The use of handheld spirometers in adult cohorts is established. Recently there has been increased interest in the paediatric field (1), fueled during the COVID-19 pandemic by the need to protect more vulnerable patient groups and reducing hospital footfall, whilst maintaining good clinical care.

The aim of this prospective, cross-sectional study was to evaluate the reproducibility of home spirometry in a group of children with neuromuscular disease (NMD).

28 children enrolled over a period of 12 months. Median age (range) was 12.6 years old (7-16). 18 children had Duchenne muscular dystrophy, 8 had myotonic dystrophy and 2 had spinal muscular atrophy.  Median number of spirometry attempts was significantly higher in the lung function laboratory (LFL) compared to home (9 Vs 3, p= <0.0001). 75% of home attempts and 48% of LFL based attempts were Grade U (2). 18/28 children were able to complete at least one successful effort in both environments (LFL and home).  Paired Forced Vital Capacity (FVC) z scores in LFL and home showed significant difference (median of differences z=1.370, p=0.0154).

Figure 1: Home vs Lab FVC z score

This study shows that in a small, selected group of children with NMD, quality of spirometry was low both at home and in the LFL. FVC at home was significantly different to laboratory based tests and is unlikely to be helpful in long term management of this group of patients.