Evaluation of mortality in users of pimavanserin compared with other atypical antipsychotics in patients with parkinson’s disease psychosis

Abstract

INTRODUCTION: Pimavanserin is the only antipsychotic medication approved in the USA to specifically treat hallucinations and delusions associated with Parkinson's disease psychosis (PDP).

OBJECTIVE: To compare mortality risk in patients with PDP after initiation of pimavanserin or comparator atypical antipsychotics in an overall PDP cohort and in a subcohort of patients residing in long-term care or skilled nursing facilities (LTC/SNFs).

METHODS: This cohort study identified patients aged ≥ 65 years with PDP initiating pimavanserin or a comparator antipsychotic in US Medicare claims (2016-2021). Cox proportional hazards models were used to estimate hazard ratios (HRs) comparing all-cause mortality in the propensity score-matched treatment groups. Cumulative incidence curves, time period-specific relative risk, and risk difference estimates evaluated risk over time.

RESULTS: In this follow-up analysis, we identified 4384 pimavanserin initiators and 28,042 comparator initiators in the overall PDP cohort, and 921 pimavanserin initiators and 7963 comparator initiators in the LTC/SNF subcohort. After matching, the overall PDP cohort had 4381 patients in each treatment group, and the LTC/SNF subcohort had 905 patients in each group. The matched HR for mortality (pimavanserin versus comparator) was 0.76 (95% CI 0.68-0.85) in the overall PDP cohort and 0.90 (95% CI 0.74-1.10) in the LTC/SNF subcohort. In the overall PDP cohort, time period-specific relative risks and risk differences showed that pimavanserin initiators had a lower risk of mortality throughout the first 365 days of follow-up.

CONCLUSION: In the overall PDP cohort, mortality risk was lower among pimavanserin initiators than comparator antipsychotic initiators.