Is oxidative stress a factor in the pathogenesis of subacute thyroiditis?

In a performed study, selenium levels were detected to be lower in subacute thyroiditis (SAT). This outcome suggests that the oxidant-antioxidant system may play a role in the aetiopathogenesis of SAT, as is the case for many other diseases. The aim of the present study was to detect whether any association exists between SAT and oxidative stress, and to determine the factors of a possible association. Twenty-five patients who were newly diagnosed with SAT and 30 healthy volunteers were enrolled in the study. Total antioxidant status (TAS), total oxidant status (TOS), oxidative stress index (OSI), paraoxonase 1 (PON1), and dynamic thiol/disulphide [native thiol (NT), total thiol (TT), disulphide (DS), DS/TT, DS/NT, and NT/TT] levels of the participants were evaluated. Total thiol and NT levels were found to be lower in the SAT group (p < 0.001). DS/NT and DS/TT levels were significantly higher in the patients with SAT, whereas NT/TT levels were lower (p < 0.05). A negative correlation was detected between C-reactive protein (CRP) and TAS, whereas a positive correlation was detected between CRP and OSI. There was a negative association between TSH and TAS only in the partial correlation analysis by adjusting for age, white blood cell count, neutrophil (Neu) level, CRP, and erythrocyte sedimentation rate (ESR) (r = -0.481, p = 0.043). Thiol levels are significantly decreased and thiol/disulphide homoeostasis is disrupted in patients with SAT. The present study has presented for the first time that there may be an association between SAT and oxidative stress.