The Predictive Value of Time-Averaged Cumulative Magnesium on Survival of Maintenance Hemodialysis Patients

Magnesium (Mg) plays a critical role in determining survival outcomes for maintenance hemodialysis (MHD) patients. This study aimed to investigate the prognostic value of time-averaged cumulative magnesium (TAC-Mg) in this population.

The present study retrospectively analyzed 279 eligible MHD patients enrolled in November 2018, collecting demographic data, quarterly predialysis biochemical profiles, and TAC-Mg calculated via standardized formulas. After 4 years of follow-up, multiple statistical approaches were employed to assess predictive value of TAC-Mg for all-cause mortality in MHD patients.

Compared to the high TAC-Mg group, patients in the low TAC-Mg group were older, had a higher proportion of smokers, and exhibited poorer nutritional status. Kaplan-Meier analysis revealed that MHD patients in the low TAC-Mg group had a 4.855-fold higher risk of all-cause mortality compared to the high TAC-Mg group. Multivariable linear regression and Cox proportional hazards models demonstrated that TAC-Mg independently predicted all-cause mortality outcomes after adjusting for age, nutritional status, serum potassium, and chronic kidney disease mineral bone disorder markers (per 1-standard deviation increase: hazard ratio = 0.636, [95% confidence interval 0.470-0.861], P = .003). Receiver Operating Characteristic Curve (ROC) curve analysis further confirmed the superior predictive value of TAC-Mg over single-point baseline serum Mg levels for all-cause mortality risk in this population. The cutoff value of TAC-Mg to predict all-cause mortality risk was ≤1.07 mmol/L.

Low TAC-Mg independently predicts all-cause mortality risk in MHD patients. The prognostic value of TAC-Mg may surpass that of single-point baseline Mg measurements. TAC-Mg ≤1.07 mmol/L may be a clinical warning threshold for increased all-cause mortality risk in this population.