Association between serum osmolality and 30-day all-cause mortality in patients with acute pancreatitis: A retrospective analysis of the MIMIC-IV database.

BACKGROUND

Acute pancreatitis (AP) is a prevalent inflammatory condition that can result in multiple organ failure. Previous research has established a correlation between serum osmolality and outcomes in critically ill patients. However, the specific relationship between serum osmolality and AP remains ambiguous.

METHODS

Our retrospective cohort study employed data from the Medical Information Mart for Intensive Care IV (MIMIC-IV) database. We utilized multivariable Cox regression analysis, Kaplan-Meier survival curves, restricted cubic spline (RCS) curves, and threshold effect analysis to evaluate the impact of serum osmolality on mortality. Subgroup analyses were performed, and interactions were assessed. Additionally, sensitivity analysis was conducted by excluding samples with missing data.

RESULTS

The final cohort comprised 914 patients diagnosed with AP (mean age, 58.7 ± 17.5 years; 57.3 % male), with a 30-day mortality rate of 15.3 %. Elevated serum osmolality emerged as an independent prognostic factor for mortality (hazard ratio [HR], 1.11; 95 % confidence interval [CI], 1.06-1.16; P < 0.001). A nonlinear dose-response pattern was demonstrated, with thresholds identified at 298.5 mmol/L based on RCS analysis and threshold effect analysis. Kaplan-Meier analysis revealed patients with high serum osmolality have lower survival rates. Subgroup and sensitivity analyses demonstrate the robustness of the results.

CONCLUSIONS

Serum osmolality demonstrated a nonlinear relationship with 30-day all-cause mortality among AP patients. A significant threshold was observed at 298.5 mmol/L, beyond which elevated serum osmolality was associated with 30-day all-cause mortality.