Autonomic nervous function in headache

Abstract

We can find a lot of signs and symptoms due to the disturbance of autonomic nervous system in patients with migraine. The purpose of our study is to clarify the autonomic function in migraine. The autonomic nervous function in patients with migraine was studied during headache-free intervals. The following observations were made: (1) a decrease in overshoot in Valsalva's maneuver; (2) orthostatic hypotension; (3) low levels of plasma norepinephrine in the steady state; (4) failure in elevation of the plasma norepinephrine level after head-up tilting; (5) dilatation of the pupils after instillation in the eye of 1.25% epinephrine. The above findings suggest that patients with migraine show sympathetic hypofunction with denervation hypersensitivity of the iris. When we evaluated the orthostatic hypotension during headache period in nine patients with migraine, we could not find any orthostatic hypotension. These phenomenon suggests that sympathetic hypofunction disappeared in patients with migraine during headache. As a next step, sweating function in patients with migraine were examined during headache-free intervals. Our results suggest that sweating function are impaired in patients with migraine. When we investigate the cerebral blood flow in patient with migraine during attack, low blood flow in hypothalamus was observed. When headache was disappeared, hypothalamus blood flow was recovered and increased more than other area. Cerebrospinal hypovolemia patients often showed orthostatic headache. Among cerebrospinal hypovolemia patients we can find many patients with postural tachycardia syndrome, who showed low production of cerebrospinal fluid probably due to sympathetic hyperactivity.