Evolution of prodromal parkinsonian features in a cohort ofGBAmutation-positive individuals: a 6-year longitudinal study

OBJECTIVES: mutation-positive individuals over a 6-year follow-up. METHODS: group) and 30 controls (HC) at baseline and followed them for 6 years. We assessed baseline motor and non-motor signs of PD in all subjects using clinical questionnaires and scales (reduced Unified Multiple System Atrophy Rating Scale (UMSARS), Montreal Cognitive assessment (MoCA), University of Pennsylvania Smell Identification Test (UPSIT), REM Sleep Behavior Disorder screening questionnaire (RBDsq), Movement Disorders Society Unified Parkinson's Disease Rating Scale motor subscale (MDS-UPDRS III) and Beck Depression Inventory (BDI). We repeated these at the 6-year follow-up alongside venous blood sampling for measurement of glucocerebrosidase enzymatic activity (GCase). We explored whether the GCase activity level was altered in leucocytes of these subjects and how it was related to development of PD. RESULTS: and GD), an UPSIT score of 23 at baseline was correlated with worse outcome at 6 years in UPSIT, MoCA, MDS-UPDRS III and BDI. CONCLUSION: mutation-positive subjects showed a worsening in motor and non-motor prodromal PD features.