Inspiratory muscle strength monitoring is crucial in patients with neuromuscular disorders. The sniff nasal inspiratory pressure (SNIP) and maximal inspiratory pressure (PI,max) are usually measured. The present study investigated whether the test yielding the best value at baseline continued to yield the best value during follow-up. The present study included 25 patients with Duchenne muscular dystrophy (DMD) and 61 with myotonic muscular dystrophy (MMD). SNIP and PI,max were measured at baseline and then annually. At baseline, SNIP was lower than PI,max in 20 (80%) DMD patients and 32 (52%) MMD patients. During follow-up in DMD patients, changes in the best method always occurred from SNIP to PI,max. In MMD patients, when SNIP was better than PI,max at baseline, SNIP was usually (88%) better during follow-up, whereas a better PI,max than SNIP at baseline was frequently (50%) followed by a shift to SNIP. Maximal inspiratory pressure may be sufficient for monitoring inspiratory muscle function in Duchenne muscular dystrophy adults. In myotonic muscular dystrophy, the marked variability in the test yielding the best value at baseline indicates a need for performance of both tests at baseline. However, when sniff nasal inspiratory pressure measurement yields the best value at baseline, using sniff nasal inspiratory pressure alone during follow-up may be appropriate. Copyright©ERS Journals Ltd 2008.
Terzi, N., Orlikowski, D., Fermanian, C., Lejaille, M., Falaize, L., Louis, A., … Lofaso, F. (2008). Measuring inspiratory muscle strength in neuromuscular disease: One test or two? European Respiratory Journal, 31(1), 93–98. https://doi.org/10.1183/09031936.00094707