Antipsychotic polypharmacy among patients admitted to a geriatric psychiatry unit

This study describes the prevalence of antipsychotic polypharmacy in patients admitted to a geriatric psychiatry unit, compares polypharmacy by psychiatric diagnosis, explores predictors of polypharmacy, and examines changes in antipsychotic polypharmacy from baseline to discharge.

A retrospective examination was made of patients admitted to an inpatient geriatric psychiatry ward between 2006 and 2010. All patients with a diagnosis of schizophrenia, bipolar disorder, or dementia prescribed a regularly scheduled antipsychotic for at least 1 month prior to admission were included.

Of the 416 patients meeting selection criteria, nearly 13% were prescribed antipsychotic polypharmacy at the time of admission. Quetiapine was the antipsychotic most commonly involved in polypharmacy. By discharge, the rate of antipsychotic polypharmacy had decreased to 8% (X=4.74, df=1, p=0.03). Patients with a history of a severe mental illness were significantly more likely to have been prescribed antipsychotic polypharmacy compared with those with only a diagnosis of dementia (X=14.67, df=1, p=<0.001). Living situation and psychiatric diagnosis were significant predictors of antipsychotic polypharmacy.

Older adults admitted to a geriatric psychiatry ward on a scheduled antipsychotic were commonly prescribed more than one antipsychotic. This was most likely in patients living in a facility (e.g., assisted living, skilled nursing, long-term care) and in those patients with a severe mental illness. A better understanding of the efficacy and safety of antipsychotic polypharmacy in older adults, especially those with dementia, is necessary in order to use these medications rationally.