Table 4.
Time course of disease progression based on the SARA, BI, IDR-ICARS and IDR-BI scores
| Follow-up year | −4 | −3 | −2 | −1 | Registration | 1 | 2 | 3 | Total |
|---|---|---|---|---|---|---|---|---|---|
| N (follow-up rate%) |
29 |
35 |
38 |
40 |
46(100) |
44(96) |
44(96) |
43(93) |
177* |
| Death, n |
|
|
|
|
0 |
1 |
0 |
1 |
2 |
| Withdrawal, n |
|
|
|
|
0 |
1 |
0 |
0 |
1 |
| SARA score, points |
|
|
|
|
15.9 ± 7.1 |
16.8 ± 6.9a |
18.2 ± 7.2a |
19.1 ± 6.9a |
17.5 ± 7.1 |
| ΔSARA, points |
|
|
|
|
0 |
1.35 ± 1.70 |
2.78 ± 2.78 |
3.73 ± 3.17 |
n/a |
| ΔSARA/year, points/y |
|
|
|
|
0 |
1.35 ± 1.70 |
1.39 ± 1.39 |
1.24 ± 1.06 |
1.33 ± 1.40 |
| BI score, points |
|
|
|
|
77.4 ± 22.4 |
77.4 ± 22.3b |
73.8 ± 23.7b |
75.0 ± 23.2 |
75.9 ± 22.8 |
| IDR-ICARS score, points |
13.9 ± 5.9 |
13.7 ± 5.9 |
14.1 ± 6.0c |
14.6 ± 5.7 |
14.8 ± 6.0 |
15.0 ± 5.4b |
16.0 ± 5.7b |
16.2 ± 5.6 |
14.9 ± 5.8 |
| ΔIDR-ICARS, points |
−2.28 ± 3.59 |
−2.06 ± 3.27 |
−1.29 ± 2.98 |
−0.50 ± 2.32 |
0 |
0.59 ± 1.65 |
1.59 ± 2.34 |
1.77 ± 2.79 |
n/a |
| ΔIDR-ICARS/year, points/y |
−0.57 ± 0.90 |
−0.69 ± 1.09 |
−0.64 ± 1.49 |
−0.50 ± 2.32 |
0 |
0.59 ± 1.65 |
0.80 ± 1.17 |
0.59 ± 0.93 |
0.63 ± 1.45d |
| IDR-BI score, points | 37.1 ± 14.0 | 38.6 ± 14.2 | 38.4 ± 13.8c | 37.4 ± 14.1 | 36.7 ± 15.1 | 37.6 ± 15.0 | 34.9 ± 14.8b | 35.8 ± 14.9 | 36.3 ± 14.9 |
Where applicable, the values are given as the mean ± standard deviation.
Comparisons of the IDR-ICARS, IDR-BI, SARA, and BI scores of each year were made by using the Friedman test followed by the Wilcoxon signed rank test as a post hoc test.
Abbreviations: BI = Barthel Index; ICARS = International Cooperative Ataxia Rating Scale; IDR = Intractable Diseases Research; n/a = not applicable; SARA = Scale for the Assessment and Rating of Ataxia.
IDR-BI = total points of 6 items from the BI assessed by the IDR registry.
IDR-ICARS = total points of 5 items from the ICARS assessed by the IDR registry.
ΔIDR-ICARS and ΔSARA = differences between the scores obtained at the follow-up evaluations and those obtained at registration for the IDR-ICARS and SARA, respectively.
aP < .001, versus the previous year for the prospective study.
bP < .05 versus the previous year for the prospective study.
cP < .05 versus the next year for the retrospective study.
dTotal of the IDR-ICARS/year calculated with the absolute value of each ΔIDR-ICARS/year excluding that of the registration year.
*Total number of evaluations conducted during the prospective arm of the study.