Why and how antipsychotic drugs are used in 40 Sydney nursing homes.

BACKGROUND: For decades there has been a high use of antipsychotic medication in nursing homes, though recently the use of typical antipsychotics has reduced while use of atypical antipsychotic medication has increased. The Australian government subsidises use of the latter in management of schizophrenia, and since April 2005 has subsidised use of risperidone (but still not the other atypicals) in cases of dementia with behavioural disturbance. This study was designed to examine the pattern of, and reasons for, antipsychotic use in a range of Sydney nursing homes.

METHODS: Clinical files and medication cards in 40 Sydney nursing homes were examined in late 2003 by a research nurse, who recorded documented diagnoses, blood glucose levels and use of medication in the previous 4 weeks.

RESULTS: Antipsychotics were prescribed for 577 (25.1%) of the 2302 residents. Of these, 114 had schizophrenia. Of the 2302, 6.1% and 15.6%, respectively, had documented diagnoses of schizophrenia and/or diabetes. Of those with schizophrenia, 13.6% had diabetes. Two-thirds of those given antipsychotics had dementia or cerebral disease and not schizophrenia. Two-thirds of the antipsychotic prescriptions for residents with schizophrenia, and also for those without, were for atypicals (n = 200 olanzapine, 174 risperidone, 19 quetiapine). Blood glucose measurements had been recorded in less than 45%.

CONCLUSIONS: In Sydney in 2003, most (80%) of the nursing home residents for whom antipsychotics were prescribed did not have a diagnosis of schizophrenia. The records suggested that insufficient attention had been given to the possibility that use of certain antipsychotics can be associated with impaired glucose metabolism.