Systematic Review And Meta-analysis Of The Relationship Between Serum Magnesium And Mortality In Hemodialysis Patients

Background: Recent studies have shown an association between serum magnesium and increased risk of mortality in hemodialysis patients;however,the estimates vary widely and the results are inconsistent.It is necessary to elucidate the relative risk of abnormal serum magnesium to mortality in hemodialysis patients.Methods: PubMed,Embase,Web of Science,and Cochrane Library(from inception to April 29,2018)were systematically searched for cohort studies assessing the association between serum magnesium and mortality in hemodialysis patients.We calculated the pooled hazard ratios(HRs)with 95% confidence intervals(CI)of all-cause and cardiovascular mortality using random effects models.Subgroup analyses were conducted to explore the sources of heterogeneity.Results: The search identified 1139 potentially eligible records and 9 studies(n=177329)were included.Our meta-analysis showed that in studies treating magnesium level as categorical variables,lower serum magnesium significantly increased the risk of all-cause mortality(HR=1.36,95%CI 1.16-1.60,n=176274),but higher serum magnesium was not associated with increased risk of all-cause mortality(HR=0.97,95%CI 0.67-1.41,n=164274).In studies treating magnesium level as continuous variable,Serum magnesium was not associated with increased risk of all-cause mortality(HR=0.78,95%CI 0.57-1.09,n=1045)or cardiovascular mortality(HR=0.81,95%CI 0.58-1.12,n=1045).Subgroup analysis showed that different regions,age and study type may be the sources of heterogeneity.Conclusion: Lower serum magnesium may be a prognostic marker of all-cause mortality in hemodialysis patients.More attention should be paid to serum magnesium level in hemodialysis patients.