Falls and Fractures in Patients with Parkinson's Disease-Related Psychosis Treated with Pimavanserin vs Atypical Antipsychotics: A Cohort Study

Falls and Fractures among Nursing Home Residents Treated with Pimavanserin versus Other Atypical Antipsychotics: Analysis of Medicare Beneficiaries with Parkinson's Disease Psychosis

BACKGROUND

Reducing falls and fractures remains an important clinical goal in managing older residents with Parkinson's disease psychosis (PDP) in long-term care/nursing home (LTC/NH) settings.

OBJECTIVES

This analysis examined risk of all-cause falls or fractures among PDP residents on continuous monotherapy with pimavanserin (PIM) versus (i) other atypical antipsychotics (AAPs) [quetiapine (QUE), risperidone (RIS), olanzapine (OLA), aripiprazole (ARI)] and (ii) QUE.

METHODS

A retrospective analysis of parts A, B, and D claims from a 100% Medicare sample (2013-2019) in LTC/NH settings was conducted. LTC/NH residents in the USA initiating continuous monotherapy (PIM versus other AAPs; PIM versus QUE) for ≥ 6 months between 01 January 2014 and 31 December 2018 were 1:1 propensity score matched (PSM) on 31 variables (age, sex, race, region, and 27 Elixhauser comorbidities). Outcomes included three measures: risks of falls only, fractures only, and falls/fractures during 6-months follow-up. Demographic characteristics were described using chi-square and t-tests. Generalized linear models were used to assess difference in risks of falls/fractures.

RESULTS

Of 7187 residents, 47.59% (n = 3420) were female and mean age was 78.8 (± 7.75) years. In total, 14% (n = 1005) were on PIM and 86% (n = 6182) were on other AAPs. After PSM, falls only among PIM residents (n = 1005) was 4.58% (n = 46) versus 7.66% (n = 77) for other AAPs (n = 1005) [relative risk (RR) = 0.63 (0.46, 0.86), p < 0.05] and 8.26% (n = 83) for QUE (n = 1005) residents (p < 0.05). Fractures only among PIM residents was 1.39% (n = 14) compared with 2.09% (n = 21) for other AAPs (p = 0.31) and 1.89% (n = 19) for QUE (p = 0.49), respectively. Taken together, falls/fractures among PIM residents were 5.67% (n = 57) versus 9.05% (n = 91) for other AAPs [RR = 0.63 (0.46, 0.86), p < 0.05] and 9.55% (n = 96) for QUE (p < 0.05), respectively.

CONCLUSIONS

In this analysis of LTC/NH residents with PDP, PIM had a 37% and 41% lower risk of all-cause falls/fractures versus other AAPs and versus QUE, respectively.

Healthcare resource utilization among nursing home residents with Parkinson's disease psychosis: an analysis of Medicare beneficiaries treated with pimavanserin or other-atypical antipsychotics

Aim: Real-world healthcare resource use (HCRU) burden among patients with Parkinson's disease psychosis (PDP) treated with pimavanserin (PIM) versus other atypical antipsychotics (other-AAPs) including quetiapine (QUE) in long term care (LTC) and nursing home (NH) settings are lacking. This analysis examines HCRU differences among residents in LTC/NH settings who initiate PIM versus QUE or other-AAPs. Methods: A retrospective analysis of LTC/NH residents with PDP from the 100% Medicare claims between 1 April 2015 and 31 December 2021 was conducted. Treatment-naive residents who initiated ≥6 months continuous monotherapy with PIM or QUE or other-AAPs between 04/01/16 and 06/30/2021 were propensity score matched (PSM) 1:1 using 31 variables (age, sex, race, region and 27 Elixhauser comorbidity characteristics). Post-index (i.e., 6 months) HCRU outcomes included: proportion of residents with ≥1 all-cause inpatient (IP) hospitalizations and emergency room (ER) visits. HCRU differences were assessed via log binomial regression and reported as relative risk ratios (RR) and 95% confidence intervals after controlling for dementia, insomnia and index year. Results: From a total of PIM (n = 1827), QUE (n = 7770) or other-AAPs (n = 9557), 1:1 matched sample (n = 1827) in each cohort were selected. All-cause IP hospitalizations (PIM [29.8%]) versus QUE [36.7%]) and ER visits (PIM [47.3%] versus QUE [55.8%]), respectively, were significantly lower for PIM. PIM versus QUE cohort also had significantly lower RR for all-cause IP hospitalizations and ER visits, respectively, (IP hospitalizations RR: 0.82 [0.75. 0.9]; ER visits RR: 0.85 [0.8. 0.9]). PIM versus other-AAPs also had lower likelihood of HCRU outcomes. Conclusion: In this analysis, LTC/NH residents on PIM monotherapy (versus QUE) had a lower likelihood of all-cause hospitalizations (18%) and ER (15%) visits. In this setting, PIM also had lower likelihood of all-cause HCRU versus other-AAPs.

Brief commentary: Under-recognition of underuse of clozapine in treating psychotic symptoms in Parkinson's disease

Clozapine is an important drug in the treatment of Parkinson's disease (PD). It has proven efficacy in treating PD psychosis without worsening motor function, as well as in treating tremor refractory to L-Dopa, yet it is severely underused in the United States. Unlike the situation of treatment resistant schizophrenia, this underuse is underrecognized.

Retrospective analyses evaluating the mortality risk associated with pimavanserin or other atypical antipsychotics in patients with Parkinson disease psychosis

Introduction

Parkinson's disease (PD) is associated with increased mortality risk (MR), reflecting progression of motor and nonmotor symptoms. PD psychosis (PDP), a common nonmotor symptom, increases with prolonged disease and elevates the MR of PD even further. Pimavanserin is the only FDA-approved treatment for PDP. This review summarizes real-world evidence around the MR of patients with PDP treated with pimavanserin versus off-label atypical antipsychotics.

Methods

A PubMed search was conducted using the following search terms: pimavanserin AND antipsychotic AND mortality AND Parkinson's disease AND psychosis. Inclusion criteria specified the entry of retrospective, observational, and open-label studies comparing pimavanserin to atypical antipsychotics or untreated controls.

Results

A total of 10 of the 32 articles met inclusion criteria. Among five comparisons of pimavanserin with atypical antipsychotics, two were large (n = 21,719; n = 21,975), representative, Medicare-database studies, which demonstrated comparable or lower all-cause pimavanserin MR. Among three pimavanserin versus control studies, two reported lower or comparable pimavanserin MR and one, long-term care study reported higher MR for pimavanserin versus non-pimavanserin treated patients with unknown PDP status. Two open-label extensions reported pimavanserin mortality rates of 6.45 and 18.8 deaths per 100 patient-years, which are comparable to, or lower than, mortality rates for PD, PDP, and other atypical antipsychotics. Most studies (70 %; 7 of 10) demonstrated pimavanserin's MR was lower than or similar to other atypical antipsychotics or untreated controls.

Conclusions

Pimavanserin did not increase the MR in PDP. Pimavanserin's MR appears to be comparable to or lower than other atypical antipsychotics prescribed for PDP, including quetiapine.

Performance of a Claims-Based Frailty Proxy Using Varying Frailty Ascertainment Lookback Windows

BACKGROUND

Frailty is an aging-related syndrome of reduced physiological reserve to maintain homeostasis. The Faurot frailty index has been validated as a Medicare claims-based proxy for predicting frailty using billing information from a user-specified ascertainment window.

OBJECTIVES

We assessed the validity of the Faurot frailty index as a predictor of the frailty phenotype and 1-year mortality using varying frailty ascertainment windows.

RESEARCH DESIGN

We identified older adults (66+ y) in Round 5 (2015) of the National Health and Aging Trends Study with Medicare claims linkage. Gold standard frailty was assessed using the frailty phenotype. We calculated the Faurot frailty index using 3, 6, 8, and 12 months of claims prior to the survey or all-available lookback. Model performance for each window in predicting the frailty phenotype was assessed by quantifying calibration and discrimination. Predictive performance for 1-year mortality was assessed by estimating risk differences across claims-based frailty strata.

RESULTS

Among 4253 older adults, the 6 and 8-month windows had the best frailty phenotype calibration (calibration slopes: 0.88 and 0.87). All-available lookback had the best discrimination (C-statistic=0.780), but poor calibration. Mortality associations were strongest using a 3-month window and monotonically decreased with longer windows. Subgroup analyses revealed worse performance in Black and Hispanic individuals than counterparts.

CONCLUSIONS

The optimal ascertainment window for the Faurot frailty index may depend on the clinical context, and researchers should consider tradeoffs between discrimination, calibration, and mortality. Sensitivity analyses using different durations can enhance the robustness of inferences. Research is needed to improve prediction across racial and ethnic groups.

Parkinson's disease psychosis management: an evidence based, experience informed, pragmatic approach

INTRODUCTION

Psychotic symptoms in people with Parkinson's disease (PD) have attracted increasing. Recommendations on treating psychosis often fail to take into account what psychotic symptoms require treatment, which has been complicated by the increasing number of reports documenting the frequency of 'minor' hallucinations.

AREAS COVERED

This article focuses both on the phenomenology of psychotic symptoms and their management.

EXPERT OPINION

Understanding the nature and implications of the types of psychotic symptoms in PD is the key to proper treatment. Evidence and experience-based data on the effect of anti-psychotic medications will be reviewed and how the various clinical settings should determine the treatment approach. The evidence base consists of all reported blinded trials recorded in PubMed and the experience-based studies are those chosen by the author from PubMed as illustrative. Specific recommendations for the treatment of psychosis will be listed for specific situations. Pimavanserin is the first-line choice for mild symptoms; quetiapine for symptoms that require improvement in a short period and clozapine for urgent problems or those which fail the other approaches.

Risk of long-term care admissions among Medicare beneficiaries treated with pimavanserin or quetiapine for Parkinson's disease psychosis in USA: a retrospective administrative claims database analysis

Aim: Risk of long-term care (LTC) admission (LTCA) associated with atypical antipsychotic (AAP) use among patients with Parkinson's disease psychosis (PDP) is a major concern. However, no comparative studies have examined the differences in risk of LTC admissions between pimavanserin (PIM), the only FDA-approved AAP for PDP, and other off-label AAPs including quetiapine (QUE). Objective: To examine all-cause LTCA rates and risk among PDP patients treated with AAPs such as QUE or PIM. Methods: Analysis of Parts A, B and D claims (100% Medicare sample; 2013-2019) of Medicare beneficiaries with PDP that initiate ≥12-month continuous PIM or QUE monotherapy from 1 January 2014 to 31 December 2018 (i.e., index date) without any AAP use in the 12-month pre-index period was conducted. Outcome assessments among 1:1 propensity score-matched (31 variables - age, sex, race, region and 27 Elixhauser comorbidities) beneficiaries on PIM versus QUE included risk of all-cause skilled nursing facility stays (SNF-stays), LTC-stays, and overall LTCA (i.e., SNF-stays or LTC-stays). All-cause LTCA rates and LTCA risk were compared using logistic regression and cox proportional hazards models, respectively, controlling for demographics, comorbidities and co-existing-dementia or insomnia. Results: Of the matched sample (n = 842 for each group) from total sample (n = 9652), overall all-cause LTCA and SNF-stay rates were 23.2 and 20.2% for PIM versus 33.8 and 31.4% for QUE, respectively (p < 0.05, for each). Hazard ratio (95% CI) for risk of SNF-stay and overall LTCA was 0.78 (0.61, 0.98) and 0.80 (0.66, 0.97), respectively, for PIM versus QUE beneficiaries (p < 0.05, for each). Conclusion: The 20% lower risk of LTCA (i.e., greater delay) with PIM versus QUE in this analysis may suggest that PIM should be started early for the treatment of PDP.

Translation of a Claims-Based Frailty Index From the International Classification of Diseases, Ninth Revision, Clinical Modification to the Tenth Revision

The Faurot frailty index (FFI) is a validated algorithm that uses enrollment and International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM)-based billing information from Medicare claims data as a proxy for frailty. In October 2015, the US health-care system transitioned from the ICD-9-CM to the International Classification of Diseases, Tenth Revision, Clinical Modification (ICD-10-CM). Applying the Centers for Medicare and Medicaid Services General Equivalence Mappings, we translated diagnosis-based frailty indicator codes from the ICD-9-CM to the ICD-10-CM, followed by manual review. We used interrupted time-series analysis of Medicare data to assess the comparability of the pre- and posttransition FFI scores. In cohorts of beneficiaries enrolled in January 2015-2017 with 8-month frailty look-back periods, we estimated associations between the FFI and 1-year risk of aging-related outcomes (mortality, hospitalization, and admission to a skilled nursing facility). Updated indicators had similar prevalences as pretransition definitions. The median FFI scores and interquartile ranges (IQRs) for the predicted probability of frailty were similar before and after the International Classification of Diseases transition (pretransition: median, 0.034 (IQR, 0.02-0.07); posttransition: median, 0.038 (IQR, 0.02-0.09)). The updated FFI was associated with increased risks of mortality, hospitalization, and skilled nursing facility admission, similar to findings from the ICD-9-CM era. Studies of medical interventions in older adults using administrative claims should use validated indices, like the FFI, to mitigate confounding or assess effect-measure modification by frailty.

Hospitalization and the Risk of Initiation of Antipsychotics in Persons With Parkinson's Disease

OBJECTIVES

The use of antipsychotics in persons with Parkinson's disease (PD) is common, although their use may aggravate the symptoms of PD. Clozapine and quetiapine are the only antipsychotics recommended in PD treatment guidelines. Information on factors associated with initiation of antipsychotics is needed. We investigated whether recent hospitalization is associated with initiation of antipsychotics in persons with PD, and whether discharge diagnoses differ between those who had antipsychotics initiated and those who did not.

DESIGN

Nested case-control study in the nationwide register-based Finnish Study on Parkinson's disease (FINPARK).

SETTING AND PARTICIPANTS

The FINPARK study includes 22,189 persons who received an incident, clinically verified PD diagnosed during 1996-2015 and were community-dwelling at the time of diagnosis. The cases were 5088 persons who had antipsychotics initiated after PD diagnosis, identified with 1-year washout. The controls were 5088 age-, sex-, and time from PD diagnosis-matched persons who did not use antipsychotics on the matching date (antipsychotic purchase date). Recent hospitalization was defined as discharge in the 2-week period preceding the matching date.

METHODS

Associations were investigated with conditional logistic regression.

RESULTS

Quetiapine was the most commonly initiated antipsychotic (72.0% of cases), followed by risperidone (15.0%). Clozapine was initiated rarely (1.1%). Recent hospitalization associated strongly with antipsychotic initiation [61.2% of cases and 14.9% of controls, odds ratio (OR) 9.42, 95% CI 8.33-10.65], and longer hospitalizations were more common among cases. PD was the most common discharge diagnosis category (51.2% of hospitalized cases and 33.0% controls), followed by mental and behavioral disorders (9.3%) and dementia (9.0%) among cases. Antidementia and other psychotropic medication use were more common among cases.

CONCLUSIONS AND IMPLICATIONS

These results suggest that antipsychotics were initiated because of neuropsychiatric symptoms or aggravation of those symptoms. Antipsychotics should be prescribed after careful consideration to avoid adverse effects in persons with Parkinson's disease.

Mortality in Patients with Parkinson's Disease-Related Psychosis Treated with Pimavanserin Compared with Other Atypical Antipsychotics: A Cohort Study

INTRODUCTION

Pimavanserin is approved in the USA to treat hallucinations and delusions associated with Parkinson's disease psychosis (PDP).

OBJECTIVES

We evaluated mortality in patients with PDP after initiation of pimavanserin or comparator atypical antipsychotics, overall, over time, and across subgroups.

METHODS

A cohort of patients aged ≥65 years in the USA with PDP newly initiating pimavanserin or a comparator atypical antipsychotic (clozapine, quetiapine, risperidone, olanzapine, aripiprazole, brexpiprazole) was identified in 2016-2019 Medicare claims data. All-cause mortality in the propensity score-matched treatment groups was compared with hazard ratios (HRs) and 95% confidence intervals (CIs) estimated with Cox-proportional hazards models. Cumulative incidence curves and time period-specific models evaluated risk over time. Subgroup and sensitivity analyses were performed, including a sub-cohort of long-term care (LTC) or skilled nursing facility (SNF) residents.

RESULTS

We identified 2892 pimavanserin initiators and 19,083 comparator initiators (overall 47% female, mean age = 80.9 years, LTC/SNF residents = 30%). Before matching, pimavanserin users had fewer severe comorbidities and more anti-Parkinson medication use than comparators. Matching resulted in 2891 patients in both groups, and all covariates were well balanced. In the matched cohort, the HR for mortality for pimavanserin versus comparator was 0.78 (95% CI 0.67-0.91), with the lowest time period-specific HRs in the first 180 days. Hazard ratios were similar across sensitivity analyses and subgroups. In LTC/SNF residents, the HR was 0.78 (95% CI 0.60-1.01).

CONCLUSION

The observed mortality rates were lower among patients treated with pimavanserin compared with those treated with other atypical antipsychotics.

STUDY REGISTRATION

European Union Post-authorization Study (EU PAS) register number 46331.

Role of Pimavanserin Treatment-Continuity on Discharge From Long-term Care: Assessing the Quality of Antipsychotic Medication Review

Objective: To investigate the role of (1) antipsychotic medication review (AP-MR) documentation quality of Minimum Data Set 3.0 (MDS) surveys, and (2) treatment-continuity on discharge-to-community and clinical outcomes among long-term care (LTC) residents treated with pimavanserin. Design, Setting, and Participants: A retrospective cohort analysis of Parts A, B, and D claims from Medicare 100% sample merged with MDS data from June 2016 through December 2018 was conducted. Residents with more than 100-day LTC stay and 1 pimavanserin prescription or more with completed antipsychotic-use MDS question were selected. AP-MR documentation quality (ie, gradual dose reduction [GDR] attempts, clinical contraindication to GDR), discharge-to-community, and clinical outcomes (eg, falls, fractures) were obtained from MDS. Treatment-continuity was assessed from Part D claims. Data Analysis: Descriptive statistics (frequencies, proportions, Chi-square tests, and means) and adjusted logistic regressions (ORs with 95% CIs reported association between pimavanserin treatment-continuity and discharge-to-community. Results: Of 4,021 eligible residents, 29% (n = 1,182) attempted a GDR per AP-MR MDS documentation. Approximately 41% (n = 1,665) had documentation showing GDR was clinically contraindicated, yet 39% (n = 645) still attempted GDR. While overall discharge-to-community rates were low, it was significantly higher (P < 0.05) among LTC residents continuing (14.94%; n = 380/2,546) versus discontinuing (11.84%; n = 171/1,444) pimavanserin. OR for treatment-continuity was 1.96, 95% CI 1.50-2.55. Residents continuing pimavanserin had lower incidents of falls (2.8% vs 9.4%), hip fractures (0.29% vs 0.69%), and pelvic/femur fractures (0% vs 0.92%) versus those residents who discontinued it. Conclusions: Among LTC-stay residents, high discordance between GDR rates and AP-MR MDS documentation quality was observed. Pimvanserin treatment-continuity showed greater likelihood of discharge-to-community; continued documentation training can ensure appropriate antipsychotic use with a balanced benefit:risk profile.

Pimavanserin and Parkinson's Disease Psychosis: A Narrative Review

Pimavanserin (PMV) is the first approved drug for treating hallucinations and delusions in Parkinson's disease (PD) psychosis. Psychosis is one of the leading causes of nursing home placement in people with PD. Furthermore, hallucinations are a more frequent cause of institutionalization than motor disability or dementia related to PD. The management of PD psychosis involves antipsychotic medications. Most of the drugs in this class directly block dopamine D2 receptors, leading to significantly worsening motor symptoms in patients with PD. The most commonly used medications for managing PD psychosis are quetiapine, clozapine, and PMV. This literature review aims to study pimavanserin's history, mechanism, clinical trials, and post-marketing experience. PMV is a potent 5-HT2A receptor antagonist/inverse agonist. Moreover, this drug can interact with 5-HT2C receptors. We calculated some physicochemical descriptors and pharmacokinetic properties of PMV. Eight clinical trials of PMV and PD psychosis are registered on ClinicalTrials.gov. Only four of them have complete results already published. Meta-analytic results showed that PMV efficacy is inferior to clozapine. However, PMV has a significantly lower number of side-effects for managing psychosis in PD. Medicare database assessment revealed 35% lower mortality with PMV compared to other atypical antipsychotics. Moreover, sensitive statistical analysis demonstrated that PMV is a protective factor for the risk of falls in individuals with PD.

Hallucinations and delusions associated with Parkinson's disease psychosis: safety of current treatments and future directions

INTRODUCTION

: Over half of Parkinson's disease (PD) patients develop psychotic symptoms, and PD psychosis (PDP) is associated with significant distress to patients, caregiver burden, and impairs quality of life. Pharmacological therapy is limited to atypical antipsychotics.

AREAS COVERED

: This review will summarize efficacy but will focus on the safety of antipsychotics for treating PDP, and in particular the off-target safety issues including cognitive impairment, sleep disturbance, cardiovascular effects, and motor function.

EXPERT OPINION

: Pimavanserin is the only medication approved in the US for treating PDP, however clozapine is also considered efficacious. Despite lack of substantial evidence for efficacy, quetiapine is commonly used to treat PDP. Despite the effectiveness of pimavanserin and clozapine for treating PDP, a need exists for additional pharmacological agents that are effective for PDP while providing an acceptable safety and tolerability profile. Medications to treat PDP should avoid worsening motor function, and also minimize sleep disturbances, cognitive impairment, cardiovascular effects, and other non-motor safety concerns. A neutral effect or reduction in mortality risk associated with PD and PDP would be ideal, and low rate of discontinuation due to AEs is desirable. Lastly, medications that can be used safely in combination with other pharmacological agents is essential.