The economic burden of Parkinson disease among Medicare beneficiaries.

The progressive nature of Parkinson disease (PD), together with a lack of curative treatments, contributes to its economic burden. To estimate the longitudinal incremental costs attributable to PD among Medicare beneficiaries. In this retrospective cohort study, we used data from the Chronic Conditions Data Warehouse to identify Medicare beneficiaries with and without PD-related claims identified from 2006 to 2014 with follow-up until 2015. We grouped PD cases and controls based on their survival profiles using a grouping algorithm that used the following baseline measures: age, race, sex, and comorbidity. We identified 3 survival groups and used them to stratify the descriptive annual cost estimates in the 9 years after the index date. We estimated the incremental 1-, 3-, and 5-year costs of PD using generalized linear models (GLM) that controlled for baseline factors. We identified 27,394 cases and controls who were grouped into 3 survival groups. The mean age of the full study sample was 73 years. No material differences were found in the incremental cost of PD across the survival groups. Based on the multivariable GLM, the 1-year incremental cost of PD was $9,625 (95% CI, $9,054-$10,197). The 3-year incremental cost of PD was $20,832 (95% CI, $19,390-$22,274). The 5-year incremental cost of PD was $27,466 (95% CI, 25,088-$29,844). Among Medicare beneficiaries, PD is associated with excess costs compared with controls. We did not identify substantial differences in the incremental cost of PD across the survival groups. This study was funded by Pfizer Inc. The funding agreement did not impact the authors' independence in designing the study, collecting the data, interpreting the data, writing the manuscript, and submitting the manuscript for publication. Dr Onukwugha reports grants from Pfizer Inc for the conduct of this study and is an employee of University of Maryland, Baltimore, which received financial support from Pfizer Inc in connection with the development of this manuscript; Dr Shulman reports research funding from Pfizer Inc related to the current work, is an employee of University of Maryland, Baltimore, which received financial support from Pfizer Inc in connection with the development of this manuscript, and reports research funding from the NIH, The Rosalyn Newman Foundation, and the Eugenia and Michael Brin family unrelated to the current work and royalties from Oxford University Press and Johns Hopkins University Press; Ms Myers and Dr Alvir are employees and stockholders of Pfizer Inc; Dr Gray was an employee and stockholder of Pfizer Inc at the time of analysis.