Abstract
BACKGROUND: Diabetes mellitus has been commonly associated with poor surgical outcomes. The aim of this meta-analysis was to assess the impact of diabetes on postoperative complications following colorectal surgery. METHODS: Medline, Embase and China National Knowledge Infrastructure electronic databases were reviewed from inception until May 9th 2020. Meta-analysis of proportions and comparative meta-analysis were conducted. Studies that involved patients with diabetes mellitus having colorectal surgery, with the inclusion of patients without a history of diabetes as a control, were selected. The outcomes measured were postoperative complications. RESULTS: Fifty-five studies with a total of 666,886 patients comprising 93,173 patients with diabetes and 573,713 patients without diabetes were included. Anastomotic leak (OR 2.407; 95% CI 1.837-3.155; p < 0.001), surgical site infections (OR 1.979; 95% CI 1.636-2.394; p < 0.001), urinary complications (OR 1.687; 95% CI 1.210-2.353; p = 0.002), and hospital readmissions (OR 1.406; 95% CI 1.349-1.466; p < 0.001) were found to be significantly higher amongst patients with diabetes following colorectal surgery. The incidence of septicemia, intra-abdominal infections, mechanical failure of wound healing comprising wound dehiscence and disruption, pulmonary complications, reoperation, and 30-day mortality were not significantly increased. CONCLUSIONS: This meta-analysis and systematic review found a higher incidence of postoperative complications including anastomotic leaks and a higher re-admission rate. Risk profiling for diabetes prior to surgery and perioperative optimization for patients with diabetes is critical to improve surgical outcomes.