Cardiac autonomic dysfunction in relapsing-remitting multiple sclerosis during a stable phase.

The autonomic cardiovascular system was studied by means of autonomic tests and heart rate variability related to body movements during sleep, in 20 patients with relapsing-remitting multiple sclerosis in a stable phase and in 9 normal subjects. Responses to autonomic tests in multiple sclerosis and control subjects were similar. Heart rate variability, instead, showed a lower degree of adaptability in patients with multiple sclerosis than in controls during sleep, because of sympathetic system dysfunction. No significant correlation between magnetic resonance lesions and cardiovascular sleep indexes was found.