Glymphatic function as a predictor of mild cognitive impairment to dementia conversion in Parkinson’s disease

Motivation: Impaired glymphatic function is reported to be associated with cognitive function in Parkinson’s disease (PD). However, an evaluation of the role of the glymphatic dysfunction contributing to the dementia conversion of mild cognitive impairment (MCI) with use of MRI remains lacking. Goal(s): To evaluate the value of glymphatic function to predict the dementia conversion in PD with MCI. Approach: We calculated the water diffusion in the periventricular white matter using DTI-ALPS to evaluate the glymphatic function in PD with cognitive impairment during the follow-up. Results: The left DTI-ALPS is significantly lower in dementia converters, and is valuable for prediction of PD dementia conversion. Impact: The reduction of glymphatic activity, assessed by DTI-ALPS, was more severe in PD with MCI convert to dementia. Therefore, DTI-ALPS may assist in identifying PD with MCI at a high risk of dementia conversion before the onset of dementia symptoms.