Impact of diabetes mellitus on long-term prognosis after gastrectomy for advanced gastric cancer: a propensity score matching analysis

Purpose We investigated the long-term prognostic impact of diabetes mellitus (DM) after gastrectomy for advanced gastric cancer. Methods This was a retrospective cohort study of consecutive patients who underwent gastrectomy for primary p-T2 or more advanced-stage gastric cancer, between April, 2008 and June, 2018. The overall survival (OS) of patients with DM and those without DM were compared using Kaplan-Meier survival analysis after adjusting for group differences using propensity score matching (PSM). Results Among the 512 patients who met the eligibility criteria, 92 (18.0%) had DM and 420 (82.0%) did not. After PSM, the subjects of this analysis were 72 patients in the DM group and 216 patients in the non-DM. OS was significantly worse in the DM group than in the non-DM group (P = 0.037). Multivariate analysis revealed that a low skeletal muscle mass index was a significant independent prognostic factor for OS in the patients with DM (hazard ratio, 2.284; 95% confidence interval, 1.005-5.189; P = 0.048). Conclusions DM in patients with advanced gastric cancer is associated with poor OS. A low skeletal muscle mass in patients with DM is a particularly poor prognostic factor for OS after surgery for gastric cancer.