Antipsychotic prescribing and its correlates in New Zealand

Abstract

Objectives: Antipsychotics are the cornerstone of schizophrenia management. There is substantial literature on their efficacy and optimal use. Doubts remain, however, regarding the translation of this knowledge into day-to-day practice. This study aimed to investigate antipsychotic prescribing in three New Zealand regions and its relationship to clinical guidelines and patient characteristics. Methods: We studied 451 patients discharged from inpatient units with a diagnosis of schizophrenia or a related disorder (International Classification of Disease, version 10) between July 2009 and December 2011. Available information included patient demography, legal status, prescribed medications, duration of index admission and prescriber’s country of postgraduate training and years of postgraduate experience. Results: There was a high rate (33.7%) of multiple antipsychotic prescription, and lower than expected clozapine use (20%); Maori were prescribed clozapine more frequently than non-Maori (24% vs. 13%, respectively). Compulsory treatment was associated with more use of injectable medication and increased length of stay in hospital. Clinician characteristics did not significantly influence prescribing. Conclusions: Observed prescribing practice aligned with existing guidelines except for antipsychotic polypharmacy and clozapine under-utilisation.