Table 2 M50 and D50 median separation.

From: Motor unit number index (MUNIX) loss of 50% occurs in half the time of 50% functional loss according to the D50 disease progression model of ALS

 

Same separation

Differing separation

Differing separation

Sig.

Low M50 and high D50

High M50 and low D50

n = 164

n = 58

n = 29

n = 29

M50 in months

14.9 (8.19–29.7)

14.6 (10.7–22.0)

10.8 (8.10–13.0)

21.7 (16.8–27.7)

***

MUSIX200 in months

19.0 (10.1–34.0)

13.5 (8.83–19.7)

10.8 (8.19–13.7)

18.6 (13.2–23.3)

***

CMAP50 in months$

17.6 (9.69–38.6)

17.5 (11.2–23.7)

12.8 (8.85–15.4)

22.9 (18.3–30.8)

***

D50 disease progression model parameters

 rD50 at MUNIX

0.30 (0.20–0.41)

0.26 (0.13–0.39)

0.16 (0.10–0.26)

0.39 (0.23–0.51)

***

 D50 in months

28.1 (17.3–48.2)

28.6 (20.3–38.7)

38.5 (31.0–47.5)

20.7 (15.6–25.6)

***

Demographic and clinical parameters

 Age at MUNIX

66.3 (58.7–72.4)

64.1 (57.5–72.4)

59.3 (54.9–66.4)

67.1 (58.7–75.4)

**

 Gender (female/male)

74/90

23/35

7/22

16/13

 

 Disease duration at MUNIX in months

15.7 (8.73–30.7)

13.4 (8.88–19.3)

13.6 (9.52–16.9)

13.1 (7.89–23.9)

*

 ALS phenotype

  Classic

92

36

23

13

**

  Bulbar

57

22

6

16

**

  Flail arm

4

0

0

0

 

  Flail leg

2

0

0

0

 

  Pyramidal

4

0

0

0

 

  PLMN

5

0

0

0

 

 ALSFRS-R Subscores

  Bulbar

11 (8–12)

10 (7–12)

11 (11–12)

7 (6–10)

***

  Fine motor

9 (6–11)

10 (7–12)

10 (9–12)

8 (5–11)

**

  Gross motor

9 (5–11)

9 (6–11)

9 (7–12)

8 (5–11)

 

  Respiratory

12 (10–12)

12 (10–12)

12 (11–12)

10 (8–12)

***

  1. Values are given as median and interquartile range or numbers.
  2. ALS amyotrophic lateral sclerosis, ALSFRS-R revised amyotrophic lateral sclerosis functional rating scale, CMAP compound muscle action potential, MUNIX motor unit number index, MUSIX motor unit size index, LSPR laboratory-supported probable, PLMN pure lower motor neuron, Sig significant difference between the “differing separation” subgroups (*p ≤ 0.05, **p ≤ 0.01, ***p ≤ 0.001) $related to n = 160 at “same separation” and n = 56 at “differing separation”/n = 27 at “high M50 and low D50” because 6 patients had no loss of function in comparison to the mean of CMAP of healthy controls. Phenotype in accordance to Chio et al.25.