Altered autonomic function in patients with arthritis or with chronic myofascial pain.

Dynamic autonomic function tests (pupillary light reflex, Valsalva maneuver, and mental arithmetic) were used to evaluate autonomic function (pupil size, heart rate, and skin conductance) in patients with inflammatory arthritis or with chronic myofascial pain. Physiological responses in both groups of patients suggest concurrent increases in tonic pupillary autonomic activity (sympathetic and parasympathetic), with a relative sympathetic dominance, and a decrease in tonic parasympathetic cardiovascular activity. Furthermore, in the arthritis group, the data suggest decreased cardiovascular parasympathetic reaction and enhanced sudomotor reaction.