatment and 31% had discontinued within 6 months. Two people died and the remainder discontinued because of non-compliance or side-effects, including neutropenia. Two factors were predictive: the age of the patient (older patients were more likely to discontinue) and the hospital where the initial registration was made.

Clinical Implications

Neither ethnicity, previous registration nor the individual prescriber are a bar to successful persistence with clozapine. However, one set of hospitals with a history of evidence-based practice and high clozapine prescribing was more successful in retaining patients on maintenance treatment. Although specific data are needed to identify more subtle contributing factors to continuation, it is clear that there is scope for improving the rate of persistence with clozapine treatment.

Underuse of clozapine in treatment-resistant schizophrenia

Up to a third of patients with schizophrenia develop treatment resistance. Clozapine has been established as the most effective antipsychotic medication for treatment-resistant schizophrenia. However, it is significantly underutilised in this population. Possible reasons include clinicians' lack of experience with the drug and negative attitudes towards it. African-Caribbean patients are less likely to be treated with clozapine compared with their White counterparts and more likely to have treatment discontinued due to perceived risk of agranulocytosis. This paper discusses the current evidence relating to the underuse of clozapine and factors responsible for this.

Bipolar patients treated with long-acting injectable risperidone in Taiwan: A 1-year mirror-image study using a national claims database

OBJECTIVE

Bipolar disorder (BD) is burdensome for patients and healthcare systems. This study evaluated changes in concomitant medication patterns, healthcare utilization, and costs after the initiation of risperidone long-acting injection (RLAI) treatment among BD patients.

METHOD

287 BD patients receiving regular RLAI treatment for 1 year were identified from the Taiwan National Health Insurance Research database during 2007-2012. The bootstrapping procedure was performed to create 1000 samples to generate normally distributed data. The paired t-tests with a correction for multiple comparisons using Bonferroni correction were used to compare the proportion of patients of concomitant psychiatric medication and resource use and costs between pre- and post-RLAI periods. Rapid and non-rapid cycling stratification was performed based on the number of change-in-mood episodes within 1 year prior to the index date.

RESULTS

The mean annual dose of RLAI was 638.41mg, which was equal to an average dose of 24.6mg every 2 weeks. The prevalence of concomitant use of conventional antipsychotics, atypical antipsychotics, lithium, and antidepressants decreased from the pre-RLAI period to the post-RLAI period by 23.75%, 31.91%, 1.29%, and 7.08%, respectively. RLAI use decreased emergency room (ER) visits, hospital admissions, length of hospital stay, and non-medication costs (all P<0.0001). The cost savings with RLAI were attributed to lower hospitalization costs in spite of higher medication costs. Moreover, rapid cycling patients (n=36) demonstrated greater reduction in ER and inpatient services with RLAI than non-rapid cycling patients (n=251).

LIMITATIONS

Of the patients who initiated RLAI, 15% of them who had regular treatment were included. Furthermore, data on measures of symptom severity, side effects, and hyperprolactinemia were not available.

CONCLUSION

BD patients had lower inpatient and ER utilization, and non-medication costs after using RLAI. In addition, RLAI use decreased the number of change-in-mood episodes in rapid cycling patients; which provides additional insights into the treatment of rapid cycling BD patients.

The impact of switching to clozapine on psychiatric hospital admissions: a mirror-image study

Background

Clozapine is an atypical antipsychotic agent used primarily in the management of treatment-resistant schizophrenia. Previous studies have demonstrated clozapine’s superior efficacy over other antipsychotic medications in treating this population of patients. The aim of this study was to assess if the number of hospital admissions and days spent in hospital reduced with the initiation of clozapine, compared with when the same sample of patients were prescribed other antipsychotics prior to clozapine initiation.

Method

A mirror-image study design was adopted. In this case the intervention under study was the initiation of clozapine. Information was collected retrospectively from the charts of patients attending the University Hospital Galway clozapine clinic. The number of admissions and number of hospital days were collected for each patient over the 3 years before and after clozapine initiation. Wilcoxon’s signed-rank test was used to test for statistical significance.

Results

The total sample size comprised of 62 patients, of which the majority were male (74.2%) and had a diagnosis of schizophrenia (82.3%). The mean dose of clozapine was 417 mg, and mean age of the sample was 38 years. Mean number of hospital admissions reduced from 2.8 to 0.8 (p<0.0001) following initiation of clozapine. Mean number of days spent in hospital reduced from 116.4 to 17.1 (p<0.0001).

Conclusion

After initiation of clozapine treatment, patients experience a substantial reduction in number of hospital admissions and number of days spent in hospital when compared with a similar period prior to clozapine initiation.

The impact of clozapine on hospital use: a systematic review and meta-analysis

OBJECTIVE

The objective of this study was to perform a systematic review and meta-analysis of studies reporting the impact of clozapine on hospital use in people with a psychotic illness.

METHOD

PubMed, EMBASE, PsycINFO and the Cochrane Schizophrenia Group Trials Register were systematically searched from inception to 12 October 2016. We included all trials and observational studies, except case reports.

RESULTS

Thirty-seven studies were included. Clozapine significantly reduced the proportion of people hospitalised compared to control medicines (RR = 0.74; 95% CI: 0.69-0.80, P < 0.001, 22 studies, n = 44 718). There were significantly fewer bed days after clozapine treatment compared to before clozapine treatment in both controlled (MD = -34.41 days; 95% CI: -68.22 to -0.60 days, P = 0.046, n = 162) and uncontrolled studies (MD = -52.86 days; 95% CI: -79.86 days to -25.86 days, P < 0.001, n = 2917). Clozapine and control medicines had a similar time to rehospitalisation (-19.90 days; 95% CI: -62.42 to 22.63 days, P = 0.36).

CONCLUSION

Clozapine treatment reduced the number of people hospitalised and the number of bed days after treatment compared with before treatment. Clozapine has the potential to reduce acute hospital use among people with treatment refractory schizophrenia.

Clozapine treatment and discontinuation in Iceland: A national longitudinal study using electronic patient records

BACKGROUND

Clozapine is the only drug approved for treatment-resistant schizophrenia. There is evidence that clozapine is underutilized.

AIMS

To evaluate the initiation and discontinuation of clozapine at Landspitali University Hospital in Iceland and the prevalence of antipsychotic polypharmacy in clozapine-treated patients.

METHODS

The study is a part of an ongoing longitudinal study of schizophrenia in Iceland. We identified 201 patients on clozapine or who have been on clozapine by using a keyword search in the electronic health records and by reviewing their medical records.

RESULTS

Mean age at first treatment with clozapine was 37.8 years. Mean follow-up period on clozapine was 11 years. After 20 years of treatment 71.2% of patients were still on clozapine. After one year of treatment 84.4% of patients were still receiving clozapine treatment. We estimate that 11.4% of patients with schizophrenia in Iceland are taking clozapine and that 16% have been treated with clozapine at some point. Polypharmacy is common, since nearly 2/3, 65.6%, of patients taking clozapine use at least one other antipsychotic and 16.9% are also receiving depot injections.

CONCLUSIONS

We need to increase the awareness of psychiatrists in Iceland with regard to treatment with clozapine, since only about half of the estimated population of patients with treatment-resistant schizophrenia in Iceland have ever been treated with clozapine. Nearly two thirds of patients who are prescribed clozapine in Iceland remain on it long-term.

Association between antipsychotic/antidepressant drug treatments and hospital admissions in schizophrenia assessed using a mental health case register

Background:

The impact of psychotropic drug choice upon admissions for schizophrenia is not well understood.

Aims:

To examine the association between antipsychotic/antidepressant use and time in hospital for patients with schizophrenia.

Methods:

We conducted an observational study, using 8 years’ admission records and electronically generated drug histories from an institution providing secondary mental health care in Cambridgeshire, UK, covering the period 2005–2012 inclusive. Patients with a coded ICD-10 diagnosis of schizophrenia were selected. The primary outcome measure was the time spent as an inpatient in a psychiatric unit. Antipsychotic and antidepressant drugs used by at least 5% of patients overall were examined for associations with admissions. Periods before and after drug commencement were compared for patients having pre-drug admissions, in mirror-image analyses correcting for overall admission rates. Drug use in one 6-month calendar period was used to predict admissions in the next period, across all patients, in a regression analysis accounting for the effects of all other drugs studied and for time.

Results:

In mirror-image analyses, sulpiride, aripiprazole, clozapine, and olanzapine were associated with fewer subsequent admission days. In regression analyses, sulpiride, mirtazapine, venlafaxine, and clozapine–aripiprazole and clozapine–amisulpride combinations were associated with fewer subsequent admission days.

Conclusions:

Use of these drugs was associated with fewer days in hospital. Causation is not implied and these findings require confirmation by randomized controlled trials.

A systematic review of the predictors of health service utilisation by adults with mental disorders in the UK

OBJECTIVES

To identify variables that predict health service utilisation (HSU) by adults with mental disorders in the UK, and to determine the evidence level for these predictors.

DESIGN

A narrative synthesis of peer-reviewed studies published after the year 2000. The search was conducted using four databases (ie, PsycINFO, CINAHL Plus with full text, MEDLINE and EMBASE) and completed on 25 March 2014.

SETTING

The majority of included studies were set in health services across primary, secondary, specialist and inpatient care. Some studies used data from household and postal surveys.

PARTICIPANTS

Included were UK-based studies that predicted HSU by adults with mental disorders. Participants had a range of mental disorders including psychotic disorders, personality disorders, depression, anxiety disorders, eating disorders and dementia.

PRIMARY OUTCOME

A wide range of HSU outcomes were examined, including general practitioner (GP) contacts, medication usage, psychiatrist contacts, psychotherapy attendances, inpatient days, accident and emergency admissions and 'total HSU'.

RESULTS

Taking into account study quality, 28 studies identified a range of variables with good preliminary evidence supporting their ability to predict HSU. Of these variables, comorbidity, personality disorder, age (heterogeneous age ranges), neurotic symptoms, female gender, a marital status of divorced, separated or widowed, non-white ethnicity, high previous HSU and activities of daily living, were associated with increased HSU. Moreover, good preliminary evidence was found for associations of accessing a primary care psychological treatment service and medication use with decreased HSU.

CONCLUSIONS

The findings can inform decisions about which variables might be used to derive mental health clusters in 'payment by results' systems in the UK. The findings also support the need to investigate whether combining broad diagnoses with care pathways is an effective method for mental health clustering, and the need for research to further examine the association between mental health clusters and HSU.

The practical management of refractory schizophrenia--the Maudsley Treatment REview and Assessment Team service approach

OBJECTIVE

To describe a practical approach to the community management of treatment-resistant schizophrenia (TRS).

METHOD

A descriptive review of an approach to the assessment and management of patients with TRS, including the community titration of clozapine treatment, and a report of the management recommendations for the first one hundred patients assessed by the Treatment REview and Assessment Team (TREAT).

RESULTS

The standardized model for the community assessment, management and titration of clozapine is described. To date, 137 patients have been referred to this service and 100 patients (72%) attended for assessment. Of these, 33 have been initiated on clozapine while fifteen have had clozapine recommended but have not wished to undertake clozapine treatment. Other management options recommended have included augmentation strategies and long-acting injectable antipsychotics.

CONCLUSION

The service had increased the number of patients receiving community assessment and initiation of clozapine by five-fold relative to the rate prior to the establishment of the service. The large number of referrals and high attendance rate indicates that there is clinical demand for the model. Systematic evaluation is required to determine the clinical and cost-effectiveness of this model and its potential application to other clinical settings.

Systematic review of long-acting injectables versus oral atypical antipsychotics on hospitalization in schizophrenia

OBJECTIVE

To assess the impact of long-acting injectables (LAIs) versus oral antipsychotics (OAs) on hospitalizations among patients with schizophrenia by conducting a systematic literature review of studies with different study designs and performing a meta-analysis.

METHODS

Using the PubMed database and major psychiatric conference proceedings, a systematic literature review for January 2000 to July 2013 was performed to identify English-language studies evaluating schizophrenia patients treated with atypical antipsychotics. Studies reporting hospitalization rates as a percentage of patients hospitalized or as the number of hospitalizations per person per year were selected. The primary meta-analysis assessed the percentage decrease in hospitalization rates before and after treatment initiation for matched time periods. The secondary meta-analysis assessed the absolute rate of hospitalization during follow-up. Pooled treatment-effect estimates were calculated using random-effects models. To account for differences in patient and study-level characteristics between studies, meta-regression analyses were used. Subset analyses further explored the heterogeneity across study designs.

RESULTS

Fifty-eight studies evaluating 25 arms (LAIs: 13 arms, 4516 patients; OAs: 12 arms, 23,516 patients) in the primary meta-analysis and 78 arms (LAIs: 12 arms, 4481 patients; OAs: 66 arms, 96,230 patients) in the secondary meta-analysis were identified. Reduction in hospitalization rates for LAIs was 20.7 percentage points higher than that of OAs (random-effects estimates: LAIs = 56.2% vs. OAs = 35.5%, P = 0.023). Controlling for patient and study characteristics, the adjusted percentage reduction in hospitalization rates for LAIs was 26.4 percentage points higher than for OAs (95% CI: 3.3-49.5, P = 0.027). As for the secondary meta-analysis, no significant difference between LAIs and OAs was observed (random-effects estimate: -8.6, 95% CI: -18.1-1.0, P = 0.077). Subset analyses across type of study yielded consistent results. Limitations of this analysis include the long observation period, which may not reflect current treatment patterns, the use of all-cause hospitalization, which may not be solely related to schizophrenia, and the fact that most studies in the LAI cohort evaluated risperidone.

CONCLUSION

The primary results of this meta-analysis, including studies with both interventional and non-interventional designs and using meta-regressions, suggest that LAIs are associated with higher reductions in hospitalization rates for schizophrenia patients compared to OAs.

Practitioner attitudes to clozapine initiation

OBJECTIVE

Clozapine is the most effective antipsychotic for treatment-resistant schizophrenia. It is recommended as third-line treatment for schizophrenia in national and local guidelines. Despite this, it is underutilised. This survey aimed to clarify barriers to prescribing and elucidate factors that may improve patient access to clozapine.

METHOD

A questionnaire was made available to all staff members at South London and Maudsley NHS Foundation Trust.

RESULTS

In total, 144 clinical staff completed the questionnaire. The majority (81%) of respondents were 'fairly' or 'very' familiar with clozapine prescribing guidelines. Barriers to prescribing most commonly stated as being 'very frequently' a problem were patient concerns about tolerability of clozapine or patient refusal to adhere to blood test monitoring. Staff members also felt medical complications frequently prevented clozapine prescription. Dedicated staff or day hospital placements devoted to clozapine initiation were identified as factors most likely to increase prescribing of clozapine.

CONCLUSION

Professionals identified the dominant barriers to prescribing as being patient focussed - refusal of blood test monitoring or concerns about tolerability. Clinician fears about compliance or medical complications were also important. The development of out-patient services specifically tasked with initiating clozapine may help to increase the frequency of prescribing of clozapine earlier in treatment than is currently seen.

Definitions and drivers of relapse in patients with schizophrenia: a systematic literature review

Relapse in patients with schizophrenia has devastating repercussions, including worsening symptoms, impaired functioning, cognitive deterioration and reduced quality of life. This progressive decline exacerbates the burden of illness on patients and their families. Relapse prevention is identified as a key therapeutic aim; however, the absence of widely accepted relapse definition criteria considerably hampers achieving this goal. We conducted a literature review in order to investigate the reporting of relapses and the validity of hospitalization as a proxy for relapse in patients with schizophrenia. The primary aim was to assess the range and validity of methods used to define relapse in observational or naturalistic settings. The secondary aim was to capture information on factors that predicted or influenced the risk of relapse. A structured search of the PubMed database identified articles that discussed relapse, and hospitalization as a proxy of relapse, in patients with schizophrenia. National and international guidelines were also reviewed. Of the 150 publications and guidelines identified, 87 defined relapse and 62% of these discussed hospitalization. Where hospitalization was discussed, this was as a proxy for, or a component of, relapse in the majority of cases. However, hospitalization duration and type varied and were not always well defined. Scales were used to define relapse in 53 instances; 10 different scales were used and multiple scales often appeared within the same definition. There were 95 references to factors that may drive relapse, including non-adherence to antipsychotic medication (21/95), stress/depression (11/95) and substance abuse (9/95). Twenty-five publications discussed the potential of antipsychotic therapy to reduce relapse rates-continuous antipsychotic therapy was associated with reduced frequency and duration of hospitalization. Non-pharmacological interventions, such as psychoeducation and cognitive behavioural therapy, were also commonly reported as factors that may reduce relapse. In conclusion, this review identified numerous factors used to define relapse. Hospitalization was the factor most frequently used and represents a useful proxy for relapse when reporting in a naturalistic setting. Several factors were reported to increase the risk of relapse, and observation of these may aid the identification of at-risk patients.

Geographical and temporal variations in clozapine prescription for schizophrenia

Despite its unsurpassed efficacy in treatment-resistant schizophrenia, clozapine remains underutilized. Trends in the prescription of clozapine in patients with ICD-10 F20.x schizophrenia were assessed using data from Danish national registers. Three substudies were carried out: (i) an assessment of differences in national prescription patterns between 1996 and 2007 using a cross-sectional design; (ii) a comparison of time from first schizophrenia diagnosis to first prescription of clozapine in a five-year cohort study, using the Cox regression model, of two patient groups who were first diagnosed in 1996 and in 2003; (iii) an assessment of differences in the general psychiatric hospitals' use of clozapine in 2009. The results are as follows: (i) The percentage of schizophrenia patients receiving clozapine rose from 9.0% in 1996 to 10.1% in 2007 (p<0.001). In the same period, the percentage of patients having clozapine treatment augmented with another antipsychotic increased from 43.1% to 64.2%, p<0.001. (ii) Time from diagnosis with schizophrenia until first clozapine prescription was longer for patients diagnosed in 2003 compared to those diagnosed in 1996 (HR: 0.28 CI: 0.16-0.49). (iii) In 2009 there was significant variation in clozapine administration from one hospital to the other, with percentages of patients receiving the drug ranging from 5.7% to 16.8%, with 10.2% as the national mean. Although, the percentage of schizophrenia patients receiving clozapine increased from 1996 to 2007, the time from diagnosis of schizophrenia until first prescription of clozapine increased.

Predictors of clozapine response in patients with treatment-refractory schizophrenia: results from a Danish Register Study

We aimed to identify factors associated with greater clozapine response to guide targeted clozapine use. The study was based on data from the Danish Psychiatric Central Research Register and the National Prescription Database including schizophrenia patients initiating clozapine from 1997 to 2006. Cox regression was used to identify predictors of time to psychiatric hospitalization and all-cause discontinuation from first clozapine prescription. In a 2-year mirror-image design, multiple logistic regression models were used to identify predictors of psychiatric hospitalization. Among 633 schizophrenia patients starting clozapine, shorter time to admission was predicted by increasing number of different antipsychotics (hazard ratio [HR], 1.08/trial; confidence interval [CI], 1.01-1.15/trial) and admissions (HR, 1.04/admission; CI, 1.03-1.05/admission) before first clozapine prescription, earlier onset of schizophrenia (HR, 0.98/y; CI, 0.96-0.99/y), and lower clozapine dose (HR, 0.07/100 mg; CI, 0.03-0.13/100 mg). In the 2-year mirror-image model, during clozapine treatment, there was a significant reduction in bed-days (269.9 days [CI, 238.3-287.8 days] to 64.2 days [CI, 53.0-79.3 days], P < 0.001) and admissions (3.4 [CI, 3.1-3.6] to 2.2 [CI, 1.9-2.5], P < 0.011). Being admitted during clozapine treatment was also associated with more antipsychotic trials (odds ratio [OR], 1.11; CI, 1.00-1.22) and admissions before clozapine initiation (OR, 1.08; CI, 1.04-1.11) and female sex (OR, 1.84; CI, 1.31-2.58). Although the study design does not allow any causal inferences, all 3 models suggested a lower number of psychiatric hospitalizations and antipsychotic trials before clozapine initiation to be associated with greater clozapine response.

Health resource utilization associated with switching to risperidone long-acting injection

OBJECTIVE

Studies have shown oral risperidone and conventional depot antipsychotics decrease direct healthcare costs largely by reducing hospitalization. Our aim was to assess the effect on bed stay of risperidone injection prescribed in normal clinical practice.

METHOD

Patients prescribed risperidone long-acting injection (RLAI) were identified and followed-up for 1 year. Resource use data were collected for 3 years before and for 1 year after the initiation of RLAI. The main outcome measure was bed stay before and after the prescription of RLAI.

RESULTS

Outcome data were available for 250 subjects. Eighty-one subjects (32.4%) completed 1 year's treatment. Days spent in hospital increased from (mean number/patient) 31 in year -3 to 44 in year -2 to 90 in year -1 to 141 in year +1. Direct healthcare costs increased accordingly. Outcome for RLAI continuers was similar to that of discontinuers.

CONCLUSION

Switching to RLAI was associated with a continuation of the trend for increased bed stay and use of healthcare resources.

Cost-effectiveness of add-on lamotrigine therapy in clinical practice

OBJECTIVE

This retrospective study addresses the cost-effectiveness of add-on therapy with lamotrigine in clinical practice.

METHODS

Two years' observational data of 165 patients were used. Seizure frequency, adverse effects and direct medical costs were recorded for the year before and the year after the start of lamotrigine add-on therapy. Therapy effectiveness was measured by: (1) reduction in seizure frequency and (2) retention time. The incremental cost-effectiveness ratio expressed the direct medical cost per patient treated effectively with lamotrigine.

RESULTS

The cost of medication was 492 (95% CI: 399-583) higher after the start of lamotrigine therapy. The extra cost of lamotrigine therapy (622) was partly offset by a reduction of the cost of co-medication (-130; 95% CI: -210 to -50). Overall, the total medical cost was 453 higher in the first year of lamotrigine therapy than in the year before the start of lamotrigine. Lamotrigine was effective in 47% of all the patients, making the resultant incremental cost-effectiveness ratio 954 per year.

DISCUSSION

Add-on therapy of lamotrigine for patients with uncontrolled epilepsy offers improved health outcomes. Lamotrigine therapy is associated with increased cost (453) and an annual incremental cost-effectiveness ratio of 954. These data, together with utility data published in the literature, support the notion that lamotrigine should be considered as an add-on therapy in for patients with refractory epilepsy.

Cost-effectiveness analysis of pharmacological treatments in schizophrenia: critical review of results and methodological issues

OBJECTIVE

To comprehensively review and critically appraise the results and the methodological issues in the cost-effectiveness literature on pharmacological treatments in schizophrenia.

METHODS

Relevant literature published in peer-reviewed journals was identified through a computer search in Medline from 1975 to 2002. Further studies were identified using reference lists and published review articles. Articles included in the review were required to evaluate both costs and clinical outcomes in the same study.

RESULTS

Seventeen articles met all inclusion criteria. Cost-effectiveness analysis (CEA) in schizophrenia spans three types of studies-randomized trial-based studies (six), retrospective cohort-based studies (six) and decision model-based studies (five). Comparing results from CEA across all types of studies in schizophrenia reveals a large ambiguity in the incremental evaluation of newer atypicals. For treatment-resistant patients, clozapine seems to produce cost saving and better outcomes compared to standard neuroleptics. However, there is tremendous uncertainty in the estimates of cost savings and clinical benefits that may prevent decision makers from making optimal policy decisions about insurance coverage and formulary design based on these results. For chronic schizophrenic patients, the results are even more ambiguous. For example, the studies based on trial settings find risperidone to cost more than haloperidol, while studies based on cohort design and decision models find risperidone to be either equivalent or lower in costs than haloperidol.

CONCLUSIONS

Further studies of cost-effectiveness need to be carried out with careful consideration of the limitations of published analyses. There are a variety of theoretical and methodological issues that are important to consider during the development of new decision models in this field.

A review of compliance, depot intramuscular antipsychotics and the new long-acting injectable atypical antipsychotic risperidone in schizophrenia

BACKGROUND

Several oral atypical antipsychotics are available for schizophrenia management. Besides positive and negative symptom control, they may improve cognition. Due to their limited availability as oral agents only, benefits are limited by noncompliance.

METHODS

Using Medline and PsycINFO databases, literature was reviewed to address: (1) factors underlying medication noncompliance; (2) available evidence on efficacy of depot intramuscular (IM) typical antipsychotics; and (3) current knowledge of long-acting atypicals.

RESULTS

Noncompliance remains high due to illness-, treatment-, and clinician-related factors. Compared to oral typicals, atypicals may improve compliance, even though noncompliance remains high. Depot IM typicals are efficacious (reduced relapses and rehospitalizations), but extrapyramidal symptoms are problematic. Available data on long-acting atypical risperidone suggest that it is safe and efficacious.

CONCLUSION

Development of long-acting injectable atypical agents is warranted since noncompliance remains high. Future long-acting IM atypical trials should include outpatient functioning, and preferably be of longer duration to address cost-effectiveness.