A study of 118 patients with CKD showed that estimated glomerular filtration (eGFR) and levels of HbA1c or plasma glucose were significantly, independently, and positively associated with plasma XOR activity after adjusting for several confounders; in addition, plasma XOR activity was significantly higher in diabetic CKD patients than in those without diabetes, and the relationship between glycemic control and plasma XOR activity was significant even in CKD patients without uric acid-lowering drug treatment. Here, XDH is linked to diabetes mellitus.