Parkinson's disease beyond 20 years

Abstract

Background: A very limited number of studies report data on the clinical features of Parkinson's disease (PD) 20 years after onset and beyond.

Objective: To characterise PD 20 years after onset, investigating the impact of age at onset and disease duration on the clinical picture and the predictors of outcomes in patients reaching the 20-year time point.

Methods: We conducted a retrospective, cross-sectional study and a longitudinal study. All case visits of patients with a disease duration ≥20 years (N=401) were stratified by disease duration (20-22, 23-25, ≥26 years) and by age at onset (cut-off, 50 years). Patients with a disease duration of 20-22 years (N=320) were prospectively followed up for a median of 45 months (IQR 23-89) for the new occurrence of fracture, percutaneous endoscopic gastrostomy, institutionalisation, confinement to a wheelchair or bed and death.

Results: Older age at onset and longer disease duration were independently associated with a higher prevalence of major motor and non-motor milestones of disease disability (no interaction observed). In the longitudinal study, the most frequent outcomes were death (N=92), confinement to a wheelchair or bed (N=67) and fracture (N=52). Mortality was associated with the gender: male, older age, dysphagia, orthostatic hypotension, postural instability, fractures and institutionalisation. Fracture was associated with postural instability. Predictors of permanent confinement to a wheelchair or bed were older age, postural instability and institutionalisation. Comorbid dementia at the 20-year examination did not predict any of the outcomes.

Conclusions: Age at onset and disease duration are independent determinants of the clinical features of PD beyond 20 years. Non-motor symptoms depend more on age at onset rather than the disease duration itself. Non-levodopa-responsive axial symptoms are the main predictors of all relevant outcomes.

Keywords: PARKINSON'S DISEASE.