Prescription and Underprescription of Clozapine in Dutch Ambulatory Care

Evaluation of a collaborative care program for patients with treatment-resistant schizophrenia: Protocol for a multiple case-study. (Preprint)

Background

Approximately one-third of all patients with schizophrenia are treatment resistant. Worldwide, undertreatment with clozapine and other effective treatment options exist for people with treatment-resistant schizophrenia (TRS). In this respect, it appears that regular health care models do not optimally fit this patient group. The Collaborative Care (CC) model has proven to be effective for patients with severe mental illness, both in primary care and in specialized mental health care facilities. The key principles of the CC model are that both patients and informal caregivers are part of the treatment team, that a structured treatment plan is put in place with planned evaluations by the team, and that the treatment approach is multidisciplinary in nature and uses evidence-based interventions. We developed a tailored CC program for patients with TRS.

Objective

In this paper, we provide an overview of the research design for a potential study that seeks to gain insight into both the process of implementation and the preliminary effects of the CC program for patients with TRS. Moreover, we aim to gain insight into the experiences of professionals, patients, and informal caregivers with the program.

Methods

This study will be underpinned by a multiple case study design (N=20) that uses a mixed methods approach. These case studies will focus on an Early Psychosis Intervention Team and 2 Flexible Assertive Community treatment teams in the Netherlands. Data will be collected from patient records as well as through questionnaires, individual interviews, and focus groups. Patient recruitment commenced from October 2020.

Results

Recruitment of participants commenced from October 2020, with the aim of enrolling 20 patients over 2 years. Data collection will be completed by the end of 2023, and the results will be published once all data are available for reporting.

Conclusions

The research design, framed within the process of developing and testing innovative interventions, is discussed in line with the aims of the study. The limitations in clinical practice and specific consequences of this study are explained.

International Registered Report Identifier (IRRID)

DERR1-10.2196/35336

[Clozapine in the Treatment of Schizophrenic Psychosis: Patient Characteristics and Antipsychotic Combinations in One Cohort at a Psychiatric Care Hospital]

BACKGROUND

In many studies, clozapine has been reported to have superior effectiveness compared to other antipsychotics. So far there is little systematic data on the practice of clozapine prescription and characteristics of patients treated.

METHOD

Retrospective evaluation of all 392 treatment courses of inpatients with schizophrenic psychoses during one year. Detailed analysis of the patients treated with clozapine including the dosages and additional psychotropic medication.

RESULT

Patients treated with clozapine showed a higher disease severity than patients without clozapine. They received more frequently pharmacological combination therapies, which in some cases significantly contradicted the current guideline recommendations.

CONCLUSION

The results underline the pronounced disease severity of patients receiving clozapine treatment and substantiate evidence from the literature on the limited implementation of guidelines in prescribing practice. The study carried out serves as a pilot survey of a multicenter research project on the practice of prescribing clozapine in psychiatric hospitals in different German regions.

Delegating Clozapine Monitoring to Advanced Nurse Practitioners: An Exploratory, Randomized Study to Assess the Effect on Prescription and Its Safety

To test whether: (1) psychiatrists will prescribe clozapine more often if they can delegate the monitoring tasks to an advanced nurse practitioner (ANP), (2) clozapine monitoring by an ANP is at least as safe as monitoring by a psychiatrist. Patients from 23 Dutch outpatient teams were assessed for an indication for clozapine. ANPs affiliated to these teams were randomized to Condition A: clozapine monitoring by an ANP, or Condition B: monitoring by the psychiatrist. The safety of monitoring was evaluated by determining whether the weekly neutrophil measurements were performed. Staff and patients were blinded regarding the first hypothesis. Of the 173 patients with an indication for clozapine at baseline, only seven in Condition A and four in Condition B were prescribed clozapine (Odds Ratio = 2.24, 95% CI 0.61–8.21; p = 0.225). These low figures affected the power of this study. When we considered all patients who started with clozapine over the 15-month period (N = 49), the Odds Ratio was 1.90 (95% CI 0.93–3.87; p = 0.078). With regard to the safety of the monitoring of the latter group of patients, 71.2% of the required neutrophil measurements were performed in condition A and 67.3% in condition B (OR = 0.98; CI = 0.16–3.04; p = 0.98). Identifying patients with an indication for clozapine does not automatically lead to improved prescription rates, even when an ANP is available for the monitoring. Clozapine-monitoring performed by an ANP seemed as safe as that by a psychiatrist.

Use of cardiovascular and antidiabetic drugs before and after starting with clozapine versus other antipsychotic drugs: a Dutch database study

Reports of decreased mortality among patients with schizophrenia who use clozapine may be biased if clozapine is prescribed to relatively healthy patients and if intensive monitoring during its use prevents (under-treatment of) somatic disorder. We aimed to assess whether there is a difference in: (1) somatic comorbidity between patients who start with clozapine and those who start with other antipsychotics and (2) prescribed somatic medication, between patients using clozapine and those using olanzapine. Cohort study based on insurance claims (2010-2015). After selecting new users of antipsychotics and those who subsequently switched to clozapine (N = 158), aripiprazole (N = 295), olanzapine (N = 204) or first-generation antipsychotics (N = 295), we compared the clozapine starters to others on cardiovascular or diabetic comorbidity. Those using clozapine and olanzapine were compared on new prescriptions for cardiovascular or antidiabetic drugs. The ORadj of cardiovascular or diabetic comorbidity among other starters compared with clozapine starters was 0.77 [95% confidence interval (CI): 0.43-1.39], that is, a nonsignificantly increased prevalence associated with clozapine was found. Users of clozapine received significantly more new prescriptions for cardiovascular or antidiabetic medication (ORadj: 2.70, 95% CI: 1.43-5.08). Starters with clozapine were not cardiovascular/metabolic healthier than starters with other antipsychotics. During its use, they received more somatic treatment.