Results
Thirty of the forty-one (73%) patients approached were enrolled and able to perform spirometry in both sitting and supine positions. The mean age at testing was 11.5 years (SD ±3.0). Thirty controls without respiratory or sleep pathology were recruited Characteristics of the two study groups are shown in Table 2.
Specific neuromuscular diagnoses were heterogeneous, with the majority (17/30; 57%) having Duchenne Muscular Dystrophy [DMD] (Table 1). Children with NMD were further categorized as unsupported in sleep (i.e. spontaneously breathing: N=22) or established on nocturnal NIV [N=8].