Association between serum calcium levels and in-hospital mortality in sepsis: A retrospective cohort study

• Published in: Heliyon 2024-08, Vol.10 (15), p.e34702, Article e34702
• Main Authors: Wang, Hui, Sun, Hui, Sun, Jinping
• Format: Article
• Language: English
• Subjects: adults; blood serum; calcium; cohort studies; hospitals; In-hospital mortality; MIMIC-; mortality; patients; Sepsis; Serum calcium
• ISSN: 2405-8440; 2405-8440
• DOI: 10.1016/j.heliyon.2024.e34702

This study examines serum calcium levels and in-hospital mortality in patients with sepsis, a subject with contradictory findings in the existing literature. This retrospective cohort study utilized data from the MIMIC-IV database, focusing on adult patients diagnosed with sepsis between 2008 and 2019. The serum calcium levels were taken as the highest value within the first 24 h of Intensive Care Unit (ICU) admission. We performed Cox proportional hazards regression analyses in multivariable-adjusted models to investigate the association between serum calcium levels and in-hospital mortality. Restricted cubic spline functions were used to assess the nonlinear relationship, and threshold effect analysis was conducted to identify potential inflection points. A total of 18,546 patients with sepsis were included in the study, and an in-hospital mortality rate of 16.9 % (3,126 out of 18,546) was obtained. Furthermore, a U-shaped relationship was observed between serum calcium concentrations and in-hospital mortality, with the lowest point at approximately 8.23 mg/dL. Hazard ratios were calculated as 0.75 (95 % CI: 0.67–0.85, P