Table 1.
Demographic and clinical characteristics
| ALS | Controls | |
| n | 192 | 314 |
| Sex=female | 78 (40.6) | 95 (30.3) |
| Age at first MRI, years | 62.4 (53.7–68.4) | 62.5 (54.7–68.5) |
| Age at onset, years | 60.5 (52.6–66.0) | |
| Handedness=right | 150 (78.1) | 241 (76.8) |
| Visit interval, m | 4.4 (3.6–5.5) | 14.0 (10.8–17.7) |
| Site of disease onset | ||
| Bulbar region | 49 (25.5) | |
| Arms, right/left/both | 78 (40.6), 30/29/19 | |
| Legs, right/left/both | 65 (33.9), 28/26/11 | |
| Diagnostic delay, m | 9.8 (5.8–18.0) | |
| Diagnosis to study interval, m | 4.0 (2.3–6.2) | |
| Disease duration, m | 14.4 (10.0–23.4) | |
| C9orf72 repeat length expansion | 16 (8.8) | |
| FVC at diagnosis, % of predicted | 101.0 (90.8–111.3) | |
| King’s stage at visit 1, 1/2/3/4/missing | 71/54/42/0/25 | |
| MiToS stage at visit 1, 0/1/2/3/4/missing | 163/4/1/0/0/24 | |
| ECAS total score | 113 (102–119) | 114 (106–119) |
| ECAS, ALS-specific score | 85 (76–89) | 85 (78–88) |
| ECAS, ALS-non-specific score | 30 (26–32) | 30 (28–31) |
| bvFTD at visit 1 | 9 (4.7) | |
| ALSFRS-R score at visit 1 | 41 (38–44) | |
| Progression rate at visit 1 | 0.4 (0.2–0.6) | |
| Progression rate between visits 1 and 2 | 0.6 (0.3–1.1) |
Data are count (%) or median (25th quantile–75th quantile). Progression rate at visit 1 is defined as the decline in total ALSFRS-R-score per month from symptom onset until first visit. Progression rate between visits 1 and 2 is defined as the decline in total ALSFRS-R-score per month between visits. Presence of bvFTD is based on the Rascovsky criteria for behavioural FTD.20 All patients had two follow-up visits; for controls this was not obligatory; 145 controls completed the second visit.
ALS, amyotrophic lateral sclerosis; ALSFRS-R, Revised ALS Functional Rating Scale; bvFTD, behavioural frontal temporal dementia; ECAS, Edinburgh Cognitive and Behavioural ALS Screen; FVC, forced vital capacity; King's, King’s clinical staging system; MiToS, stage in Milano-Torino functional staging system.