Plasma nitrite levels, total antioxidant status, total oxidant status, and oxidative stress index in patients with tension-type headache and fibromyalgia.

OBJECTIVES: Tension-type headache (TTH) and fibromyalgia syndrome (FM) are worldwide seen chronic pain syndromes of unknown etiology. Despite the growing body of data on pathophysiology and generation mechanisms of pain; our knowledge on pain mechanisms in both FM and TTH is yet to be limited. PATIENTS AND METHODS: We investigated the plasma nitrite levels, total antioxidant status (TAS), total oxidant status (TOS), and oxidative stress index (OSI) in 35 TTH, 33 FM patients and 31 healthy controls.
RESULTS: The mean plasma nitrite levels and TAS levels were significantly low and OSI was found to be significantly high in TTH and FM groups compared to the control group (p=0.001, p=0.001, p=0.001 and p=0.001, respectively). The mean serum TOS levels were also significantly higher in FM group according to the control group (p=0.034), but there was not a significant difference between TTH and control groups (p=0.066).
CONCLUSION: These results indicated that; FM and TTH patients revealed higher oxidative stress index and lower total nitrite levels than healthy controls. We conclude that oxidative stress may have a role in the pathophysiological mechanisms of TTH and FM, although, whether it is the cause or the consequence, is not clear.