FIGURE 7.

Relation of baseline reference structures on MoCA total and subscore trajectory. In Parkinson’s disease (PD) patients, expected total Montreal cognitive assessment (MoCA) trajectory based on (A) baseline thalamic volume and (B) corticospinal tract (CST) fractional anisotropy (FA). Expected attention/executive (att/exec) subscore trajectory based on (C) baseline thalamic volume and (D) CST FA. Expected memory subscore trajectory based on (E) baseline thalamic volume and (F) CST FA. The bold lines represent the expected trajectory for a 65-year-old woman at 4 years disease duration with a baseline metric 1 standard deviation (SD) above the sample mean (green) and 1 SD below the sample mean (red). The low/high value is 6683/7742 mm³ for thalamic volume and 0.36/0.38 for CST FA. The cognitive metric (total MoCA or MoCA subscore, y-axis) was the outcome variable. Shading represents the standard error of the mean of the outcome variable. Baseline age, baseline disease duration, sex, baseline MRI metric, study time, and the study time × baseline MRI interaction term were the fixed effects. Intercept and slope were the random effects for each PD participant. p_ia represents effect of baseline metric on slope of cognitive metric. Attention/executive subscore is the sum of trails, clock, digits, vigilance, and serial 7s, and memory subscore is the sum of delayed recall and orientation.