Hypomagnesemia Is Associated with the Acute Kidney Injury in Traumatic Brain Injury Patients: A Pilot Study

Abstract

Background: Acute kidney injury (AKI) commonly develops among traumatic brain injury (TBI) patients and causes poorer outcomes. We perform this study to explore the relationship between serum magnesium and the risk of AKI among TBI. Methods: TBI patients recorded in the Medical Information Mart for Intensive Care-III database were eligible for this research. The restricted cubic spline (RCS) was utilized to fit the correlation between serum magnesium level and the AKI. Univariate and subsequent multivariate logistic regression analysis were utilized to explore risk factors of AKI and confirmed the correlation between serum magnesium and AKI. Results: The incidence of AKI in included TBI was 21.0%. The RCS showed that the correlation between magnesium level and risk of AKI was U-shaped. Compared with patients whose magnesium level was between 1.5 and 2.0 mg/dL, those with a magnesium level of <1.5 mg/dL or >2.0 mg/dL had a higher incidence of AKI. Multivariate logistic regression confirmed age, chronic renal disease, ISS, serum creatinine, vasopressor, mechanical ventilation, and serum magnesium <1.5 mg/dL were independently related with the AKI in TBI. Conclusion: Abnormal low serum magnesium level is correlated with AKI development in TBI patients. Physicians should pay attention on renal function of TBI patients especially those with hypomagnesemia.

Association between Serum Magnesium Levels and Risk of Acute Kidney Injury in Patients with Traumatic Brain Injury: A Retrospective Cohort Study from the MIMIC-IV Database

“…Our results demonstrated that both lower serum magnesium levels (≤1.7 mg/dL) at admission and greater changes in magnesium levels during hospitalization (CV >10%) were linked to an increased risk of AKI. Recently, Liu et al [15] conducted a study to explore the factors associated with the risk of AKI in patients with TBI and showed that hypomagnesemia was associated with a higher risk of AKI. However, their study did not analyze the effect of magnesium changes on AKI risk nor did it analyze the effect of magnesium on AKI risk in different patients (e.g., GCS scores).…”

“…Several possible mechanisms for the effect of serum magnesium levels on AKI risk have been proposed. Magnesium is an important modulator of vascular tone and enhances renal vasodilatation by releasing endogenous vasodilators such as nitric oxide, adenosine, and prostaglandins, as well as by forming competition with calcium ions (Ca + ) [15,30]. Lower magnesium levels are associated with inflammation, as magnesium deficiency opens calcium channels, upregulates pro-inflammatory cytokines, and activates nuclear factor-κB, leading to inflammation [31].…”

“…Studies have shown that lower levels of serum magnesium at admission are significantly related to an increased risk of AKI in patients with acute pancreatitis, cardiac surgery, and cancer [12][13][14]. Recently, Liu et al [15] found that hypomagnesemia was associated with a higher risk of AKI in patients with TBI. However, their study did not analyze the effect of magnesium changes during hospitalization on AKI risk.…”