GNRI levels were found to have a stable effect on outcome events in the subgroup analysis, and this effect was not influenced by covariates (gender, age, diabetes, CKD, MI, COPD, NYHA classification, CCI score, diuretics, creatinine, uric acid, potassium, sodium, hemoglobin, lactate, NT-proBNP, and diuretics) (Figure 3). Here, NPPB is linked to chronic kidney disease.