Relationship between neck weakness in motor neurone disease and respiratory function: a retrospective study

Abstract

AIMS: The primary aim was to explore the relationship between neck weakness in people with motor neurone disease (MND) and their respiratory function. The secondary aim was to identify whether neck weakness can be a prognostic factor. METHODS: This was a retrospective observational cohort study. Data was collected from patient records on MND characteristics, neck weakness, respiratory function, and noninvasive ventilation (NIV) use. Multivariate modeling explored the effect of neck weakness on respiratory variables. RESULTS: MND-related neck weakness was evident in 41% of 324 participants. Fifty-four percent used NIV and 17% became dependent on NIV during disease progression. The presence of neck weakness in MND was predictive of time to respiratory function decline, for respiratory outcomes (forced vital capacity (FVC) <65%, FVC <50% and NIV use) as well as having an effect on time to death. Median time from neck weakness onset to death was 8 months (IQR 10 months; range 0 to 60 months) with bulbar onset the quickest, median of 7 months (IQR 7 months, range 0 to 43 months). CONCLUSIONS: The presence of neck weakness is associated with a more rapid respiratory function decline in MND. In addition, neck weakness can be considered a prognostic factor in MND survival.