Elderly age (155.9, 95% CI for regression coefficients: 107.4 to 204.4, p < 0.01), male sex (105.3, 95% CI: 63.4 to 147.3, p < 0.01), diabetes mellitus (108.2, 95% CI: 66.2 to 150.2, p < 0.01), dialysis vintage (102.6, 95% CI: 46.2 to 159.0, p < 0.01), and the percentage of lymphocytes (92.9, 95% CI: 51.4 to 134.4, p < 0.01) were also associated with the anti-S1 IgG titer. This evidence concerns the gene PSMD1 and diabetes mellitus.