Wei et al reported a nomogram for predicting survival for a patient with amyotrophic lateral sclerosis (ALS). The authors are from Sichuan University in Chengdu, China.
Patient selection: amyotrophic lateral sclerosis (ALS)
Parameters:
(1) age at onset
(2) body mass index (BMI) in kg per square meter
(3) rate of disease progression, based on changes in the ALSFRS-R per month
(4) NIPPV (noninvasive positive pressure ventilation)
(5) hemoglobin A1c in percent
(6) serum creatinine in µmol/L
(7) serum CK in U/L
rate of progression =
= (48 - (ALSFRS-R at baseline visit)) / (months between symptom onset and first visit)
|
Parameter |
Finding |
Points |
|
age in years at onset |
< 40 years |
22.9 |
|
|
40 to 44.9 |
19.5 |
|
|
45 to 49.9 |
16.3 |
|
|
50 to 54.9 |
13 |
|
|
55 to 59.9 |
9.8 |
|
|
60 to 64.9 |
6.5 |
|
|
65 to 70 |
3.3 |
|
|
> 70 |
0 |
|
BMI |
< 18 kg per sq m |
0 |
|
|
18 to 19.99 |
7.1 |
|
|
20 to 21.99 |
10.5 |
|
|
22 to 23.99 |
21.7 |
|
|
24 to 25.99 |
28.7 |
|
|
26 to 28 |
36.3 |
|
|
> 28 |
43.4 |
|
NIPPV |
no |
0 |
|
|
yes |
22.6 |
|
progression |
< 0.5 |
100 |
|
|
0.5 to 0.99 |
80 |
|
|
1 to 1.49 |
60 |
|
|
1.5 to 1.9 |
40 |
|
|
2 to 2.5 |
20 |
|
|
> 2.5 |
0 |
|
hemoglobin A1c |
< 5 percent |
18.6 |
|
|
5 to 5.49 |
14.9 |
|
|
5.5 to 5.99 |
11.2 |
|
|
6 to 6.49 |
7.4 |
|
|
6.5 to 7 |
3.7 |
|
|
> 7 |
0 |
|
serum creatinine |
< 40 µmol/L |
0 |
|
|
40 to 59.99 |
6.2 |
|
|
60 to 80 |
12.4 |
|
|
> 80 |
18.6 |
|
CK |
< 50 U/L |
0 |
|
|
50 to 99.99 |
6 |
|
|
100 to 240 |
12 |
|
|
> 240 |
18 |
total score =
= SUM(points for all of the parameters)
Interpretation:
• minimum score: 0
• maximum score: 243.9
value of X =
= (0.06108 * (score)) - 8.672
probability of longer survival =
= 1 / (1 + EXP((-1) * X))
Performance:
• The area under the ROC curve is 0.92.
