We collected general data consisted of age, sex, body mass index (BMI), place of residence, educational level, diabetes mellitus status and duration of HD; as well as clinical, biochemical indicators, including serum calcium (Ca), serum phosphorus (P), serum albumin (ALB), haemoglobin (Hb), serum intact parathyroid hormone (iPTH), pre-dialysis serum urea nitrogen (BUN), normalized protein catabolic rate (nPCR), urea nitrogen clearance index (KT/V), ferritin (FER) and pre-dialysis serum creatinine (sCR). This evidence concerns the gene GSTM1 and diabetes mellitus.