Fig. 1.

Kaplan-Meier graph of survival showing the survival curves of control and PD patients with low versus high WMH loads (left, median split) and low, medium, and high WMH loads (right, tertile split) demonstrating the compounded effect of PD and WMH load. A 2-point drop in MoCA was considered as the survival event and the time from baseline MoCA measurement to the visit where the 2-point drop occurred was considered as survival time. HC=Healthy Control. PD = Parkinson's Disease. MoCA = Montreal Cognitive Assessment Score.