Progressive brain atrophy and clinical evolution in Parkinson's disease

Area of Science:

• Neuroscience
• Neurology
• Radiology

Background:

• Parkinson's disease (PD) exhibits heterogeneous clinical progression.
• Understanding brain structure changes is crucial for predicting PD evolution.

Purpose of the Study:

• To investigate progressive brain atrophy patterns in PD based on disease stage.
• To correlate cortical thinning and subcortical atrophy with clinical motor and non-motor symptom progression.

Main Methods:

• 154 PD patients underwent longitudinal motor, non-motor, and structural MRI over 4 years.
• Cluster analysis identified clinical subtypes; MRI assessed atrophy.
• Brain atrophy progression was compared across subtypes and correlated with clinical outcomes.

Main Results:

• Two main PD clusters emerged: mild (N=87) and moderate-to-severe (N=67).
• Mild PD further divided into motor-predominant and diffuse subtypes, with the latter showing earlier cognitive/non-motor issues.
• Mild-diffuse PD patients exhibited greater cortical and hippocampal atrophy progression; baseline atrophy predicted long-term symptom worsening.

Conclusions:

• Brain atrophy accelerates early in PD, with distinct patterns related to clinical subtypes.
• Structural MRI is a valuable tool for monitoring and predicting PD progression, including motor, cognitive, and mood deficits.