Magnesium deficiency may increase the risks for cardiovascular and all-cause mortality in patients with chronic kidney disease (CKD) and end-stage renal disease (ESRD).
Investigators led by Jinghong Zhao, MD, PhD, of the Third Military Medical University in China, confirmed the associations in a systematic review and meta-analysis of 20 studies including 200,934 patients from Asia, Europe, or the United States.
In multivariate analyses, CKD and ESRD patients with hypomagnesemia had a significant 32% higher risk for all-cause mortality than those with normal or elevated magnesium levels, according to results published in the Journal of Nephrology. Patients on hemodialysis (HD) had a 29% higher risk.
In contrast, hypermagnesemia was inversely associated with all-cause mortality in patients with CKD and ESRD. Each 1-unit increase in serum magnesium was associated with a significant 14% decreased risk for death, in adjusted analyses. Hypermagnesemia was associated with a significant 29% decreased risk for cardiovascular mortality compared with normal or elevated serum magnesium levels.
Among a number of possible mechanisms, low magnesium may contribute to inflammation and immune deficiency, the study authors speculated.
“Evidence linking magnesium and mortality in CKD and dialysis patients suggests that nephrologists should carefully monitor serum magnesium in patients,” Dr Zhao and his coauthors wrote. “Maintaining a high magnesium level may be advantageous to improve the cardiovascular prognosis of hemodialysis patients with hyperphosphatemia.
“Nevertheless, it is unclear if patients can benefit from magnesium supplementation, and additional prospective studies are needed to prove the hypothesis.”
Magnesium categories differed across studies, which is a limitation of the meta-analysis.
Xiong J, He T, Wang M, Nie L. Serum magnesium, mortality, and cardiovascular disease in chronic kidney disease and end-stage renal disease patients: a systematic review and meta-analysis. J Nephrol. DOI:10.1007/s40620-019-00601-6