Persistence of Antipsychotic Treatment in Elderly Dementia Patients: A Retrospective, Population-Based Cohort Study

BACKGROUND: Antipsychotics are commonly used to manage behavioral and psychological symptoms of dementia. Concerns over their safety and efficacy in this role have resulted in antipsychotics typically being recommended for short-term usage only when used among dementia patients. However, there is little work examining the duration of antipsychotic treatment in the elderly dementia patient population. OBJECTIVE: To determine the persistence of use of antipsychotics in elderly dementia patients and the role of dose on therapy duration. METHODS: A retrospective, population-based cohort study using administrative data, including dispensing records from a provincial public drug program, from Ontario, Canada between 2009 and 2012. Elderly dementia patients newly initiated onto antipsychotics were followed until drug discontinuation, death, 2-year follow-up, or end of study. Competing risk analysis was performed to determine time to discontinuation, stratified by categories of initial dose. RESULTS: After 2 years 49.1 % of the cohort (N = 22,927 of 46,695) had discontinued treatment. When stratified by dose, the high-dose group (51.1 % discontinued) discontinued more frequently than the medium- (48.7 % discontinued) and low- (47.5 % discontinued) dose groups (p < 0.0001). CONCLUSION: Approximately half of elderly dementia patients treated with antipsychotics discontinue within 2 years, with those on higher doses more likely to discontinue. However, the number of patients remaining on therapy represents a serious public health concern.