R-R variations in Guillain-Barré syndrome: a test of autonomic dysfunction.

As we have earlier shown, variations in the R-R interval of the ECG can be used as a measure of autonomic function. This test was applied to 6 patients with Guillain-Barré syndrome at different times during the course of the disease. Severe but temporary impairment of autonomic function was found, which was maximal at 2-6 weeks after the onset of clinical symptoms and gradually improved to normal levels over a period of 3-18 months. This paralleled clinical recovery. The results suggest that this test of R-R variations is a reliable method for establishing and following an autonomic dysfunction in patients with Guillain-Barré syndrome.