Altered sympathetic nervous system response in patients with fibromyalgia (fibrositis syndrome).

Twenty-seven female patients with fibromyalgia and 29 female healthy controls underwent an auditive stimulation test and a left hand cold pressor test at 10 and 4 degrees C. The microcirculatory changes observed, indicate that, as a response to 80 dB, 1000 Hz, 2 seconds sounds and cooling with associated pain, the vasoconstrictory responses are less in patients with fibromyalgia than in normal controls. This could indicate altered sympathetic nervous activity in patients with fibromyalgia and that the cutaneous manifestations previously interpreted as Raynaud's phenomenon should be reconsidered.