Participants with GBA PD had worse motor progression compared with those with idiopathic PD (estimate [SE], 0.49 [0.22] points/y; P = .03) and those with LRRK2 PD (estimate [SE] 0.77 [0.26] points/y; P = .004), and a not statistically significant difference from those with LRRK2/GBA PD (estimate [SE], 0.64 [0.36] points/y; P = .07). Here, LRRK2 is linked to Parkinson disease.