The impact of diabetes mellitus on short and long term outcomes in patients with gastric cancer following radical surgery: a retrospective cohort study with propensity score matching.

Background: The objective of this study was to analyze the impact of diabetes mellitus (DM) on short and long term outcomes following radical gastrectomy using propensity score matching (PSM) method, as well as to further investigate the factors influencing patient survival post-radical gastrectomy.

Methods: The patients who underwent radical gastrectomy for gastric cancer (GC) between January 2011 and December 2015 were selected as study population, and PSM procedure was conducted with a matching ratio of 1:3 between the DM and non-DM groups. The short-term recovery and long-term survival outcomes were compared between the DM and non-DM group. Subsequently, univariate and multivariate COX regression analyses were conducted to further explore the factors that influence survival outcomes.

Results: Among the cohort of 2508 GC patients who underwent radical surgery prior to PSM, a total of 295 (11.8%) individuals were diagnosed with DM. After conducting 1:3 PSM, 293 DM patients and 821 control patients were enrolled. The results of comparative analysis revealed that the DM group exhibited a significantly higher rate of overall complications (P < 0.001), grade III-V complications (P = 0.010), and prolonged hospitalization (P = 0.001) compared to the control group. However, no statistical difference was observed in survival outcomes between the two groups. Besides, age > 65years (P < 0.001), BMI < 18.5 kg/m (P = 0.001), tumor size > 5 cm (P < 0.001), higher T (P = 0.012) and N tumor stage (P < 0.001), and the occurrence of severe complications (P = 0.007) were identified as independent risk factors for overall survival (OS).

Conclusions: The presence of combined DM in GC patients can heighten the susceptibility to postoperative complications and protract the duration of postoperative recovery, while exerting no significant impact on OS. This study also explored the predictors for OS, thereby providing valuable guidance for the perioperative management and postoperative monitoring.