BACKGROUND: Involvement of cyclooxygenase (COX)-mediated inflammation in type 2 diabetes has not been studied, and the association between cytokine-mediated inflammation and diabetes is not fully clarified. METHODS AND RESULTS: 15-Keto-dihydro-prostaglandin F2alpha (a metabolite of prostaglandin F2alpha and an indicator of COX-mediated inflammation), high-sensitivity C-reactive protein (CRP), serum amyloid protein A (SAA), 8-iso-PGF2alpha (a nonenzymatic, free radical product of arachidonic acid and an indicator of oxidative stress), and alpha-tocopherol were measured in a population-based sample of 77-year-old men (n=765), in which 112 men had type 2 diabetes. The inflammatory indicators were increased in men with diabetes (urinary 15-keto-dihydro-PGF2alpha, P