Diabetes and risk of anastomotic leakage after gastrointestinal surgery

Anastomotic leakage (AL) is one of the most common and lethal complications in gastrointestinal surgery. However, the relationship between AL risk and diabetes mellitus (DM) remains ambiguous. This meta-analysis was to evaluate the association between DM and AL risk in patients after gastrointestinal resection.Odds ratios (OR) estimate with their corresponding 95% confidence intervals (CIs) were combined and weighted to produce pooled OR using the fixed-effects model. Relative risks were calculated in subgroup analysis of prospective studies. We calculated publication bias by Begg rank correlation test and Egger linear regression test.DM was significantly and independently associated with an increased risk of AL morbidity in colorectal patients, 1.661 times in total patients (95% CIs = 1.266-2.178), 1.995 times in a subgroup of case-control studies, 1.581 times in cohort investigations, 1.688 times in retrospective trials, and 1.562 times in prospective designs. After adjusting for the factor of obesity and/or body mass index in the subgroup analyses of colorectal surgery, DM patients without obesity experienced a significantly increased risk of AL (OR = 1.572, 95% CIs = 1.112-2.222). Furthermore, when obesity had not been adjusted, DM patients endured a dramatical increase of AL incidence (OR = 1.812, 95% CIs = 1.171-2.804). Perforation incidence after gastric resection showed borderline association with DM (OR = 2.170, 95% CIs = 0.956-4.926).The present meta-analysis provides strong evidence for the first time that DM is significantly and independently associated with an increased risk of AL mortality in colorectal surgery.