Fig. 2.

Box-and-whisker plots for comparisons of PBVC and ventricular enlargement for each group over 18 months. Negative % represents a decrease in volume over time. Differences between groups were assessed by using ANCOVA controlling for age, gender, education, inter-scan interval, and LEDD, with post hoc Tukey-Kramer tests. (A) Whole-brain atrophy was greater in PD-MCI compared with both PD-NC and HC (B) Only the amnestic subgroup of PD-MCI showed increased whole-brain atrophy compared with PD-NC, HC, and non-amnestic PD-MCI. (C, D) Ventricular enlargement was greater in PD-MCI compared with PD-NC and healthy controls, particularly in the amnestic subgroup of PD-MCI. Abbreviations: Amn, amnestic; HC, healthy controls; NON-amn, non-amnestic; PBVC, percentage brain volume change; PD-MCI, Parkinson's disease with mild cognitive impairment; PD-NC, Parkinson's disease with no cognitive impairment; VIENA, ventricular enlargement.