Descriptive data of the studied population
| Controls | Patients | PS | |||||
| Overall | C9orf72 | GRN | Overall | C9orf72 | GRN | ||
| N | 165 | 102 | 54 | 48 | 85 | 48 | 37 |
| Gender (F/M) | 96/69 | 46/56 | 24/30 | 22/26 | 52/33 | 30/18 | 22/15 |
| Disease phenotype | – | ||||||
| FTD (N) | – | 75 | 27* | 48 | – | – | |
| ALS (N) | 6 | 6† | – | ||||
| FTD/ALS (N) | 10 | 10‡ | – | ||||
| Psychiatric (N) | 11 | 11§ | – | ||||
| Age at disease onset (years) | – | 58.0 (53.0–64.8) | 58.0 (50.3–67.0) | 58.0 (54.8–63.0) | – | – | – |
| Age at baseline sampling (years) | 56.5 (45.9–66.3) | 62.9 (58.3–69.6) | 64.4 (58.0–71.5) | 62.1 (58.5–66.2) | 41.2 (34.2–47.5) | 42.0 (34.4–47.4) | 40.9 (33.2–48.8) |
| Age at baseline, range (years) | 21.1–83.5 | 35.5–79.9 | 39.8–79.9 | 35.5–76.2 | 20.4–79.4 | 24.0–79.4 | 20.4–68.8 |
| Disease duration at sampling (years) | – | 3.5 (2.3–5.9) | 5.1 (2.9–9.0)¶ | 2.9 (2.2–3.5)¶ | – | – | – |
| pNfL at baseline (pg/mL) | 9.88 (7.42–14.36)** | 66.25 (33.74–98.86)** | 39.49 (23.89–74.42)†† | 86.21 (58.17–118.13)†† | 8.08 (6.08–10.10)** | 8.48 (6.71–11.52) | 7.70 (5.59–9.23) |
| Mean (±SD) pNfL at baseline | 12.08 (±7.57)** | 81.21 (±75.99)** | 64.52 (±63.92)†† | 99.99 (±84.40)†† | 8.79 (±4.02)** | 9.76 (±4.69)‡‡ | 7.52 (±2.44)‡‡ |
| Individuals with follow-up (N) | 65 | 44 | 29 | 15 | 66 | 43 | 23 |
| Mean (±SD) follow-up duration (years) | 2.96 (±1.16) | 2.00 (±1.21) | 1.95 (±1.26) | 2.08 (±1.13) | 2.99 (±1.30) | 2.83 (±0.65) | 3.29 (±2.01) |
| Mean ARC (%) | +3.9** | +26.7** | +24.7†† | +29.3†† | +3.2** | +3.2 | +3.3 |
Values are indicated as median and IQR, except where differently specified. There were no statistically significant differences between the groups, apart from specific occurrences, as follows.
*3/27 patients with FTD had SP course.
†2/6 patients with ALS had SP course.
‡3/10 patients with FTD/ALS had SP course.
§4/11 patients with psychiatric presentations had SP course.
¶Different disease duration at baseline between C9orf72 and GRN patients (p=0.0001).
**Higher values in patients compared with controls (p<0.0001) and PS (p<0.0001).
††Higher values in GRN patients compared with C9orf72 patients (p<0.05).
‡‡Higher values in C9orf72 PS compared with GRN PS (p<0.01).
ALS, amyotrophic lateral sclerosis; ARC, annualised rate of change; F, female; FTD, frontotemporal dementia; M, male; pNfL, plasma neurofilament light chain; PS, presymptomatic carriers; SP, slowly progressive.