Respiratory function tests at the start of nusinersen (baseline) compared with 1 year: within-participant difference analysed by Mann-Whitney U test
| Respiratory variable | SMA type | ||||||||
| SMA type 2 (n=12) | SMA type 3 (n=8) | Combined SMA types 2 and 3 (n=20) | |||||||
| Baseline | 1 year | P value | Baseline | 1 year | P value | Baseline | 1 year | P value | |
| FVC Z-score Mean (SD) | n=12 −4.88 (2.22) | n=11 −4.85 (2.30) | 0.85 | n=7 −0.16 (1.40) | n=8 −0.44 (1.53) | 0.82 | n=19 −3.15 (3.03) | n=19 −2.99 (2.98) | 0.99 |
| FVC % predicted Mean (SD) | n=12 44.58 (23.22) | n=11 44.82 (24.09) | 0.88 | n=7 98.14 (17.58) | n=8 94.88 (19.48) | 0.73 | n=19 64.32 (33.72) | n=19 65.89 (33.39) | 1.00 |
| Rrs8 Z-score Mean (SD) | n=9 1.44 (1.46) | n=5 1.52 (1.4) | 0.95 | n=8 0.37 (0.92) | n=6 0.02 (1.83) | 0.19 | n=17 0.93 (1.31) | n=11 0.70 (1.89) | 0.44 |
| Xrs8 Z-score Mean (SD) | n=9 1.04 (1.22) | n=5 1.38 (2.47) | 0.95 | n=8 0.76 (1.40) | n=6 0.33 (1.59) | 0.27 | n=17 0.91 (1.27) | n=11 0.80 (2.00) | 0.40 |
| LCI Median (25%–75%) | n=9 8.13 (7.82–10.09) | n=7 9.31 (7. 37–10.21) | 0.67 | n=7 7.82 (7.09–8.76) | n=6 6.93 (6.32–7.42) | 0.06 | n=16 8.1 0 (7.63–10.00) | n=13 7.42 (7.11–9.31) | 0.14 |
| FRC (L) Median (25%–75%) | n=9 0.9 (0.8–1.1) | n=5 1.0 (0.9–1.1) | 0.95 | n=8 1.1 (0.8–1.6) | n=6 1.4 (1.1–2.2) | 0.89 | n=16 1.0 (0.8–1.1) | n=13 1.1 (0.9–1.1) | 0.90 |
| PCF (L/min) Median (25%–75%) | n=8 156.9 (116.7–216.3) | n=8 128.7 (111.9–177.9) | 0.43 | n=5 242.4 (237.0–322.3) | n=5 242.4 (237.0–353.4) | 0.17 | n=13 215.4 (147.6–242.4) | n=13 208.8 (119.4–254.4) | 1.00 |
| SNIP (cm H2O) Median (SD) | n=9 41.0 (27.0–73.0) | n=7 44.0 (28.0–73.0) | 0.74 | n=5 76.5 (57.0–83.0) | n=5 83.0 (68.0–92.0) | 0.61 | n=14 57.0 (28.0–73.0) | n=12 68.0 (44.0–86.0) | 0.51 |
| MIP Z-score Mean (SD) | n=8 −1.09 (1.23) | n=8 −1.24 (1.62) | 0.49 | n=5 0.03 (0.75) | n=5 0.04 (0.96) | 0.92 | n=13 −0.66 (1.18) | n=13 −0.758 (1.51) | 0.64 |
| MEP Z-score Mean (SD) | n=8 −2.61 (1.12) | n=8 −3.16 (0.38) | 0.49 | n=5 −1.34 (0.91) | n=5 −0.93 (1.21) | 0.25 | n=13 −2.12 (1.19) | n=13 −2.30 (1.36) | 0.78 |
FRC, functional residual capacity; LCI, Lung Clearance Index; MEP, mean expiratory pressure; MIP, mean inspiratory pressure; PCF, peak cough flow; Rrs8, respiratory resistance at 8 Hz; SMA, spinal muscular atrophy; Xrs8, respiratory reactance at 8 Hz.