Hyponatremia Is Associated with Mortality in Acute Pancreatitis Patients.

Background: Disorders of serum sodium are common among general patients and are associated with poor outcomes. The prognostic value of serum sodium disorders in patients with acute pancreatitis (AP) has not been studied. We conducted this retrospective study to explore the association between serum sodium levels and the outcomes of patients with AP.

Materials And Methods: Patients with AP from the Medical Information Mart for Intensive Care III (MIMIC-III) were screened for this study. The laboratory variables, including serum sodium levels, were obtained by analyzing the first blood sample on the first day after admission. Univariate logistic regression was performed to discover potential factors for mortality of AP. The unadjusted and adjusted association between serum sodium level and mortality of AP was shown by the restricted cubic spline (RCS). The categorical cutoff for the detrimental effect of serum sodium level on the prognosis of AP was also confirmed by stepwise logistic regression after adjusting for con-founding effects of significant factors in the univariate logistic regression.

Results: A total of 869 patients with AP in the MIMIC-III were included with a mortality of 13.1%. Unadjusted logistic regression showed that age (p < 0.001), simplified acute physiological score (SAPS) (p < 0.001), systolic blood pressure (p < 0.001), diastolic blood pressure (p < 0.001), hemoglobin (p = 0.040), serum creatinine (p = 0.046), and serum phosphorus (p < 0.001) were significantly associated with the mortality of AP. The RCS showed that the serum sodium level was negatively and linearly associated with mortality of AP after adjusting for confounding effects of significant factors in the univariate logistic regression. Serum sodium < 133 mmol/L, which indicated hyponatremia, was significantly correlated with a higher mortality risk than serum sodium ≥ 133 mmol/L (p = 0.013).

Conclusions: Hyponatremia is widely developed among patients with AP and correlates with a higher mortality risk of AP. Physicians should pay more attention to managing patients with AP with hyponatremia.