Magnesemia in COVID-19 ICU patients: the relationship between serum magnesium level and mortality

Objective: This study aimed to investigate the relationship between serum magnesium (Mg) levels at the time of admission and survival in COVID-19 patients followed in the intensive care unit (ICU).

Methods: In total, 461 patients over the age of 18 diagnosed with the COVID-19, followed in the COVID-19 ICU of our hospital, were included. Patients whose files could not be accessed were excluded. Data on patients' demographics, clinical features, and laboratory data were compared according to the Mg levels measured during their admission to the ICU. The patients were divided into five groups according to their Mg level: Group 1 (<1.8 mg/dL), Group 2 (1.8-<2 mg/dL), Group 3 (2-<2.2 mg/dL), Group 4 (2.2-<2.4 mg/dL), and Group 5 (>2.4 mg/dL).

Results: For patients with Mg value of <2 mg/dL, the proportion of males to females was roughly equal, however, the proportion of males was higher in other groups (p = 0.004). Overall, hypertension was the most common comorbid disease in patients, followed by diabetes mellitus in 32.1%. The latter was observed more frequently in Group 1 (<1.8 mg/dL) compared to the other groups (51.3%, p = 0.008). No significant difference was determined between the groups regarding laboratory values and treatments administered. Requirement of mechanical ventilation was significantly higher in Groups 1 (<1.8 mg/dL) and 5 (>2.4 mg/dL) than in other groups (p = 0.008). However, although mortality was also high in these groups, the difference was not statistically significant (p = 0.067).

Conclusion: A correlation between serum Mg levels and mortality was not observed, but mortality and the need for mechanical ventilation were higher in groups with Mg levels <1.8 mg/dL and >2.4 mg/dL compared to other groups. We believe that it is critical to measure serum Mg levels while supporting COVID-19 patients with Mg in the ICU.