Fatigued patients with multiple sclerosis can be discriminated from healthy controls by the recordings of a newly developed measurement system (FAMOS): a pilot study.

Purpose: To explore the difference between fatigued patients with multiple sclerosis (MS) and matched healthy controls by applying a newly developed physiological and functional data recording system.

Methods: A portable wireless measurement system, named FAtigue MOnitoring System (FAMOS), has been developed, which can continuously measure electrocardiogram (ECG), body skin temperature, electromyogram, and motion parameters. In a pilot study, 17 fatigued MS patients (fatigue severity scale (FSS) = 53.9 SD 5.4) and 9 healthy matched controls (FSS = 27.2 SD 6.8) were recruited and monitored by FAMOS during the execution of functional (36 m walk test, 5- and 50-repetition sit-to-stand test) and cognitive (short-term memory tests) tests. Furthermore, oxygen saturation (SPO(2)) was measured during the functional and cognitive tests and during rest periods between these tests.

Results: Recordings from FAMOS indicate that fatigued MS patients have reduced standard deviation (SD) of the heart rate (HR) during the short-term memory test, reduced high frequency (HF) component power spectrum (representing parasympathetic activation) at rest after walk test, and higher ratio of low frequency (LF) to HF (LF/HF) during 50-repetition sit-to-stand test.

Conclusions: FAMOS recordings can discriminate fatigued MS patients from healthy controls. The data indicate that fatigued MS patients have vagus nerve dysfunction during cognitive tests and disturbed sympathovagal balance during stressful physical tests. [Box: see text].