Whole-Brain Atrophy Rate in Idiopathic Parkinson’s Disease, Multiple System Atrophy, and Progressive Supranuclear Palsy
Table 2
Baseline, follow-up scores, and estimates of the sample sizes in PSP () and MSA ().
Baseline score
Repeat score
Annual change
Number of subjects required per arm (20% reduction)
Number of subjects required per arm (50% reduction)
PSP
Whole-brain atrophy rate, %
N/A
N/A
1.26 ± 0.5
83
14
UPDRS III
37 ± 14.5
39.2 ± 19
2.3 ± 13
168
27
CGI-S
4.4 ± 0.5
4.6 ± 0.8
0.2 ± 0.6
4889
1048
H&Y
2.6 ± 0.7
3.3 ± 0.9
0.7 ± 0.8
631
101
FAB
10 ± 5.3
10.7 ± 7.8
0.7 ± 4.6
22688
3630
MSA
Whole-brain atrophy rate, %
N/A
N/A
1.65 ± 1.1
234
38
UPDRS III
45.3 ± 13
52.6 ± 10
7.1 ± 9.4
921
148
CGI-S
4.6 ± 0.5
5.1 ± 3.5
0.5 ± 0.5
621
100
H&Y
3.1 ± 0.8
3.7 ± 0.4
0.7 ± 0.7
526
85
FAB
12.0 ± 4.2
10.8 ± 4.4
−1.1 ± 3.4
5020
804
Difference between the baseline and repeat score with a value < 0.05 (Wilcoxon’s signed rank test). SIENA gives the whole-brain atrophy rate for image pairs and does not estimate the baseline and follow-up brain volume. All of the values are the mean ± SD.
