LRRK2 and Parkinson disease: Participants with LRRK2 PD were older at baseline assessment (mean [SD] age, 68.4 [9.2] years) compared with individuals with idiopathic PD (mean [SD] age, 66.5 [10.0] years; P = .03) or GBA PD (mean [SD] age, 64.8 [9.7] years; P < .001) but not LRRK2/GBA PD (mean [SD] age, 65.7 [9.0] years; P = .18).