Initiation and continuation of antipsychotic medicines in older people following non-psychiatric hospital admission.

Background Internationally, antipsychotics are frequently initiated during hospital admission for older patients and use often continues post-discharge without indication. We located no Australian studies on this topic. Objective to identify the hospital admissions (excluding psychosis) associated with antipsychotic initiation and continuation in older Australians. Setting Australian Government Department of Veterans' Affairs. Method Retrospective analysis of administrative claims data for people admitted to hospital from 1 January 2014 to 31 December 2014, aged ≥ 65 years, who were antipsychotic naïve. Main outcome measure number of admissions associated with antipsychotic initiation, and the major diagnosis groups for these admissions. Where antipsychotics were initiated, we determined the time to cessation of antipsychotics after discharge. Results There were 142,009 hospital admissions for 66,415 people with a median age of 86 years. 921 (0.65%) admissions were associated with antipsychotic initiation, most commonly where the primary diagnoses were for mental and behavioural disorders excluding psychosis (17.8%) and injuries (16%). Fourteen percent of antipsychotic initiations were for primary diagnoses of delirium or dementia. When secondary diagnoses were considered, 55% of antipsychotic initiations were associated with delirium, dementia or both. The median duration of use among people who used antipsychotics was 132 days, and 40% continued use until death or one year follow-up. Conclusion Initiation of antipsychotics during hospital admissions was not frequent in this Australian population. Amongst those who did initiate antipsychotics, for almost half no diagnosis corresponding with an approved indication for use was recorded and long-term use of up to one year was common.