Economic Burden of Parkinson's Disease: A Multinational, Real-World, Cost-of-Illness Study

BACKGROUND

Parkinson's disease is now one of the fastest-growing neurodegenerative disorders in the developed world, with an increasing prevalence and associated socioeconomic costs. Progression of the disease leads to a gradual deterioration in patients' quality of life, despite optimal treatment, and both medical and societal needs increase, often with the assistance of paid and/or unpaid caregivers.

OBJECTIVE

We aimed to quantify the incremental economic burden of Parkinson's disease by disease severity in a real-world setting across differing geographic regions.

METHODS

Demographics, clinical characteristics, health status, patient quality of life, caregiver burden, and healthcare resource utilization data were drawn from the Adelphi Parkinson's Disease Specific Program™, conducted in the USA, five European countries, and Japan.

RESULTS

A total of 563 neurologists provided data for 5299 individuals with Parkinson's disease; 61% were male, with a mean age of 64 years. Approximately 15% of individuals were deemed to have advanced disease, with significantly more comorbidities, and a poorer quality of life, than those with non-advanced disease. Overall, the mean annual healthcare resource utilization increased significantly with advancing disease, and resulted in a three-fold difference in the USA and Europe. The main drivers behind the high economic burden included hospitalizations, prescription medications, and indirect costs.

CONCLUSIONS

People with Parkinson's disease, and their caregivers, incur a higher economic burden as their disease progresses. Future interventions that can control symptoms or slow disease progression could reduce the burden on people with Parkinson's disease and their caregivers, whilst also substantially impacting societal costs.

Cost-Effectiveness of Carbidopa-Levodopa Enteral Suspension for Advanced Parkinson's Disease in the United States

BACKGROUND

Carbidopa/levodopa enteral suspension (CLES) is indicated for the treatment of advanced Parkinson's disease (aPD) with severe motor fluctuations.

OBJECTIVE

To determine the cost, quality-adjusted life years (QALY), and cost-effectiveness of CLES compared to the standard-of-care (SoC) for aPD patients in the United States (US), using real-world data.

METHODS

A published Markov model, comprising of 25 health states and a death state, (defined by a combination of the Hoehn and Yahr scale and waking time spent in OFF-time) was adapted to estimate the benefits for CLES versus oral SoC over a patient's lifetime in the US healthcare setting. Clinical inputs were based on a clinical trial and a registry study; utility inputs were sourced from the Adelphi-Disease Specific Programmes.

RESULTS

CLES compared to SoC was associated with incremental costs ($1,031,791 vs. $1,025,180) and QALY gain (4.61 vs. 3.76), resulting in an incremental cost-effectiveness ratio of $7711/QALY.

CONCLUSION

CLES is a cost-effective treatment for aPD patients with medication resistant motor fluctuations. © 2023 AbbVie, Inc and The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Impact of advanced Parkinson's disease on caregivers: an international real-world study

BACKGROUND

Caring for a partner or family member with Parkinson's disease (PD) negatively affects the caregiver's own physical and emotional well-being, especially those caring for people with advanced PD (APD). This study was designed to examine the impact of APD on caregiver perceived burden, quality of life (QoL), and health status.

METHODS

Dyads of people with PD and their primary caregivers were identified from the Adelphi Parkinson's Disease Specific Program (DSP™) using real-world data from the United States, Japan and five European countries. Questionnaires were used to capture measures of clinical burden (people with PD) and caregiver burden (caregivers).

RESULTS

Data from 721 patient-caregiver dyads in seven countries were captured. Caregivers had a mean age 62.6 years, 71.6% were female, and 70.4% were a spouse. Caregivers for people with APD had a greater perceived burden, were more likely to take medication and had lower caregiver treatment satisfaction than those caring for people with early or intermediate PD; similar findings were observed for caregivers of people with intermediate versus early PD. Caregivers for people with intermediate PD were also less likely to be employed than those with early PD (25.3% vs 42.4%) and spent more time caring (6.6 vs 3.2 h/day).

CONCLUSIONS

This real-world study demonstrates that caregivers of people with APD experience a greater burden than those caring for people with early PD. This highlights the importance of including caregiver-centric measures in future studies, and emphasizes the need for implementing treatments that reduce caregiver burden in APD.

TRIAL REGISTRATION

N/A.

Comparative Effectiveness of Carbidopa/Levodopa Enteral Suspension and Deep Brain Stimulation on Pill Burden Reduction in Medicare Fee-for-Service Patients with Advanced Parkinson's Disease

INTRODUCTION

Complex polypharmacy regimens to manage persistent motor fluctuations result in significant pill burden for patients with advanced Parkinson's disease (APD). This study evaluated the effectiveness of carbidopa/levodopa enteral suspension (CLES) and deep brain stimulation (DBS) on reducing pill burden in APD patients.

METHODS

We utilized 100% Medicare fee-for-service claims from 2014 to 2018 linked to CLES Patient Support Program (PSP) data. CLES initiators (CLES-I) were propensity matched 1:1 with patients enrolled in PSP who did not initiate treatment (CLES-NI) (N = 188) or undergo DBS, and 1:3 with patients who received DBS (N = 204, N = 612). Average daily pill burden and levodopa equivalent daily dosage (LEDD) were measured at baseline, 0-6 months and 7-12 months follow-up.

RESULTS

CLES-I and CLES-NI had higher pill burden than DBS patients at baseline. However, at 6 months post-treatment, CLES-I had significantly fewer pills/day than CLES-NI (4.7 versus 11.4, p < 0.05) and DBS (4.8 versus 7.4, p < 0.05). A significant reduction in pill burden was observed at 0-6 months (46.3%) and 7-12 months (68.3%) follow-up for CLES-I (p < 0.001) versus increased burden for CLES-NI (+10.5%, p < 0.05 and +8.2%, p > 0.05) and insignificant reductions for DBS (-3.9% and -6.1%, p > 0.05). Mean adjusted pill burden showed 57.3% fewer pills at 0-6 months and 74.1% at 7-12 months among CLES-I compared with CLES-NI, and 49.6% and 70.1% reduction compared with DBS. CLES-I showed a decrease in LEDD at 7-12 months compared with baseline (935 to 237 mg) and to CLES-NI (237 mg versus 1112 mg) and DBS patients (236 mg versus 594 mg).

CONCLUSION

CLES led to a significant reduction in pill burden and oral LEDD compared with CLES-NI and DBS patients. Pill burden reduction could be considered a treatment goal for patients with APD challenged by complex polypharmacy regimens that interfere with activities of daily living and quality of life.

The Cost Effectiveness of Levodopa-Carbidopa Intestinal Gel in the Treatment of Advanced Parkinson's Disease in England

BACKGROUND

Parkinson's disease is a progressive neurodegenerative disease, which significantly impacts patients' quality of life and is associated with high treatment and direct healthcare costs. In England, levodopa/carbidopa intestinal gel (LCIG) is indicated for the treatment of levodopa-responsive advanced Parkinson's disease with troublesome motor fluctuations when available combinations of medicinal products are unsatisfactory.

OBJECTIVE

We aimed to determine the cost effectiveness of LCIG compared to the standard of care for patients with advanced Parkinson's disease in England, using real-world data.

METHODS

A Markov model was adapted from previous published studies, using the perspective of the English National Health System and Personal and Social Services to evaluate the cost effectiveness of LCIG compared to standard of care in patients with advanced Parkinson's disease over a 20-year time horizon. The model comprised 25 health states, defined by a combination of the Hoehn and Yahr scale, and waking time spent in OFF-time. The base case considered an initial cohort of patients with an Hoehn and Yahr score of ≥ 3, and > 4 h OFF-time. Standard of care comprised standard oral therapies, and a proportion of patients were assumed to be treated with subcutaneous apomorphine infusion or injection in addition to oral therapies. Efficacy inputs were based on LCIG clinical trials where possible. Resource use and utility values were based on results of a large-scale observational study, and costs were derived from the latest published UK data, valued at 2017 prices. The EuroQol five-dimensions-3-level (EQ-5D-3L) instrument was used to measure utilities. Costs and quality-adjusted life-years were discounted at 3.5%. Both deterministic and probabilistic sensitivity analyses were conducted.

RESULTS

Total costs and quality-adjusted life-years gained for LCIG vs standard of care were £586,832 vs £554,022, and 2.82 vs 1.43, respectively. The incremental cost-effectiveness ratio for LCIG compared to standard of care was £23,649/quality-adjusted life-year. Results were sensitive to the healthcare resource utilisation based on real-world data, and long-term efficacy of LCIG.

CONCLUSIONS

The base-case incremental cost-effectiveness ratio was estimated to be within the acceptable thresholds for cost effectiveness considered for England.

Comparative Effectiveness of Carbidopa-Levodopa Enteral Suspension and Deep Brain Stimulation on Parkinson's Disease-Related Pill Burden Reduction in Advanced Parkinson's Disease: A Retrospective Real-World Cohort Study

Introduction

In advanced Parkinson’s disease (PD), a high pill burden is associated with poor compliance, reduced control of symptoms, and decreased quality of life. We assessed the impact of carbidopa–levodopa enteral suspension (CLES) and deep brain stimulation (DBS) on PD-related pill burden.

Methods

A retrospective cohort analysis was conducted in the IBM MarketScan and Medicare Supplemental databases. Patients with advanced PD, taking only PD medications, and initiating CLES or DBS between 9 January 2015 and 31 July 2019 were identified. CLES patients were matched to DBS patients in a 1:3 ratio based on a propensity score to balance patient characteristics. Pill burden was measured as a 30-day average number of PD-related pills per day and was captured monthly. Pill-free status was evaluated as the percentage of patients receiving CLES or DBS monotherapy. Descriptive statistics were used to compare pill counts and assess the proportion of patients on monotherapy at 6 and 12 months after initiating CLES or DBS.

Results

The cohorts included 34 CLES patients matched to 97 DBS patients. A significant reduction in PD-related pill burden was observed at 6 months after initiation of CLES or DBS (∆CLES: −5.62, p < 0.0001; ∆DBS: −1.48, p = 0.0022). PD-related pill burden reduction in CLES patients was significantly greater than in matched DBS patients at 6 months (∆: −4.14, p < 0.0001), which was sustained at 12 months after initiation. At 12 months, nearly three times more CLES patients were pill free than DBS patients (29.41% and 10.31%, respectively, p = 0.0123).

Conclusions

Device-aided therapies such as CLES and DBS are effective in significantly reducing PD-related pill burden. Patients treated with CLES were more likely to achieve pill-free status than patients receiving DBS.

Patterns of Daily Motor-Symptom Control with Carbidopa/Levodopa Enteral Suspension Versus Oral Carbidopa/Levodopa Therapy in Advanced Parkinson's Disease: Clinical Trial Post Hoc Analyses

Introduction

A clinical trial in advanced Parkinson’s disease (APD) has established the superiority of carbidopa/levodopa enteral suspension (CLES) in reducing total patient “off” time (OFF) and increasing total “on” time without troublesome dyskinesia (ON-woTD) over orally administered immediate-release carbidopa/levodopa tablets (IR–CL). However, temporal patterns of these improvements throughout the waking day have not been examined. In this analysis, time to ON-woTD after waking and patterns of motor-symptom control throughout the waking day were compared between CLES and IR–CL.

Methods

Post hoc analyses of APD patient-diary data from the phase 3 randomized controlled trial were used to compare changes in time to ON-woTD after waking, motor-symptom control throughout the waking day, occurrence of extreme fluctuations between OFF and “on” with troublesome dyskinesia, and motor-state transitions with CLES versus IR–CL from baseline to week 12.

Results

The sample included 33 CLES-treated and 30 IR–CL-treated patients. Among the CLES group, the percentage of patient days achieving ON-woTD within 30 min of waking was three times higher at week 12 versus baseline (33% vs. 11%, p = 0.0043); no significant change occurred with IR–CL. When the waking day was divided into four 4-h periods, CLES versus IR–CL treatment produced significantly greater reductions in OFF during three periods, and two periods had increased ON-woTD. Fewer CLES-treated patients had extreme fluctuations at week 12 (3% vs. 23%, p = 0.0224) compared to IR–CL-treated patients. From baseline to week 12, CLES-treated patients had greater reductions in the average number of motor-state transitions compared to IR–CL-treated patients (− 1.6, p = 0.0295).

Conclusion

CLES-treated patients experienced a more rapid onset of ON-woTD after waking and greater consistency of ON-woTD throughout their waking day than IR–CL-treated patients.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40120-022-00332-0.

In advanced Parkinson’s disease, patients’ motor-symptom states (such as “on” time without troublesome dyskinesia [good “on” time] and “off” time), and the timing at which they occur, can impact patients’ quality of life and ability to complete activities of daily living. Carbidopa/levodopa enteral suspension is administered continuously into the jejunum, potentially reducing some of the motor-state variation that is common with orally administered carbidopa/levodopa, including delayed “on” time after waking and transitions between “off” and “on” throughout the day. In post hoc analyses of clinical trial data, patterns of motor-states across the waking day were compared between carbidopa/levodopa enteral suspension and orally administered immediate-release carbidopa/levodopa at week 12. Outcomes included time to good “on” after waking; occurrence of extreme fluctuations between “off” time and “on” time with troublesome dyskinesia; time in each motor-state during 4-h intervals across the day; and frequency of motor-state transitions. Three times as many carbidopa/levodopa enteral suspension-treated patients achieved good “on” within 30 min of waking after 12 weeks versus baseline, whereas no significant change was observed for the orally administered immediate-release carbidopa/levodopa group. Compared to orally administered immediate-release carbidopa/levodopa-treated patients, fewer carbidopa/levodopa enteral suspension-treated patients experienced extreme fluctuations, had greater reductions in motor-state transitions, and greater reductions in duration of “off” during three of the four intervals in the day. These findings provide a first look at the impact of carbidopa/levodopa enteral suspension on motor-state patterns throughout the day, and suggest that carbidopa/levodopa enteral suspension provides more consistent motor-symptom control and predictable benefit throughout the day than orally administered carbidopa/levodopa.

Seek COVER: using a disease proxy to rapidly develop and validate a personalized risk calculator for COVID-19 outcomes in an international network

Background

We investigated whether we could use influenza data to develop prediction models for COVID-19 to increase the speed at which prediction models can reliably be developed and validated early in a pandemic. We developed COVID-19 Estimated Risk (COVER) scores that quantify a patient’s risk of hospital admission with pneumonia (COVER-H), hospitalization with pneumonia requiring intensive services or death (COVER-I), or fatality (COVER-F) in the 30-days following COVID-19 diagnosis using historical data from patients with influenza or flu-like symptoms and tested this in COVID-19 patients.

Methods

We analyzed a federated network of electronic medical records and administrative claims data from 14 data sources and 6 countries containing data collected on or before 4/27/2020. We used a 2-step process to develop 3 scores using historical data from patients with influenza or flu-like symptoms any time prior to 2020. The first step was to create a data-driven model using LASSO regularized logistic regression, the covariates of which were used to develop aggregate covariates for the second step where the COVER scores were developed using a smaller set of features. These 3 COVER scores were then externally validated on patients with 1) influenza or flu-like symptoms and 2) confirmed or suspected COVID-19 diagnosis across 5 databases from South Korea, Spain, and the United States. Outcomes included i) hospitalization with pneumonia, ii) hospitalization with pneumonia requiring intensive services or death, and iii) death in the 30 days after index date.

Results

Overall, 44,507 COVID-19 patients were included for model validation. We identified 7 predictors (history of cancer, chronic obstructive pulmonary disease, diabetes, heart disease, hypertension, hyperlipidemia, kidney disease) which combined with age and sex discriminated which patients would experience any of our three outcomes. The models achieved good performance in influenza and COVID-19 cohorts. For COVID-19 the AUC ranges were, COVER-H: 0.69–0.81, COVER-I: 0.73–0.91, and COVER-F: 0.72–0.90. Calibration varied across the validations with some of the COVID-19 validations being less well calibrated than the influenza validations.

Conclusions

This research demonstrated the utility of using a proxy disease to develop a prediction model. The 3 COVER models with 9-predictors that were developed using influenza data perform well for COVID-19 patients for predicting hospitalization, intensive services, and fatality. The scores showed good discriminatory performance which transferred well to the COVID-19 population. There was some miscalibration in the COVID-19 validations, which is potentially due to the difference in symptom severity between the two diseases. A possible solution for this is to recalibrate the models in each location before use.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12874-022-01505-z.

Does the 5-2-1 criteria identify patients with advanced Parkinson's disease? Real-world screening accuracy and burden of 5-2-1-positive patients in 7 countries

BACKGROUND

The burden of Parkinson's disease (PD) worsens with disease progression. However, the lack of objective and uniform disease classification challenges our understanding of the incremental burden in patients with advanced Parkinson's disease (APD) and suboptimal medication control. The 5-2-1 criteria was proposed by clinical consensus to identify patients with advancing PD. Our objective was to evaluate the screening accuracy and incremental clinical burden, healthcare resource utilization (HCRU), and humanistic burden in PD patients meeting the 5-2-1 screening criteria.

METHODS

Data were drawn from the Adelphi Parkinson's Disease Specific Program (DSP™), a multi-country point-in-time survey (2017-2020). People with PD who were naive to device-aided therapy and on oral PD therapy were included. Patients meeting the 5-2-1 screening criteria had one or more of the three clinical indicators of APD: (i) ≥5 doses of oral levodopa/day, OR (ii) "off" symptoms for ≥2 h of waking day, OR (iii) ≥1 h of troublesome dyskinesia. Clinician assessment of PD stage was used as the reference in this study. Clinical screening accuracy of the 5-2-1 criteria was assessed using area under the curve and multivariable logistic regression models. Incremental clinical, HCRU, and humanistic burden were assessed by known-group comparisons between 5 and 2-1-positive and negative patients.

RESULTS

From the analytic sample (n = 4714), 33% of patients met the 5-2-1 screening criteria. Among physician-classified APD patients, 78.6% were 5-2-1 positive. Concordance between clinician judgment and 5-2-1 screening criteria was > 75%. 5-2-1-positive patients were nearly 7-times more likely to be classified as APD by physician judgment. Compared with the 5-2-1-negative group, 5-2-1-positive patients had significantly higher clinical, HCRU, and humanistic burden across all measures. In particular, 5-2-1-positive patients had 3.8-times more falls, 3.6-times higher annual hospitalization rate, and 3.4-times greater dissatisfaction with PD treatment. 5-2-1-positive patients also had significantly lower quality of life and worse caregiver burden.

CONCLUSIONS

5-2-1 criteria demonstrated potential as a screening tool for identifying people with APD with considerable clinical, humanistic, and HCRU burden. The 5-2-1 screening criteria is an objective and reliable tool that may aid the timely identification and treatment optimization of patients inadequately controlled on oral PD medications.

Psychometric Properties of Clinical Indicators for Identification and Management of Advanced Parkinson's Disease: Real-World Evidence From G7 Countries

Introduction

Standardized and validated criteria to define advanced Parkinson’s disease (PD) or identify patient eligibility for device-aided therapy are needed. This study assessed the psychometric properties of clinical indicators of advanced PD and eligibility for device-aided therapy in a large population.

Methods

This retrospective analysis of the Adelphi Parkinson’s Disease Specific Programme collected data from device-aided therapy-naïve people with PD in G7 countries. We assessed the presence of 15 clinical indicators of advancing PD and seven indicators of eligibility for device-aided therapy in patients classified with advanced PD or as eligible for device-aided therapy by the treating physician. Accuracy was assessed using area under the curve (AUC) and multivariable logistic regression models. Construct validity was examined via known-group comparisons of disease severity and burden among patients with and without each clinical indicator.

Results

Of 4714 PD patients, 14.9% were classified with advanced PD and 17.5% as eligible for device-aided therapy by physician judgment. The presence of each clinical indicator was 1.9- to 7.3-fold more likely in patients classified with advanced PD. Similarly, the presence of device-aided therapy eligibility indicators was 1.8- to 5.5-fold more likely in patients considered eligible for device-aided therapy. All indicators demonstrated high clinical screening accuracy for identifying advanced PD (AUC range 0.84–0.89) and patients eligible for device-aided therapy (AUC range 0.73–0.80). The Unified Parkinson’s Disease Rating Scale (UPDRS) score, cognitive function, quality of life, and caregiver burden were significantly worse in indicator-positive patients.

Conclusion

Specific clinical indicators of advanced PD and eligibility for device-aided therapy demonstrated excellent psychometric properties in a large sample, and thus may provide an objective and reliable approach for patient identification and treatment optimization.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40120-021-00313-9.

Advanced Parkinson’s disease (PD) refers to the stage of disease when motor complications are difficult to manage with standard therapy. Patients reaching this stage of the disease may benefit from a treatment change from pills to the so-called device-aided therapies. However, there is currently no unanimous definition of advanced PD, which makes it challenging to identify suitable candidates for device-aided therapies. There is urgent need to define specific features (or ‘clinical indicators’) to support healthcare professionals and patients in the identification of advanced PD as well as to define suitability for device-aided therapy. This study aimed to assess the accuracy of 15 clinical indicators and seven device-aided therapy eligibility criteria using information from a large database of 4714 patients in G7 countries. Physicians classified 14.9% of patients as having advanced PD and 17.5% were judged to be eligible for device-aided therapy. Each clinical indicator or device-aided therapy eligibility indicator was detected more frequently in patients classified as having advanced PD and in patients considered eligible for device-aided therapy, respectively. All indicators had high accuracy for identifying advanced PD and device-aided therapy-eligibility. These previously identified clinical indicators of advanced PD and device-aided therapy eligibility may provide an objective and reliable approach for patient screening and treatment optimization.

Comparative Effectiveness of Device-Aided Therapies on Quality of Life and Off-Time in Advanced Parkinson's Disease: A Systematic Review and Bayesian Network Meta-analysis

INTRODUCTION

Research comparing levodopa/carbidopa intestinal gel (LCIG), deep brain stimulation (DBS), and continuous subcutaneous apomorphine infusion (CSAI) for advanced Parkinson's disease (PD) is lacking. This network meta-analysis (NMA) assessed the comparative effectiveness of LCIG, DBS, CSAI and best medical therapy (BMT) in reducing off-time and improving quality of life (QoL) in patients with advanced PD.

METHODS

A systematic literature review was conducted for randomized controlled trials (RCTs), observational and interventional studies from January 2003 to September 2019. Data extracted at baseline and 6 months were off-time, as reported by diary or Unified Parkinson's Disease Rating Scale Part IV item 39, and QoL, as reported by Parkinson's Disease Questionnaire (PDQ-39/PDQ-8). Bayesian NMA was performed to estimate pooled treatment effect sizes and to rank treatments in order of effectiveness.

RESULTS

A total of 22 studies fulfilled the inclusion criteria (n = 2063 patients): four RCTs, and 16 single-armed, one 2-armed and one 3-armed prospective studies. Baseline mean age was between 55.5-70.9 years, duration of PD was 9.1-15.3 years, off-time ranged from 5.4 to 8.7 h/day in 9 studies, and PDQ scores ranged from 28.8 to 67.0 in 19 studies. Levodopa/carbidopa intestinal gel and DBS demonstrated significantly greater improvement in off-time and QoL at 6 months compared with CSAI and BMT (p < 0.05). There was no significant difference in the effects of LCIG and DBS, but DBS was ranked first for reduction in off-time, and LCIG was ranked first for improvement in QoL.

CONCLUSIONS

This NMA found that LCIG and DBS were associated with superior improvement in off-time and PD-related QoL compared with CSAI and BMT at 6 months after treatment initiation. This comparative effectiveness research may assist providers, patients, and caregivers in the selection of the optimal device-aided therapy.

Low Sustainment of High-Dose Oral Medication Regimens for Advanced Parkinson's Disease in Medicare Beneficiaries

BACKGROUND

Increasing doses of oral antiparkinson medications are indicated in advanced Parkinson's disease (PD), but little is known about sustainment of high-dose regimens.

OBJECTIVE

To investigate sustainment of high-dose oral medication regimens in Medicare beneficiaries with incident advanced PD.

METHODS

This retrospective cohort study utilized 100%fee-for-service Medicare claims from 2011-2013. We identified advanced PD using a pharmacy claims-based proxy and selected patients who initiated a new high-dose oral medication regimen (daily levodopa equivalent dose [LED] >1000 mg/day for ≥30 days) in 2012. In the following 12 months, we examined: 1) annual proportion of days covered (PDC)≥0.80 and 2) presence of a ≥ 90 day continuous gap at varying dosage thresholds: the initial >1000 mg/day, >800 mg/day, >500 mg/day, or >0 mg/day.

RESULTS

We identified 9,405 patients with advanced PD (mean age 77.4 [SD 6.8] years; 53%men). Only 5%maintained a regimen of >1000 mg/day at PDC ≥0.80; 75% had a ≥ 90-day gap in that dosage level. At a dosage threshold of >800 mg/day, 20% had a PDC ≥0.80 and 53% had a ≥ 90-day gap; at >500 mg/day, 56% had a PDC ≥0.80 and 19%had a ≥ 90-day gap; and at >0 mg/day (any dose), 76% had a PDC ≥0.80 and only 10%had a≥90-day gap.

CONCLUSION

Few patients with advanced PD sustained a high-dose oral medication regimen in the year following initiation, but most sustained a substantially lower-dose regimen. Strategies to improve advanced PD treatment are needed.

Burden of Parkinson's Disease by Severity: Health Care Costs in the U.S. Medicare Population

BACKGROUND

Current understanding of the health care costs of Parkinson's disease (PD) and the incremental burden of advanced disease is incomplete.

OBJECTIVES

The aim of this study was to assess the direct economic burden associated with advanced versus mild/moderate PD in a prevalent national sample of elderly U.S. Medicare beneficiaries with a PD diagnosis.

METHODS

Analyzing 100% fee-for-service Medicare claims from 2013, we defined advanced PD with a medication-based algorithm and calculated all-cause and PD-related costs for the overall sample and by disease severity. We measured primary PD-related costs (based on claims with a primary diagnosis of PD) and any PD-related costs (based on claims with PD in any diagnostic field). Generalized linear models were used to estimate risk-adjusted mean cost differences between the advanced and mild/moderate PD groups for the calendar year.

RESULTS

The final sample (N = 144,703) had mean observed all-cause, primary PD-related, and any PD-related costs of $23,041 (SD, $34,045), $3429 (SD, $7431), and $9924 (SD, $22,140), respectively. Twenty percent of patients were classified as advanced PD. Costs varied substantially; any PD-related mean costs were $483 for the lowest patient decile (which included 1% of the advanced group) and $48,145 for the highest decile (which included 15% of the advanced group). Incremental risk-adjusted costs of advanced PD were $5818 (95% confidence interval [CI]: $5411-$6225) for all-cause costs, $3644 (95% CI: $3484-$3806) for primary PD-related costs, and $6088 (95% CI: $5779-$6398) for any PD-related costs.

CONCLUSIONS

Elderly Medicare beneficiaries with PD had substantial variation in PD-related costs. Advanced PD was associated with a larger economic burden than mild/moderate PD. © 2020 International Parkinson and Movement Disorder Society.

Use of a medication-based algorithm to identify advanced Parkinson's disease in administrative claims data: Associations with claims-based indicators of disease severity

Introduction

Lack of a gold standard definition for advanced Parkinson's Disease (APD), coupled with absence of disease severity information in diagnostic codes, hinders use of large administrative databases for conducting population health and comparative effectiveness studies.

Methods

Using pharmacy claims data, we created an algorithm to identify APD: any 30-day average levodopa equivalent dose (LED) >1000 mg/day. Using 2013 100% U.S. Medicare claims, we applied this algorithm and used multivariate logistic regression to examine associations between assigned APD status and claims-based indicators of PD severity (any deep brain stimulation, fall, hallucinations, walker, wheelchair, specialty bed, dementia diagnosis, skilled nursing facility, hospice), adjusting for sociodemographic, clinical, and treatment characteristics. Levodopa >1000 mg/day, levodopa >800 mg/day and LED >800 mg/day were used in sensitivity analysis.

Results

In our sample (N = 144,703), 20% were assigned APD status based on the LED >1000 mg/day cut-off. This group had significantly higher odds of having each claims-based indicator, compared with those assigned mild-moderate PD status. Odds ratios were highest for indicators for any DBS (OR: 2.96; 95% CI:2.75–3.19) and specialty bed (OR:2.15, 95% CI: 1.99–2.32) and lowest for fall (OR:1.27; 95% CI:1.20–1.34) and dementia diagnosis (OR:1.21; 95% CI:1.18–1.25). Results based on alternative approaches were similar.

Conclusions

Medicare patients classified as having APD via a pharmacy claims-based algorithm had higher odds of having claims-based clinical markers of APD, compared with patients categorized as having mild-moderate PD. This proxy strategy could facilitate future claims-based studies and warrants further refinement and validation using medical records or other clinical sources.

•

Prescription claims can be used to calculate average daily levodopa-equivalent dose.

•

An algorithm (LED >1000 mg/day) was used to identify advanced Parkinson's in claims.

•

20% of people with Parkinson's disease in a Medicare sample aged 65+ met this definition.

•

The remaining 80% of the sample was classified as having mild/moderate disease.

•

The advanced group had higher odds of having clinical markers of advanced disease.