Thermoregulatory abnormalities are known to occur in demyelinating disorders, yet they are poorly studied (Adamec et al 2018). While a few studies focus on sudomotor dysfunction in multiple sclerosis (MS), data on sudomotor dysfunction and neuromyelitis optica spectrum disorder (NMOSD) are minimal (Kwon et al 2020).
In a paper published in the European Journal of Neurology, Habek and an international group of collaborators (2023) present a cohort of 48 patients with NMOSD to determine the extent of sudomotor dysfunction in this disease. Patients were evaluated using the secretomotor part of the Composite Autonomic Symptom Score 31 (COMPASS-31) and the quantitative sudomotor axon reflex test (QSART). In both, the findings point to a sudomotor dysfunction in above half of the patients - 54% in the COMPASS-31 and 52.1% in the QSART – which was moderate to severe in a third (29.2%).
The authors also compared their findings with those from a historical cohort of people with relapsing–remitting MS. They found differences between groups only in symptomatic sudomotor dysfunction (22.9% in NMOSD vs 1,3% in RRMS) but not in the quantitative evaluation. In a multivariate analysis, predictors for symptomatic sudomotor dysfunction were age and a diagnosis of NMOSD instead of MS.
The authors further suggest that the presence of peripheral unmyelinated fiber dysfunction in NMOSD raises questions regarding the underlying pathophysiological mechanisms of this disorder.
- More than 50% of patients with NMOSD have sudomotor dysfunction
- Sudomotor dysfunction is moderate or severe in one third of the patients
- Sudomotor dysfunction is more often symptomatic in patients with NMOSD compared to patients with RRMS
- Adamec I, Crnošija L, Junaković A, Krbot Skorić M, Habek M. Progressive multiple sclerosis patients have a higher burden of autonomic dysfunction compared to relapsing remitting phenotype. Clin Neurophysiol. Aug 2018;129(8):1588-1594. doi:10.1016/j.clinph.2018.05.009
- Kwon S, Kim YS, Kim J, Kim BJ, Min JH. Clinical and MRI correlates of autonomic dysfunction in neuromyelitis optica spectrum disorder. Mult Scler Relat Disord. Aug 2020;43:102215. doi:10.1016/j.msard.2020.102215
- Habek M, Andabaka M, Fanciulli A, et al. Sudomotor dysfunction in people with neuromyelitis optica spectrum disorders. Eur J Neurol. Sep 2022;29(9):2772-2780. doi:10.1111/ene.15413.
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