Time to PIGD score of 2 or more
| Non-carriers | All GBA1 variants | Non-pathogenic variants | Pathogenic mutations | |
| Number | 214 | 48 | 25 | 17 |
| Estimated mean time to PIGD ≥2 (years) | 7.7 (7.2 to 8.3) | 6.8 (5.6 to 7.9) | 6.9 (5.3 to 8.5) | 5.7 (4.4 to 7.0) |
| Estimated median time to PIGD ≥2 (years) | 8.6 (7.4 to 9.9) | 6.0 (5.1 to 7.0) | 6.0 (5.1 to 7.0) | 4.9 (3.1 to 6.6) |
| 5-year survival to PIGD ≥2 (%) | 76.1 (SE 3.2) | 62.6 (SE 8.1) | 71.5 (SE 9.9) | 48.8 (SE 13.9) |
| 10-year survival to PIGD ≥2 (%) | 40.9 (SE 5.6) | 37.9 (SE 8.8) | 39.0 (SE 12.0) | 30.5 (SE 13.5) |
| Log-rank p value | – | 0.094 | 0.335 | 0.066 |
| HR | – | 1.9 (1.1 to 3.2; p=0.015) | 1.6 (0.8 to 3.1; p=0.178) | 2.8 (1.4 to 5.7; p=0.005) |
Long-term follow-up data for progression to postural instability in PD patients without GBA1 variants compared with those carrying any GBA1 variant, a pathogenic GBA1 mutation or a GBA1 ‘non-pathogenic’ variant.
HR determined by Cox regression analysis controlling for age at diagnosis, sex, baseline HY score, baseline UPDRS motor score and baseline PIGD score. Ninety-five per cent CI for HR and estimated mean and median shown in brackets. Log-rank p values shown for comparison between the GBA1 groups and the non-carrier group. Statistically significant results highlighted in bold.
HY3, Hoehn and Yahr stage three; PIGD, postural instability and gait difficulty score; UPDRS, Unified Parkinson’s Disease Rating Scale.