Autonomic Dysfunction In MS

The disturbances of Autonomic CardioVascular reflexes have already been described in patients with Multiple Sclerosis (MS). It seems that these disturbances are the result of reflex pathways impairment in the Central Nervous System.

We have tested 28 patients with MS and control group of 21 healthy volunteers using a set of Autonomic CardioVascular reflex tests. In all patients, zones of DeMyelination have been discovered with Magnetic Resonance Imaging (MRI).

The biggest number of abnormal results was found in Respiratory Sinus Arrhythmia (RSA) test (60.7%) and Cortical Activation test (35.7%). In 11 patients we found abnormal results in 2 or more tests.

Patients with abnormal results in 4 or more tests had clinical impairment of other Autonomic Functions (Urinary Bladder Regulation). The results of Autonomic Dysfunction tests show positive correlation to the MRI findings.

Objective
Patients with definite Multiple Sclerosis (MS) were tested for Autonomic Nervous System (ANS) dysfunction using clinical symptomatology criteria and non-invasive laboratory testing.

Exactly 45.45% of patients exhibited subjective symptoms of Autonomic Dysfunction and 42.42% of patients had abnormal laboratory tests results.

Methods
The Sympathetic ANS tests were abnormal in 30.3% of MS patients and the ParaSympathetic ANS tests were abnormal in 18.18% of MS patients.

The most sensitive test for the presence of Autonomic Dysfunction was the Sympathetic Skin Response.

Conclusion
Autonomic Dysfunction was often subclinical and we conclude that it is preferable to combine several tests for a more thorough and accurate evaluation of the ANS impairment in MS.