The Modified Functional Status Questionnaire for Assessing Patients with Parkinson's Disease Psychosis Treated with Pimavanserin: A Post Hoc Analysis.

INTRODUCTION

Over half of patients with Parkinson's disease experience psychosis (PDP) symptoms over the course of their disease. In addition to significantly impacting patients' health-related quality of life and cognitive abilities, these symptoms impact patients' activities of daily living (ADLs) and overall functional status. Clinical assessment of how psychosis impacts these measures is crucial; however, few studies have assessed functional status among patients with PDP. A previous phase 4 study assessing the impact of pimavanserin on ADLs in patients with PDP demonstrated that a modified version of the Functional Status Questionnaire (mFSQ) could be used for this purpose. This post hoc analysis aimed to demonstrate the utility of the mFSQ as a patient-reported outcomes tool and to expand on initial study findings by showing the impact of pimavanserin on ADLs and functional status for each mFSQ subscale.

METHODS

An analysis of mFSQ data was conducted on patients with PDP treated with pimavanserin. This analysis evaluated the least-squares mean (LSM) change from baseline to week 16 on the mFSQ by subscale (basic ADL, intermediate ADL, psychological function, quality of interaction, and social activity). Pearson's correlation was used to assess the relationship between results from the mFSQ and the well-established Schwab and England ADL scale.

RESULTS

In this assessment (n = 29), treatment with pimavanserin was associated with improvements on all 5 domains of the mFSQ, highlighting a broad improvement in ADLs and function. The greatest LSM (SE) improvement was seen in the social activity subscale [25.8 (7.52); 95% CI 10.2-41.5; p = 0.0026]. The mFSQ results demonstrated positive correlations with patient- and caregiver-rated Schwab and England ADL scales.

CONCLUSION

This analysis provides additional information about the impact of treatment with pimavanserin on specific mFSQ subscales. Additionally, the mFSQ was significantly correlated with the patient- and the caregiver-rated Schwab and England ADL scales.