Description of progression of clinical features after 6 years of follow-up in the three groups of subjects
| HC | Het GBA | GD | |
| Cognitive impairment (MoCA <26) | 2 (12.5%) | 1 (6.3%) | 5 (16.1%) |
| Hyposmia (UPSIT cut-off ≤23) | 1 (6.3%) | 3 (19%) | 4 (12.9%) |
| Depression (BDI cut-off ≥10) | – | 1 (6.3%) | 8 (25.8%) |
| RBDs (RBDsq ≥5) | 1 (8.3%) | 2 (13.3%) | 4 (18.2%) |
| Global bradykinesia (MDS-UPDRS part III subscore ≥1) | – | – | 4 (12.9%) |
| Resting tremor (MDS-UPDRS part III subscore ≥1) | – | – | 2 (6.5%) |
| Abnormal posture (MDS-UPDRS part III subscore ≥1) | 3 (18.9%) | 3 (19%) | 8 (25.8%) |
| Postural instability (MDS-UPDRS part III subscore ≥1) | 1 (6.3%) | 4 (25%) | 6 (19.4%) |
| Action tremor (MDS-UPDRS part III subscore ≥1) | 2 (12.5%) | 1 (6.3%) | 10 (32.3%) |
| Postural tremor (MDS-UPDRS part III subscore ≥1) | 3 (18.9%) | 1 (6.3%) | 4 (12.9%) |
| Clinically defined PD | – | – | 1 (3.2%) |
Data are presented as number of cases and percentage of all subjects within group. Cut-off references are reported in the Materials and methods section.
BDI, Beck Depression Inventory; Het GBA, heterozygous GBA1 mutation carriers; MDS-UPRS, Movement Disorders Society Unified Parkinson’s Disease Rating Scale; PD, Parkinson disease; RBD, REM sleep behaviour disorder; UPSIT, University of Pennsylvania Smell Identification Test.