Demographic, clinical, electrophysiological and neuroimaging baseline characteristics
| Patients (n=29) | Controls (n=22) | Difference, patients >controls (95% CI) | P value | |
| Mean age, years (SD) | 57.1 (13.5) | 54.2 (15.7) | 3.0 (−5.3 to 11.1) | 0.474 |
| Gender | 7 (24.1%) females | 9 (40.9%) females | −16.8% (−42.2% to 9.3%) | 0.207 |
| Mean weight, kg (SD) | 77.7 (15.3) | 75.0 (15.1) | 2.7 (−6.1 to 11.4) | 0.540 (0.746) |
| Median weeks from symptom onset (range) | 66 (25–265) | |||
| Mean MRC score (SD) | 100/110 (10.6) | |||
| Mean ALSFRS-R (SD) | 40/48 (4.5) | |||
| Mean MUNIX biceps (SD) | 129.3 (53.9) | 200.2 (85.8) | −71.0 (−112.6 to –29.3) | 0.001 (<0.001) |
| Mean CMAP biceps, mV (SD) | 5.5 (2.2) | 7.9 (3.4) | −2.3 (−4.0 to –0.7) | 0.007 (0.002) |
| Mean MUSIX biceps (SD) | 41.4 (9.6) | 39.6 (4.1) | 1.7 (−2.9 to 6.3) | 0.459 (0.990) |
| Mean MUNIX TA (SD) | 83.5 (48.6) | 139.3 (32.2) | −55.8 (−80.6 to –30.9) | <0.001 (<0.001) |
| Mean CMAP TA, mV (SD) | 4.2 (1.9) | 5.4 (3.7) | −1.2 (−2.1 to –0.3) | 0.002 (0.002) |
| Mean MUSIX TA (SD) | 56.4 (27.3) | 39.7 (6.4) | 16.7 (4.5 to 29.0) | 0.009 (0.016) |
| MRI relative T2 signal summary score all regions (SD) | 0.39 (0.10) | 0.30 (0.04) | 30.3% (15.0% to 45.5%) | <0.001 (<0.001) |
| MRI relative T2 signal tongue (SD) | 0.69 (0.13) | 0.64 (0.09) | 8.3% (−1.6% to 18.2%) | 0.098 (0.082) |
| MRI relative T2 signal right biceps (SD) | 0.38 (0.10) | 0.30 (0.06) | 25.2% (9.2% to 41.1%) | 0.003 (0.003) |
| MRI relative T2 signal left biceps (SD) | 0.19 (0.15) | 0.12 (0.04) | 62.6% (7.1% to 118.1%) | 0.028 (0.034) |
| MRI relative T2 signal thoracic paraspinals (SD) | 0.45 (0.17) | 0.31 (0.09) | 42.4% (16.9% to 68.0%) | 0.002 (0.006) |
| MRI relative T2 signal right TA (SD) | 0.38 (0.16) | 0.27 (0.05) | 37.6% (12.4% to 62.8%) | 0.004 (0.011) |
| MRI relative T2 signal left TA (SD) | 0.24 (0.15) | 0.14 (0.05) | 73.3% (26.4% to 120.1%) | 0.003 (0.005) |
Parameter estimates refer to unadjusted differences between patients and controls, with 95% CI in parentheses. Pvalues refer to differences between patients and controls unadjusted and, in parentheses, adjusted for age and gender. Relative T2 signal differences are reported as percentage differences in patients with motor neuron disease relative to controls. Significant results after correction for multiple comparisons are highlighted in bold.
ALSFRS-R, amyotrophic lateral sclerosis functional rating scale-revised; CMAP, compound muscle action potential; MRC, Medical Research Council; MUNIX, motor unit number index; MUSIX, motor unit size index; TA, tibialis anterior.