PTGS1 and type 2 diabetes mellitus: The main findings of this study are that—(i) T2DM and primary HC patients show comparable prevalence of high on-aspirin platelet reactivity when the non-COX-1-dependent CEPI PFA-100 and COX-1-dependent LTA-AA, LTA-collagen, urinary 11-dhTXB2 assays were performed; (ii) compared to HPR-, HPR+ subjects with T2DM or HC showed an imbalance of redox status corresponding to a lower activity of the oxidant scavenger SOD; (iii) SOD positively correlates with CEPI PFA-100 closure times and a stepwise linear regression yielded a model in which only SOD predicts platelet reactivity in both T2DM and HC.