Objective: To investigate the involvement of the autonomic nervous system (ANS) in rheumatoid arthritis (RA), which is rarely discussed.
Methods: Fifty cases of RA were selected, excluding all patients liable to develop dysautonomia or having a treatment interfering with ANS. They were investigated by cardiovascular tests of heart rate variations in deep breathing, Valsalva maneuver and orthostatic change in posture. These quantified tests were reported as ratios: breathing, Valsalva and 30/15. A control series of 82 healthy subjects was tested to determine the abnormal threshold for each one of the 3 tests and allowed a correlative study. Dysautonomia was defined when 2 of the 3 tests were pathological. According to these criteria, 30 patients with RA with ANS dysfunction were retained.
Results: The clinical examination of these patients showed no neurological sign or autonomic sign but there was an inflammatory syndrome. Rheumatoid factors (RF) were frequently present as were slowly progressive articular destructions. The statistical study revealed a significant difference between the series of RA patients and the control series, only for the Valsalva maneuver (p < 0.01) and there was no obvious correlation between ANS dysfunction in RA and markers of inflammation, presence of RF, duration of disease or degree of articular destructive lesions.
Conclusion: Our study is in agreement with the literature which reports an ANS involvement in RA with a same frequency but remaining primarily subclinical and probably isolated from other peripheral or central nervous system damage. The physiopathology of this form of dysautonomia is discussed and an immunological mechanism is suggested.