Association between oxidative damage markers and self-reported temporomandibular dysfunction symptoms in patients with chronic fatigue syndrome.

Full blood counts, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP),haematinics and markers for oxidative stress were measured on thirty- three patients diagnosed with chronic fatigue syndrome (CFS) and twenty- seven age and sex matched controls. The CFS patients had increased prevalence of symptoms of temporomandibular dysfunction (TMD). Jaw muscle pain was associated with increases in methaemoglobin (P < .002), ferritin (P < .02) and malondialdehyde (P <.007) whilst temporomandibular joint (TMJ) clicking and/or locking was associated with increases in methaemoglobin (P < .001), malon- dialdehyde (P < .05) andvitamin B12 (P < .02) levels. Multiple regression analysis found methaemoglobin to be the principle component associated withTMD symptoms in the CFS patients.Increases in scalar severity responses to jaw muscle pain and TMJ clicking and/or locking were positively correlated with methaemoglobin by multiple regression.These data indicate that oxidative stress due to excess free radical formation was associated with jaw muscle pain in CFS patients and suggest that these symptoms were likely to be associated with a pathogen-associated aetiology.