Association of magnesium sulphate use with mortality in patients with acute respiratory distress syndrome: a retrospective propensity score-matched cohort study

Few reports have documented magnesium supplementation effects on mortality rates of patients with acute respiratory distress syndrome (ARDS). This study investigated the potential correlation between magnesium sulphate use and mortality in patients with ARDS. Records of critically ill adult patients with ARDS from the Medical Information Mart in Intensive Care IV database were analysed. The exposure was magnesium sulphate administration during intensive care unit (ICU) stay. The primary outcome was in-hospital mortality. A 1:1 ratio propensity score matching (PSM) was performed; multivariable analyses were conducted to account for potential confounders. The study cohort comprised 5,499 patients before PSM and 1,282 patients after PSM. For PSM, the in-hospital mortality rates were 32.29% (207/641) and 37.44% (240/641) in the magnesium sulphate use and no-use groups, respectively. Magnesium sulphate use was associated with lower in-hospital mortality (hazard ratio [HR], 0.71; 95% confidence interval [CI], 0.59-0.85; P < 0.001) and lower ICU 30-day mortality (HR, 0.75; 95% CI, 0.62-0.90; P = 0.002). The entire cohort had lower in-hospital mortality in the multivariable (HR, 0.67; 95% CI, 0.57-0.78; P < 0.001) and univariable (HR, 0.41; 95% CI, 0.36-0.47; P < 0.001) sensitivity analyses. Magnesium sulphate use was associated with a lower in-hospital mortality rate for patients with ARDS.