Magnesium status and clinical outcomes in kidney transplant recipients: Systematic review and meta-analysis

Natalia  Stepanova; Svitlana  Fomina; Mykola  Kolesnyk

doi:10.31450/ukrjnd.3(87).2025.04

Natalia Stepanova State Institution “O.O. Shalimov National Scientific Center of Surgery and Transplantology of the National Academy of Medical Science of Ukraine,” Kyiv, Ukraine https://orcid.org/0000-0002-1070-3602
Svitlana Fomina State Institution “O.O. Shalimov National Scientific Center of Surgery and Transplantology of the National Academy of Medical Science of Ukraine,” Kyiv, Ukraine https://orcid.org/0000-0001-7483-9712
Mykola Kolesnyk State Institution “O.O. Shalimov National Scientific Center of Surgery and Transplantology of the National Academy of Medical Science of Ukraine,” Kyiv, Ukraine https://orcid.org/0000-0001-6658-3729

DOI: https://doi.org/10.31450/ukrjnd.3(87).2025.04

Keywords: kidney transplantation, magnesium, all-cause mortality, cardiovascular outcomes, graft survival, infections, systematic review, meta-analysis.

Abstract

Kidney transplant recipients (KTRs) remain at risk for metabolic, cardiovascular, and infectious complications. Magnesium abnormalities are common but their prognostic significance remains unclear.

Objectives. To systematically review and meta-analyze the association between serum magnesium status and clinical outcomes in KTRs.

Methods. We searched PubMed, Embase, Web of Science, Cochrane Library, and ClinicalTrials.gov (by May 31, 2025). Eligible studies were observational cohorts in adult KTRs reporting outcomes by magnesium categories. The primary outcome was all-cause mortality; secondary outcomes were cardiovascular events, graft outcomes, and infections. Data were synthesized using random-effects meta-analysis where ≥3 studies were available, complemented by Bayesian analysis. Risk of bias was assessed with the Newcastle–Ottawa Scale (NOS), and certainty of evidence was graded using GRADE. The protocol was registered with the International Prospective Register of Systematic Reviews (PROSPERO, ID: CRD420251055485).

Results. Eight studies (n=7,026 KTRs) met the inclusion criteria. Five studies assessed all-cause mortality, and four provided adjusted estimates for pooling. Higher/normal magnesium (≥1.7–1.8 mg/dL) vs. lower was associated with increased mortality (HR 1.17, 95% CI 1.06–1.29; I²=59.5%). Sensitivity analysis excluding one null study yielded HR 1.18 (95% CI 1.03–1.34). Bayesian modeling produced consistent but uncertain estimates (posterior HR 1.22, 95% CrI 0.94–1.68; BF₁₀=0.88). Evidence for cardiovascular, graft, and infection outcomes was inconsistent and heterogeneous, precluding pooling. Certainty of evidence was low for the all-cause mortality outcome and very low for secondary outcomes.

Conclusions. Current evidence from a small number of heterogeneous observational studies suggests that higher/normal serum magnesium status may be associated with a modest increase in all-cause mortality among KTRs. However, the certainty of evidence is low, and associations with cardiovascular, graft, and infection outcomes remain inconclusive. Prospective multicenter cohorts and interventional trials are needed to determine whether magnesium status is a causal and modifiable factor and to define the optimal post-transplant magnesium range.