Table 2.
Disease progression in 66 adults with Pompe disease: annual changes in muscle strength and pulmonary function across various subgroups
| MRC sumscore | HHD sumscore | QMFT score | FVC sitting position | FVC supine position | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
Total group |
n |
Annual change (%/year) |
95% CI |
n |
Annual change (%/year) |
95% CI |
n |
Annual change (%/year) |
95% CI |
n |
Annual change (%/year) |
95% CI |
n |
Annual change (%/year) |
95% CI |
| |
65 |
−1.30 |
−1.95 to −0.66 |
55 |
−2.6 |
−3.72 to −1.45 |
62 |
0.05 |
−0.76 to 0.86 |
59 |
−1.04 |
−2.14 to 0.06 |
54 |
−1.30 |
−2.42 to −0.19 |
|
Subgroups |
n |
Annual change (%/year) |
|
n |
Annual change (%/year) |
|
n |
Annual change (%/year) |
|
n |
Annual change (%/year) |
|
n |
Annual change (%/year) |
|
| Gender | |||||||||||||||
| • Female |
36 |
−1.41 |
|
31 |
−2.97 |
|
37 |
−0.22 |
|
36 |
−1.38 |
|
33 |
−2.27 |
|
| • Male |
29 |
−1.08 |
|
24 |
−1.99 |
|
25 |
0.57 |
|
23 |
−0.45 |
|
21 |
0.35 |
|
| Age at study entry a | |||||||||||||||
| • < 50 years |
34 |
−1.39 |
|
31 |
−2.06 |
|
33 |
−0.17 |
|
33 |
−1.34 |
|
31 |
−2.22 |
|
| • ≥ 50 years |
31 |
−1.21 |
|
24 |
−3.29 |
|
29 |
0.30 |
|
26 |
−0.69 |
|
23 |
−0.08 |
|
| Disease duration at study entry a | |||||||||||||||
| • < 15 years |
34 |
−0.70c |
|
31 |
−1.95e |
|
34 |
−0.07 |
|
35 |
−1.36 |
|
33 |
−1.37 |
|
| • ≥ 15 years |
31 |
−2.09c |
|
24 |
−4.18e |
|
28 |
0.17 |
|
24 |
−0.60 |
|
21 |
−1.16 |
|
| FVC (sitting) at study entry | |||||||||||||||
| • ≥ 80% predicted |
33 |
−0.62d |
|
32 |
−1.43f |
|
33 |
−0.21 |
|
33 |
−1.09 |
|
31 |
−1.59 |
|
| • < 80% predicted |
32 |
−2.21d |
|
23 |
−4.52f |
|
29 |
0.31 |
|
26 |
−0.89 |
|
23 |
−0.92 |
|
| Ventilation at study entry | |||||||||||||||
| • No |
49 |
−1.12 |
|
46 |
−2.50 |
|
50 |
0.24 |
|
50 |
−1.30 |
|
47 |
−1.50 |
|
| • Yes |
16 |
−1.83 |
|
9 |
−3.55 |
|
12 |
−0.70 |
|
9 |
1.07 |
|
7 |
0.32 |
|
| Wheelchair use at study entry | |||||||||||||||
| • No |
47 |
−0.94 |
|
44 |
−2.28 |
|
47 |
−0.39 |
|
47 |
−0.98 |
|
43 |
−0.99 |
|
| • Yes |
18 |
−2.36 |
|
11 |
−3.92 |
|
15 |
1.44 |
|
12 |
−1.22 |
|
11 |
−2.57 |
|
| MRC / HHD sum score at study entry b | |||||||||||||||
| • < 33rd percentile |
18 |
−1.27 |
|
10 |
−2.06 |
|
20 |
0.49 |
|
12 |
−0.30 |
|
9 |
−1.59 |
|
| • 33rd to 66th percentile |
23 |
−1.31 |
|
22 |
−4.34 |
|
23 |
−0.06 |
|
23 |
−2.40 |
|
21 |
−2.01 |
|
| • ≥ 66th percentile | 24 | −0.98 | 23 | −1.56 | 19 | −0.41 | 24 | −0.34 | 24 | −0.63 | |||||
MRC: Medical Research Council; HHD: Hand-Held Dynamometry; QMFT: Quick Motor Function Test; FVC: Forced Vital Capacity; CI: confidence interval. a the median was taken as the cut-off point. b categorization in tertiles. n represents the number of patients for whom data were available for each specific measurement. For muscle strength, no sumscore was calculated if measurements for three or more individual muscle groups were missing (e.g. due to severity of muscle weakness or injury). For seven invasively ventilated patients no reliable measurements of FVC could be performed. Neither could testing in the supine position be endured by 5 patients whose pulmonary function was already severely restricted in sitting position.
Data shown are mean annual changes (percentage points per year) as calculated by repeated measures ANOVA. For MRC sumscore and HHD sumscore there were significant differences between groups based on disease duration and FVC at study entry: c) p=0.04, d) p=0.01, e) p<0.01, and f) p<0.01.