Longitudinal Patterns of Loss of Independence in Parkinson Disease

OBJECTIVES:

Parkinson disease (PD) symptoms progress over time, resulting in cumulative disability and loss of independence (LOI). However, it is unclear how LOI evolves in PD. An innovative use of visualization software can improve transparency by providing longitudinal views of event sequences. The study objective is to characterize the temporal sequences and patterns of LOI in PD.

METHODS:

This longitudinal study utilized data from a prospective naturalistic cohort study of PD patients seeking care at a tertiary neurologic center. Eligible patients were newly diagnosed with PD and received care from a movement disorders specialist during visits between 2003-2020. LOI was defined as needing help with activities of daily living (ADLs) based on patient-reported data collected by the modified Older Americans Resource and Services Daily Function Questionnaire at baseline and follow-up. EventFlow data visualization software was used to reveal longitudinal patterns of LOI in basic ADLs (BADLs) and instrumental ADLs (IADLs) and summarized descriptively.

RESULTS:

The sample comprised 296 PD patients (mean age 58 years, 61% male, 81% White, 94% Hoehn & Yahr stages 1 and 2, 91% without help on any ADL at baseline). Mean duration between two subsequent visits was 14.1 months (range: 1.6 to 103.5). LOI on ≥1 ADL and on ≥3 ADLs were identified in 133 and 95 patients, respectively. The most frequent first ADL requiring help was housework in 58 of 133 patients at a mean time of 4.6 years following the first visit. LOI on ≥3 IADLs was reported sooner than LOI on ≥3 BADLs in 51 of 95 patients. Longitudinal patterns of loss were revealed, including transient and persistent loss.

CONCLUSIONS:

Independence in daily function fluctuates with patterns of both transient and persistent LOI in PD. Visualized longitudinal patterns reveal the natural history of LOI in PD and can provide guidance when counseling patients.