Peripheral and central nervous changes in patients with rheumatoid arthritis in response to repetitive painful stimulation

It has been observed that patients with rheumatoid arthritis (RA) respond d ifferently to repetitive painful stimulation. The present study investigate d whether this is related to the peripheral or central nervous nociceptive system. EEG-derived potentials and the negative mucosal potential (NMP) fro m the respiratory epithelium were recorded in response to painful intranasa l stimulation with gaseous CO2. Differences between groups (12 RA patients, 12 controls) were found when stimuli were presented at short intervals. Wh ile the NMP did not differ between groups, patients had larger cortical res ponses to the first stimuli of a series of painful stimuli. This may indica te that in RA central nervous changes of nociceptive processing are present . (C) 2000 Elsevier Science B.V. All rights reserved.