Gait Analysis of GBA Mutation Carriers with Parkinson’s Disease (P4.7-009)

Objective: To use quantitative motion analysis to measure gait asymmetry in the glucocerebrosidase (GBA) gene mutation and non-mutation carriers with Parkinson’s disease (PD) in the OFF state compared with healthy controls (HCs). Background: GBA mutation carriers with PD are at higher risk of cognitive decline, but the motor phenotype is not well defined. We hypothesized that GBA mutation carriers had more symmetric arm swing velocity, stride length, and arm swing range of motion (ROM) compared with non-mutation carriers. Design/Methods: We screened 88 PD subjects and identified 11 GBA mutation carriers. Non-mutation carriers and HCs were matched to GBA mutation carriers based on age of onset, disease duration, and sex. GBA mutation carriers and matched non-mutation carriers completed the Instrumented Stand and Walk test and neurologic exam. Asymmetry in arm swing velocity, stride length, and arm swing range of motion were calculated and compared between the 3 groups. Results: Motion analysis results were available for 16 non-mutation carriers, 11 GBA mutation carriers, and 11 HCs. No significant difference in age of onset, sex, disease duration, or H&Y stage was found comparing the 3 groups. Significant differences were found between GBA-mutation carriers (and non-mutation carriers in measures of arm swing velocity asymmetry (10.9 +/− 8.1 vs. 22.9 +/− 12.2 degrees/sec, respectively p = 0.032) and in arm ROM asymmetry for non-mutation carriers (degrees) vs. HCs (32.3 +/− 18.7 vs. 15.0 +/− 14.1 degrees, respectively, p=0.027). Conclusions: GBA mutation carriers demonstrate more symmetric arm swing velocity than non-GBA mutation carriers. GBA mutation carriers demonstrate arm swing asymmetry and arm ROM asymmetry that was comparable to that seen in healthy controls. Arm swing velocity asymmetry may be a marker of GBA status. Disclosure: Dr. Gera has nothing to disclose. Dr. O’Keefe has nothing to disclose. Dr. Ouyang has nothing to disclose. Dr. Pal has nothing to disclose.