SUBCLINICAL AUTONOMIC DISTURBANCES IN MULTIPLE-SCLEROSIS

We compared results from non-invasive autonomic testing [sympathetic s kin responses (SSR), heart beat variation during deep breathing, and o rthostatic manoeuvre with transcranial Doppler monitoring in 22 patien ts] with motor and somatosensory evoked potentials (MEP and SEP) in 30 unselected patients with multiple sclerosis. We found a similarly hig h yield of pathological results for SSR, MEP and SEP (66.7%, 65.5%, an d 69%, respectively). When analysed for each limb (n = 120), SSR were highly correlated with MEP and SEP (for both P < 0.001). Heart beat va riation was reduced in only 3 patients. In 4 of 22 patients orthostati c manoeuvre induced a pathological decrease in cerebral blood flow vel ocity despite normal systemic blood pressure being maintained. We conc lude that SSR may be a useful additional diagnostic tool in patients w ith multiple sclerosis. Cerebral dysautoregulation is a lather frequen t finding, although its significance is not known.