In the univariate analysis, old age, male sex, lower BMI, presence of comorbidities (diabetes mellitus, hypertension, ischemic heart disease, heart failure, cerebrovascular accident, and atrial fibrillation), lower plasma Hb, serum albumin, calcium, and phosphorus levels, and lower single-pool Kt/V were associated with a higher mortality risk (Supplementary Table 2). This evidence concerns the gene GSTM1 and diabetes mellitus.