Electrolyte abnormalities in hospitalized COVID-19 patients at tertiary referral centers in Tehran: Hypermagnesemia as a marker of fatality: A retrospective cross-sectional study.

Background and Aims: To evaluate biochemical abnormalities and their association with the outcome of hospitalized coronavirus disease 2019 (COVID-19) patients at a tertiary referral center in Iran. Methods: This retrospective study was conducted on COVID-19 patients who were admitted at tertiary referral centers in Tehran, Iran, from March 2021 to 2022. Demographic and biochemical laboratory data of the patients including blood sodium, potassium, calcium, and magnesium were collected from patient treatment sheets of severe COVID-19 patients admitted to a different ward of the hospital. A logistic regression model was fitted to identify the associated parameters with mortality. Results: Four hundred and ninety-nine patients with COVID-19, including 287 males (57.5%), who had a mean age of 58.95 ± 16.60 years, were enrolled. Thirty-eight patients (7.62%) died during hospitalization. The factors we found to be independently associated with an increased risk of in-hospital death were having comorbidity (mortality of 94.7%, vs. 61% among those without comorbidity; odds ratio, 17.71; 95% confidence interval [CI], 3.81-82.37), hypermagnesemia (34.2%, vs. 26.2% among those with normal magnesium; odds ratio, 9.71; 95% CI, 2.958-31.91), and having a male gender (34.2%, vs. 26.2% among those were female; odds ratio, 9.71; 95% CI, 2.958-31.91). Conclusions: Hypermagnesemia, having a male gender, and the existence of comorbidity in patients with COVID-19 is associated with an increase in mortality. Further studies on the pathogenic mechanisms and therapeutic implications need to be done.