Hypomagnesemia in Burn Patients: Risk Factors and Mortality Outcomes

Background: Magnesium is an intracellular ion critical for cell adhesion, nerve conduction, and cellular metabolism. In critically ill patients, particularly those with burns, hypomagnesemia is a frequent complication, largely due to exudative losses. The impact of hypomagnesemia on clinical outcomes, especially mortality, remains insufficiently studied. Methods: We conducted a retrospective cohort study of patients admitted to the Burn Intensive Care Unit at Sheba Medical Center, Israel, between 2014 and 2025. The study aimed to assess the prevalence and risk factors for hypomagnesemia and its association with short-term mortality in burn patients. Hypomagnesemia was defined as serum magnesium <1.8 mg/dL. A total of 1,119 patients were categorized based on whether they developed hypomagnesemia during hospitalization. Those with hypomagnesemia were further stratified into severe (<1.2 mg/dL) and non-severe (1.2–1.8 mg/dL) groups. Results: Of 1,119 patients, 651 (58%) developed hypomagnesemia, including 606 with non-severe and 45 with severe levels. Compared to normomagnesemic patients, those with hypomagnesemia were more often male, had diabetes, larger burn surface area, AKI, hypokalemia, hypercalcemia, and hypoalbuminemia. They were more frequently intubated and received diuretics, PPIs, laxatives, aminoglycosides, amphotericin B, and zinc. Independent risk factors included diuretic use (OR 3.65, 95% CI 1.82–7.60, p<0.001), laxatives (OR 1.62, p=0.041), AKI (OR 4.75, p=0.016), diabetes (OR 4.42, p=0.002), hypoalbuminemia (OR 0.49, p<0.001), and burn surface area (OR 1.03, p=0.014). Hypomagnesemia was associated with significantly higher mortality at all time points: in-hospital (19.4% vs. 1.5%, p<0.001), 14-day (10.3% vs. 1.1%, p<0.001), and 30-day (15.4% vs. 1.3%, p<0.001). Conclusion: Hypomagnesemia is highly prevalent among burn patients and is independently associated with larger burn area, diuretic and laxative use, acute kidney injury, diabetes, and hypoalbuminemia. It is strongly linked to increased short-term mortality, with the highest mortality observed in patients with severe hypomagnesemia. These findings highlight the need for routine monitoring and clinical awareness of magnesium disturbances in this high-risk population. Prospective studies are warranted to evaluate whether early identification and correction of hypomagnesemia can improve clinical outcomes.