Abstract: Objective  To explore the relationship between serum magnesium (Mg) and all-cause death in maintenance hemodialysis (MHD) patients.  Methods  We reviewed the general condition, biochemical indexes and prognosis of MHD patients treated in the Hemodialysis Center of Beijing Civil Aviation General Hospital from January 2018 to December 2023.  Results A total of 415 patients were enrolled, including 156 females (37.6%), with a mean age of 65.64±13.46 years and a median dialysis age of 69.0 (33.0, 129.0) months. The observation period was 48.0 (27.0, 69.0) months, during which a total of 156 died. Kaplan-Meier curve analysis revealed a significantly lower survival rate in the low Mg group (≤1.04mmol/L) than in the high Mg group (＞1.04mmol/L) (Log-rank, χ2=6.767, P=0.009). Univariate Cox regression analysis revealed that serum magnesium was a protective effect on all-cause death in MHD patients (HR=0.903, 95% CI: 0.823～0.991, P=0.032). However, multivariate regression analysis showed that serum magnesium had no independent protective effect on all-cause death in MHD patients (HR=0.952, 95% CI: 0.964～1.019, P=0.120); albumin (HR=0.793, 95% CI: 0.725～0.868, P＜0.001) was identified as an independent protective factor, while advanced age (HR=1.028, 95% CI:1.012～1.045, P=0.001), diabetes mellitus (HR=1.249, 95% CI: 1.109～1.792, P=0.022), and cardiovascular and cerebrovascular disease (HR=1.654, 95% CI: 1.105～2.476, P=0.015) were associated with a higher risk of mortality. Kaplan-Meier curve analysis revealed that the double negative group (Mg＞1.04mmol/L and albumin≥38g/L), single positive group (Mg ≤1.04mmol/L or albumin ＜38g/L) and the double positive group (Mg ≤1.04mmol/L and albumin＜38g/L) showed a successively decreased survival rate (Log-rank, χ2=48.746, P＜0.001). Compared with the single positive group, the double positive group had a higher risk of death (HR=1.150, 95% CI: 1.089～1.683, P=0.046), and the double negative group had a significantly lower risk of death (HR=0.537, 95% CI: 0.316～0.912, P=0.021).  Conclusion Hypomagnesemia is not an independent risk factor for all-cause death in MHD patients, but hypomagnesemia combined with hypoalbuminemia increase the risk of all-cause death in MHD patients.

Key words: Maintenance hemodialysis, Serum magnesium, Inflammation, Death