Abstract
BACKGROUND: Magnesium deficiency represents a prevalent electrolyte imbalance that notably heightens the risk of adverse cardiovascular incidents among individuals with heart failure. Research indicates that magnesium supplementation can diminish the frequency of negative events linked to hypomagnesemia in heart failure patients, while also enhancing the outcomes for critically ill individuals. Nevertheless, there remains a scarcity of studies investigating the effects of intravenous magnesium supplementation on mortality risk in those suffering from acute heart failure. This study aimed to explore the relationship between the administration of intravenous magnesium sulfate and the overall mortality risk in patients with acute heart failure who are admitted to intensive care units. METHODS: This retrospective cohort study employed the Medical Information Mart for Intensive Care IV (MIMIC-IV) database (version 3.1), which encompasses the baseline clinical data of 10,031 patients diagnosed with acute heart failure. Propensity score matching and multivariate Cox regression analysis were utilized to assess the effects of intravenous magnesium sulfate on 28-day all-cause mortality. The evaluation of unmeasured confounding variables was undertaken through E-value calculations, while subgroup analyses were performed to ascertain the robustness of the results. RESULTS: A total of 10,031 patients participated in the study, with 6240 belonging to the propensity-score matched group, which included 3120 subjects who received intravenous magnesium sulfate and 3120 who did not. The entire cohort consisted of 10,031 individuals, whereas the matched cohort specifically comprised 6240 patients. Within the matched group, the rates of 28-day all-cause mortality were observed to be 13.2% (413/3120) for those administered intravenous magnesium sulfate, compared to 15.8% (493/3120) for the control group. Administration of intravenous magnesium sulfate correlated with a significantly reduced risk of 28-day all-cause mortality (hazard ratio (HR), 0.81; 95% confidence interval (CI), 0.71-0.93; p = 0.004). A sensitivity analysis conducted on the entire cohort corroborated this association (HR, 0.77; 95% CI, 0.69-0.87; p < 0.001). Additional subgroup analyses and E-value assessments reinforced the relevance of these results. Furthermore, intravenous magnesium sulfate was linked to reduced all-cause mortality at both 90 and 365 days. CONCLUSIONS: Intravenous magnesium sulfate appears to decrease all-cause mortality in patients with acute heart failure, while further prospective studies are warranted to validate these results.