After LASSO regression selection (Figure 3), the following 16 variables remained significant predictors of all-cause mortality, including diabetes mellitus, phosphate binders, DBP2h, albumin, phosphorus, ΔaSKNA240, VLF, LF/HF, rMSSD240, ULF240, VLF240, LF/HF240, ΔVLF240, ΔApEn240, ΔNnmean30, ΔApEn30. Here, ALB is linked to diabetes mellitus.