Objective: To carry out a survey on a representative sample of people with Parkinson’s (PwP) about their lived experience of a comprehensive list of Parkinson disease (PD) symptoms, their perceived relevance of each of them, and the severity thresholds which would, in their view, constitute disease progression. To embed this information in the design of novel clinical outcome assessments (COAs) for disease-modifying PD clinical trials.

Background: The absence of disease-modifying therapies in PD may be partly explained by the lack of COAs which can adequately capture disease progression. Patient input is key to optimising all aspects of trial design, and current regulatory advice requires that PD clinical trials include patient-relevant COAs. Currently there are no data on PwP-defined severity thresholds of disease progression, nor insights regarding the diversity of opinions from different PD subgroups.

Method: A bespoke cross-sectional survey was designed with input from PwP, including items regarding demographic information, MDS-UPDRS part I (non-motor experiences of daily living (EDL)), II (motor EDL), and IV (motor fluctuations) items, as well as social/care-related issues and a free text field to flag additional symptoms. For each item, the survey enquired about lived experience, relevance, and opinion regarding severity level that would define PD progression.

Results: Responses were collected from a representative sample of 110 PwP in terms of age (mean: 61.5 years, standard deviation (SD): 11.1 years), sex (44 females), and disease duration (mean: 10.5 years, SD: 6.4 years). Most participants reported lived experience of at least one item from most survey sections (Part I: 110/110; II: 109/110; IV: 97/110; Social/care-related: 21/110; Other: 35/110). Globally, the five most relevant symptoms were “Thinking problems” (median threshold of progression: Moderate), “Walking and balance” (Mild), “Dyskinesia” (Mild; Present ≤ 25% of awake time), “Change in living situation” (Occasional need for carers), and “Freezing of gait” (Mild). Results varied when stratifying by demographic characteristics.

Conclusion: This study provides unique evidence on PwP-informed thresholds to define PD progression. Survey responses will help refine milestone-based COAs which are congruent with PD natural history, resistant to dopaminergic treatment effect and relevant to PwP.

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MDS Abstracts - https://www.mdsabstracts.org/abstract/patient-defined-disease-progression-in-parkinson-disease-towards-patient-relevant-outcome-measures/