Autonomic (sympathetic) nervous system involvement in rheumatoid arthiritis patients.

Fifty Rheumatoid arthritis (RA) patients between the age group of 20 to 60 years were investigated for sympathetic autonomic functions using standard tests. All the patients liable to develop dysautonomia or having a treatment interfering with autonomic nervous system were excluded. Previous studies to evalute sympathetic nervous system involvement used only a single test like sweating response, orthostatic test. In the present study 3 tests of sympathetic nervous system evaluation have been used. The evaluation was done by cardiovascular tests like orthostatic test, sustained hand grip and cold pressor test. A control series of 50 healthy subjects was tested to determine abnormal threshold for each one of the 3 tests. The reference value of Ewing and Clark were used to interpret the results of the tests. Sympathetic dysfuction was found in 26% of rheumatoid arthritis patients.