Lack of clinical benefit from preoperative short-term parenteral nutrition on the clinical prognosis of patients treated with radical gastrectomy for gastric cancer: a two-center retrospective study based on propensity score matching analysis.

ABSTRACT

Background: Preoperative nutritional support studies for patients undergoing gastrointestinal (GI) surgery mostly focused on enteral nutrition (EN) or long-term (≥7 days) parenteral nutrition (PN). Some studies also found that preoperative short-term PN could improve the postoperative short-term nutritional status of tumor patients. But whether short-term PN support (1-6 days) before surgery can improve the prognosis of patients undergoing surgery for gastric cancer (GC) remains unclear. Therefore, we focused on assessing the effect of preoperative short-term PN on the outcomes of patients undergoing radical surgery for GC. Methods: A retrospective analysis of 1,155 patients who underwent radical gastrectomy for GC between July 2014 and February 2019 was conducted. According to whether patients received short-term (1-6 days) PN support before surgery, patients were divided into non-PN group and PN group. After 11 propensity score matching (PSM), two groups of patients with similar baseline clinical characteristics were obtained. The incidence of various complications and overall survival (OS) rate were compared between the two groups, and logistic regression analysis for complications, Cox regression analysis for OS, and subgroup analysis were performed. Results: Each group had 478 patients after PSM, and the clinical characteristics were balanced. There were no significant differences in overall postoperative complications (pre-PSM P=0.495; post-PSM P>0.99), postoperative length of stay (LOS; pre-PSM P=0.092; post-PSM P=0.460), or readmission rate within 30 days (pre-PSM P=0.496; post-PSM P=0.793) between the two groups before and after PSM. The OS of PN group before matching was lower than that of non-PN group (P=0.023), but this difference was not significant after matching (P=0.950), but the PN group's hospitalization expenses were substantially greater than those of the control group (post-PSM P<0.001). Preoperative short-term PN support was not an independent factor in the incidence of postoperative complications (P>0.99) and OS (P=0.949). Subgroup analyses failed to identify those patients who might benefit from preoperative short-term PN support. Conclusions: Preoperative short-term PN support may have no significant benefit on short-term postoperative complications or the long-term OS of patients with GC but increase hospitalization costs. It thus should not be the first choice of treatment for these patients.