DIMINISHED AUTONOMIC NERVOUS-SYSTEM RESPONSIVENESS IN RHEUMATOID-ARTHRITIS OF RECENT-ONSET

Objective. To investigate responsiveness of the autonomic nervous syst em in rheumatoid arthritis (RA) of recent onset. Methods. 21 patients (17 women, mean age 55.7 years) and 20 healthy controls (16 women, mea n age 52.7 years) were subjected to 4 tasks eliciting divergent autono mic reactions: film watching, mild physical exercise, cognitive discri mination, and the Stroop color-word interference test. Changes in hear t rate, diastolic (DBP) and systolic (SBP) blood pressure, and skin co nductance relative to pretask baseline values were computed and relate d to erythrocyte sedimentation rate, pain, mobility, and dexterity. Re sults. Mean autonomic levels of patients were normal, as well as auton omic responses to film watching and mild physical exercise. Diminished autonomic responses were observed during cognitive discrimination and during the Stroop test. Blood pressure responses were negatively rela ted to pain severity, but positively to impaired dexterity. Conclusion . Diminished autonomic nervous system response is observed in RA of re cent onset, most clearly in patients with more severe pain. This sugge sts that it is associated with primary pathophysiological mechanisms.