Demographic characteristics
| Characteristics | n* | NH (n=7) | n* | Without NH (n=39) | p Value |
|---|---|---|---|---|---|
| Age, mean (SD) | 7 | 12.1 (3.2) | 39 | 10.8 (3.4) | 0.325 |
| Male, n (%) | 7 | 4 (57.1) | 39 | 24 (61.5) | 1.000 |
| Height, mean (SD) | 7 | 149.3 (16.8) | 38 | 145.9 (20.4) | 0.682 |
| Weight, mean (SD) | 7 | 42.4 (16.8) | 38 | 45.3 (23.0) | 0.755 |
| BMI, median (IQR) | 7 | 16.4 (14.3–24.4) | 38 | 19.8 (14.9–22.3) | 0.635 |
| Wheelchair enabled, n (%) | 7 | 3 (42.9) | 38 | 4 (10.3) | 0.124 |
| Diagnosis | 7 | 38 | |||
| Charcot-Marie-Tooth | 1 | ||||
| Spinal muscular atrophy type II | 2 | 3 | |||
| Limb girdle dystrophy | 2 | ||||
| Congenital myotonia | 1 | 4 | |||
| Myasthenic syndrome | 2 | ||||
| Congenital muscular dystrophy | 2 | 4 | |||
| Metabolic myopathy | 1 | 5 | |||
| Nemaline myopathy | 1 | 2 | |||
| Clinical myopathy without confirmed genetic aetiology | 15 | ||||
| FVC, mean (SD) | 7 | 58.4 (39.3) | 38 | 77.5 (24.1) | 0.048 |
| FEV1, mean (SD) | 7 | 55.0 (26.7) | 38 | 78.3 (21.5) | 0.022 |
| MIP, mean (SD) | 7 | 65.0 (39.1) | 34 | 74.5 (37.3) | 0.556 |
| MEP, mean (SD) | 7 | 51.0 (19.4) | 34 | 73.6 (39.5) | 0.107 |
| Baseline CO2 awake, median (IQR) | 7 | 41 (38–43) | 29 | 40 (37–44) | 0.888 |
| Apnoea-hypopnoea index | |||||
| Central | 4 | 5.9 (0.9–12.0) | 6 | 1.5 (0.2–3.1) | 0.352 |
| Obstructive | 3 | 4.2 (4.1–10.9) | 15 | 1.0 (0.6–5.6) | 0.130 |
| Total | 7 | 8.2 (4.2–13.2) | 29 | 2.0 (0.8–4.9) | 0.018 |
| Lowest oxygen saturation | 7 | 89 (80–94) | 27 | 98 (94–99) | 0.015 |
| Baseline oxygen saturation asleep | 7 | 97 (96–97) | 38 | 97 (97–98) | 0.187 |
| Baseline et/tc pCO2 asleep | 7 | 49 (49–53) | 30 | 46 (43–49) | 0.015 |
| Maximum tc/et pCO2 | 7 | 56 (46–58) | 29 | 50 (44–53) | 0.111 |
↵* Indicates the number of participants for whom the data were available. The ranges in the last 7 rows refer to medians and interquartile ranges.
BMI, body mass index; et, end-tidal measurement of carbon dioxide; FEV1, forced expiratory volume in 1 s; FVC, forced vital capacity; MEP, maximal expiratory pressure; MIP, maximal inspiratory pressure; NH, nocturnal hypoventilation; tc, transcutaneous measurement of carbon dioxide. The units are millimeters of mercury.