Patient factors associated with receipt of combination antipsychotic drug therapy in the treatment of schizophrenia

Optimisation of prescription in patients with long-term treatment-resistant schizophrenia

OBJECTIVE

The aim of this clinical review was to investigate the effectiveness and safety of the practice of antipsychotic poly-pharmacy (AP) in the long-term management of hospitalised patients with insufficient response to antipsychotic monotherapy.

METHOD

The databases Medline, PsycINFO, Embase and Scopus were searched. Studies were required to include inpatients with long-term, treatment-resistant schizophrenia on maintenance AP. The search was restricted to systematic review studies.

RESULTS

The review yielded four studies of interest that showed no categorical advantage for maintenance AP for the population of interest. However, clozapine combination faired marginally well. Particular weaknesses of the present literature are low number of participants, and inadequate monitoring of potential adverse effects. The evidence on the risks and benefits of maintenance AP is not generally considered adequate to warrant a recommendation for its use in routine clinical practice in psychiatry.

CONCLUSIONS

This review provides a synthesis of the evidence on the maintenance use of AP for hospitalised patients with long-term, treatment-resistant schizophrenia. The results show both no support for AP with some marginal benefit for clozapine combination therapy, and methodological weaknesses of the included studies. These findings have clinical implications for treatment decisions and suggest that sufficiently powered studies are needed.

Conformance to schizophrenia treatment guidelines in North West-Bank, Palestine: focus on antipsychotic dosing and polytherapy

BACKGROUND

Analysis of the prescribing patterns of antipsychotic drugs can improve therapeutic outcomes. The purpose of this study was to evaluate the prescribing pattern of antipsychotics and its conformance to international treatment guidelines.

METHODS

A cross sectional study at primary psychiatric centers was carried out. Patients' medical files were used to obtain demographic, medication and clinical information. International guidelines for schizophrenia were used to create conformance indicators. All statistical analyses were conducted using Statistical Package for Social Sciences.

RESULTS

250 patients were included in this study. A total of 406 antipsychotic agents were used; 348 (85.7%) were first generation antipsychotics (FGA). The prevalence of antipsychotic combination was 50.4% (n=126). There was no significant difference in positive (p=0.3), negative (p=0.06) and psychopathology (p=0.5) scores of schizophrenia symptoms among patients on monotherapy versus those on antipsychotic combination. Furthermore, no significant difference was observed in the annual cost of antipsychotic monotherapy versus combination therapy. One hundred and five patients (42%) were using optimum dose of (300 - 600 mg CPZeq) while the remaining were using sub or supra therapeutic doses. Analysis showed that use of depot, use of anticholinergic agents and increasing amount of total CPZeq were significant factors associated with antipsychotic combination.

CONCLUSIONS

This study indicated that antipsychotic prescribing was not in conformance with international guidelines with respect to maintenance dose and combination therapy. Type of antipsychotic treatment regimen, combination versus monotherapy, was not associated with better clinical or economic outcome.

Payer types associated with antipsychotic polypharmacy in an ambulatory care setting

Objectives

Antipsychotic polypharmacy is increasingly prescribed despite little documented evidence of a therapeutic benefit. There is also a limited understanding of the role that health insurance plays on the prevalence of antipsychotic polypharmacy. This study was undertaken to investigate the relationship between antipsychotic polypharmacy and individuals' intended source of payment in a US national sample of ambulatory care patients.

Methods

The study combined 2002, 2003 and 2004 data from the National Ambulatory Medical Care Survey (NAMCS) among adults seeking outpatient-based physician medical care services in the USA. We investigated characteristic differences among patients who were prescribed multiple antipsychotics versus individuals receiving only a single antipsychotic medication. Multivariable logistic regression examined the association between antipsychotic polypharmacy and patients' primary payment type classified as private insurance, Medicaid, Medicare or other (primarily out-of-pocket) payment type.

Key findings

Use of more than one antipsychotic agent was recorded in 68 of 830 (8.2%) outpatient physician visits in the 3-year period 2002–2004. Among the payer types studied, Medicaid payment status was correlated with increased risk of antipsychotic polypharmacy (odds ratio 2.7, 95% confidence interval 1.1–6.7).

Conclusions

Insurance status was associated with antipsychotic polypharmacy among non-institutionalized US residents prescribed antipsychotic medications. Patients reporting Medicaid as their primary payer were nearly three times as likely to be prescribed multiple antipsychotic drugs, potentially increasing their risk of adverse side effects as well as greater taxpayer burden. Future research should determine whether these trends continued after 2004 and to determine the costs of treating patients in the public sector with multiple antipsychotic drugs, a common scenario despite financial pressures and uncertain medical benefit.