Does Hyponatremia Affect the Short-Term Outcomes of Colorectal Cancer Surgery: A Propensity Score Matching Analysis

Abstract

Purpose. The purpose of the current study is to analyze whether preoperative hyponatremia affected the short-term outcomes of colorectal cancer (CRC) surgery. Methods. This retrospective study was conducted in a single clinical center where we enrolled patients who underwent primary CRC surgery from January 2011 to December 2021. The short-term outcomes were compared between the hyponatremia group and the normal sodium group using propensity score matching (PSM) analysis. Results. A total of 6730 cases of patients who received CRC surgery were finally included in this study. There were 184 patients in the hyponatremia group and 6546 patients in the normal sodium group. After 1 : 1 ratio PSM, 184 patients in the normal sodium group were matched to 184 patients in the hyponatremia group. No significant difference was found in baseline information after PSM ( $P>0.05$ ). After PSM, the hyponatremia group had higher patients with overall complications ( $P=0.013$ ). Univariate and multivariate logistic regression analysis were conducted to find predictors of complications, and we found that older age ( $P=0.032$ , $\text{OR}=1.023$ , $95\%\text{CI}=1.002-1.044$ ), open surgery (P =0.001, $\text{OR}=2.300$ , $95\%\text{CI}=1.420-3.727$ ), blood loss ( $P=0.015$ , $\text{OR}=1.002$ , $95\%\text{CI}=1.000-1.003$ ), and hyponatremia ( $P=0.012$ , $\text{OR}=1.856$ , $95\%\text{CI}=1.148-3.001$ ) were independent predictors of patients with overall complications. Conclusion. Hyponatremia was an independent predictor of patients with overall complications after CRC surgery, therefore, the adequate preparation of the patients for surgery remained fundamental.