Vitamin D supplementation is associated with improved outcomes in critically ill patients with acute pancreatitis in the intensive care unit: a retrospective analysis based on the MIMIC-IV database

Background Acute pancreatitis (AP) is a common gastrointestinal emergency, and its progression to severe forms in the intensive care unit (ICU) is associated with high mortality. Vitamin D, beyond its classical role in bone metabolism, possesses significant immunomodulatory and anti-inflammatory properties. Although numerous studies have found that vitamin D supplementation may improve prognoses in critically ill patients, no research to date has demonstrated a benefit in patients with AP. Therefore, this study examined the association between vitamin D supplementation and mortality in ICU patients with AP. Methods This retrospective cohort study utilized data from the Medical Information Mart for Intensive Care-IV (MIMIC-IV) database. Adult ICU patients diagnosed with AP were included. Patients were categorized into vitamin D and non-vitamin D groups based on supplementation during their ICU stay. The primary and secondary outcomes were 28-day and 90-day all-cause mortality, respectively. Associations were assessed using Kaplan-Meier (KM) survival curves and multivariable Cox proportional-hazards models, with adjustments for relevant demographic, clinical, and laboratory confounders. Results The study finally included 1068 patients with AP, comprising 131 and 937 in the vitamin D and non-vitamin D groups, respectively. The KM survival curves indicated that the survival probability differed significantly between the two groups. Following multivariate COX regression, which was adjusted for confounding factors, the hazard ratio (95% confidence interval) values for 28-day and 90-day mortality in the vitamin D group were 0.29 (0.15, 0.55) and 0.33 (0.2, 0.54), respectively. Conclusion In this retrospective analysis, vitamin D supplementation was independently associated with a significant reduction in 28-day and 90-day mortality among ICU patients with AP. Given the favourable safety profile and low cost of vitamin D, these findings warrant confirmation in large-scale, prospective randomised controlled trials to establish a potential causal relationship and guide clinical practice.