Health care resource utilization patterns among patients with Parkinson’s disease psychosis: analysis of Medicare beneficiaries treated with pimavanserin or other-atypical antipsychotics

Pimavanserin (PIM) is the only FDA-approved atypical antipsychotic (AAP) for hallucinations and delusions associated with Parkinson’s disease psychosis (PDP). Comparative real-world analyses demonstrating its benefits are needed. To evaluate health care resource utilization (HCRU) outcomes among PDP patients treated with PIM vs. other-AAPs. Retrospective cohort analysis of Parts A, B, and D claims from 100% Medicare sample from 01 January 2013–31 December 2019 was conducted. PDP Patients initiating (i.e. index date) continuous monotherapy (PIM vs. other-AAPs) for ≥12-months during 01 January 2014–31 December 2018 without 12-months pre-index AAP use were selected after 1:1 propensity score matching (PSM) on 31 variables (sex, race, region, age, and 27 Elixhauser comorbidities). HCRU outcomes included: annual all-cause and psychiatric hospitalization (short-term stay, long-term stay, and SNF-stay [skilled nursing facility]) rates, annual all-cause and psychiatric-ER visit rates, mean per-patient-per-year (PPPY) hospitalizations, and average length of stay (ALOS). PIM and other-AAPs were compared using generalized linear models (GLM) controlled for demographic characteristics, comorbidities, coexisting-dementia, and coexisting insomnia. Of 12,164 PDP patients, 48.41% (<i>n</i> = 5,889) were female, and mean age was 77 (±8.14) years. Among 1:1 matched patients (<i>n</i> = 842 in each), 37.8% (<i>n</i> = 319) on PIM vs. 49.8% (<i>n</i> = 420) on other-AAPs (<i>p</i> &lt; .05) reported ≥1 all-cause hospitalizations, respectively. Specifically, short-term and SNF-stay among PIM patients vs. other-AAPs were: 34% (<i>n</i> = 286) vs. 46.2% (<i>n</i> = 389) and 20.2% (<i>n</i> = 170) vs. 31.8% (<i>n</i> = 267) (<i>p</i> &lt; .05), respectively. Similarly, 9.6% (<i>n</i> = 81) of PIM vs. 14.6% (<i>n</i> = 123) of other-AAPs patients had ≥1 psychiatric hospitalization (<i>p</i> &lt; .05). Furthermore, ≥1 all-cause and psychiatric ER visit among PIM vs. other-AAPs were 61.6% (<i>n</i> = 519) vs. 69.4% (<i>n</i> = 584) and 5.2% (<i>n</i> = 43) vs. 10.2% (<i>n</i> = 86) (<i>p</i> &lt; .05), respectively. PIM also had significantly lower ALOS, and mean PPPY short-term hospitalization and SNF-stays. In this analysis of PDP patients, PIM monotherapy resulted in nearly 12% and 7% lower all-cause hospitalizations and ER visits vs. other-AAPs.

匹莫范色林（Pimavanserin, PIM）是目前唯一经美国食品药品监督管理局（Food and Drug Administration, FDA）批准用于治疗帕金森病精神病（Parkinson’s disease psychosis, PDP）相关幻觉与妄想的非典型抗精神病药（atypical antipsychotic, AAP）。现有研究仍需开展验证其临床获益的真实世界对比分析。本研究旨在评估接受PIM与其他非典型抗精神病药（other-AAPs）治疗的PDP患者的医疗资源利用（health care resource utilization, HCRU）结局。

本研究对2013年1月1日至2019年12月31日的100%美国医保样本的A、B、D部分理赔数据开展回顾性队列分析。纳入2014年1月1日至2018年12月31日期间以索引日期定义为启动持续≥12个月单药治疗（PIM组vs. other-AAPs组）、且索引前12个月未使用过非典型抗精神病药的PDP患者；随后基于31个变量（性别、种族、地区、年龄及27项Elixhauser合并症）进行1:1倾向得分匹配（propensity score matching, PSM）。

本研究的HCRU结局指标包括：年度全因住院与精神科住院（含短期住院、长期住院及专业护理机构（skilled nursing facility, SNF）住院）发生率、年度全因与精神科急诊（emergency room, ER）就诊率、每患者每年（per-patient-per-year, PPPY）平均住院次数及平均住院时长（average length of stay, ALOS）。采用校正了人口学特征、合并症、共存痴呆与共存失眠的广义线性模型（generalized linear models, GLM）对比两组患者的结局差异。

本研究共纳入12164例PDP患者，其中48.41%（n=5889）为女性，平均年龄为77（±8.14）岁。经1:1匹配后，两组各纳入842例患者；其中PIM组37.8%（n=319）、other-AAPs组49.8%（n=420）的患者报告至少1次全因住院（P<0.05）。

具体而言，PIM组与other-AAPs组的短期住院及SNF住院占比分别为34.0%（n=286）vs. 46.2%（n=389）、20.2%（n=170）vs. 31.8%（n=267）（均P<0.05）。同样，PIM组与other-AAPs组分别有9.6%（n=81）、14.6%（n=123）的患者存在至少1次精神科住院（P<0.05）。此外，PIM组与other-AAPs组的至少1次全因急诊与精神科急诊占比分别为61.6%（n=519）vs. 69.4%（n=584）、5.2%（n=43）vs.10.2%（n=86）（均P<0.05）。PIM组的平均住院时长、PPPY短期住院次数及SNF住院次数亦显著低于other-AAPs组。

本针对PDP患者的分析显示，与other-AAPs单药治疗相比，PIM单药治疗可使全因住院率与急诊就诊率分别降低近12%与7%。