Distinct Longitudinal Clinical-Neuroanatomical Trajectories in Parkinson's Disease Clinical Subtypes: Insight toward Precision Medicine.

BACKGROUND

Parkinson's disease (PD) varies widely across individuals in clinical manifestations and course of progression. Identification of distinct biological subtypes could explain this heterogeneity, identify its pathophysiology, and predict disease progression.

OBJECTIVES

Our aim was to compare longitudinal clinical trajectories and brain atrophy patterns between clinical subtypes defined at the baseline de novo PD.

METHODS

We analyzed data from 421 PD patients (mean follow-up: 8.2 years) in the Parkinson's Progression Markers Initiative (PPMI). Using multi-domain motor and non-motor criteria, de novo patients were classified into "mild motor-predominant" (n = 223), "intermediate" (n = 146), and "diffuse-malignant" (n = 52) subtypes. Deformation-based morphometry was performed on T1-weighted magnetic resonance imaging (MRIs) from 128 PD patients with at least two MRIs (71 mild motor-predominant, 42 intermediate, and 15 diffuse-malignant) and 60 controls, with an average MRI follow-up duration of 3.4 ± 1.1 in the PD cohort. Mixed-effects models compared clinical progression and longitudinal pattern of regional atrophy across subtypes.

RESULTS

The diffuse-malignant subtype exhibited faster worsening of motor severity (P = 0.007), cognition (P < 0.0001), and activities of daily living (P < 0.0001) compared to mild motor-predominant subtype over 8 years. These findings remained statistically significant after an age-matched subgroup analysis and adjustment for the levodopa treatment. Accelerated atrophy was observed in the precuneus, temporal and fusiform gyri, cerebellum, and other regions (corrected-P < 0.05).

CONCLUSIONS

Longitudinal analysis revealed distinct patterns of clinical progression and regional atrophy in PD subtypes, with the diffuse-malignant subtype showing more severe neurodegeneration and clinical deterioration suggesting existence of diverse pathophysiological mechanisms in PD. © 2025 The Author(s). Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.