Abstract
BACKGROUND: Understanding how meaningful symptoms and impacts of Parkinson's change with time is necessary to select endpoints for clinical trials and to support clinical practice. OBJECTIVE: This study aimed to longitudinally evaluate the prevalence, bothersomeness, and functional impacts of early Parkinson's symptoms on daily life over a three-year study duration. METHODS: 32 participants with early Parkinson's completed qualitative interviews to map symptoms and impacts of disease annually for three years. Symptom maps were content coded for frequency and bothersomeness of symptoms and presence of related impacts. Non-parametric generalized linear mixed models (GLMM) were used to evaluate change over time. RESULTS: The most bothersome motor symptoms were tremor, gait difficulties, balance, fine motor, slow movements, and stiffness at all years. Top non-motor symptoms were fatigue, sleep, mood changes, difficulty thinking, and quiet voice. Of these, only gait and balance changed significantly over the study duration. By contrast, many functional impacts changed significantly, with all reporting increased work of living and greater effort to do usual activities by year 3. At the same time, participants reported increased ability to cope and compensate by making positive life changes which mitigated the bothersomeness of symptoms. CONCLUSIONS: Other than gait and balance, few Parkinson's symptoms increased significantly in bothersomeness over three years. However, functional and psychosocial impacts of symptoms, often attributed to more than one cause, were more sensitive to change over time.