Serum Magnesium Levels and Mortality in Japanese Maintenance Hemodialysis Patients.

BACKGROUND/AIMS: Although hypomagnesemia was found to be a risk for cardiovascular diseases in the general population, the relationship between serum magnesium (Mg) levels and prognosis of patients on maintenance hemodialysis (MHD) has not been extensively studied. This study sought to determine the relationship of serum Mg levels with aortic arch calcification (AoAC) and mortality in Japanese MHD patients.

METHODS: We measured serum Mg levels in a cohort of 392 patients on MHD, classified the patients into 3 groups according to these levels, and followed their course for 4 years. AoAC was assessed using chest-X-rays.

RESULTS: During follow-up, there were 117 deaths. Kaplan-Meier analyses showed that the high serum Mg group tended to have better survival rates than the low and middle serum Mg groups but this did not reach statistical significance. We also found that patients in the high serum Mg group had better nutritional status associated with higher serum albumin, triglyceride, and phosphate levels and had a significantly lower serum C-reactive protein level. In total, 83 patients (59.3%) in the high serum Mg group had been prescribed Mg oxide (MgO).

CONCLUSIONS: Hypermagnesemia tended to be associated with better survival and a higher prescription rate of MgO. Interventional studies are needed to clarify whether Mg supplementation is beneficial for improving patient prognosis.