More than 90% of type II diabetics have obesity, and over 85% of diabetic patients who undergo bariatric surgery will see improvement or resolution of diabetes. However, diabetes (DM) is a known risk factor for surgical complications. It is unclear whether tight preoperative glycemic control confers a perioperative benefit upon this complex patient population.


From the 2017 MBSAQIP database, we identified patients with DM who underwent weight metabolic and bariatric surgery (MBS). An unmatched and propensity-matched analysis, as well as multivariate logistic regression were performed to assess thirty-day perioperative outcomes between patients with poor (HA1c > 7) compared to good glycemic control (HA1c ≤


Of 20,287 diabetic patients, 10,342 (50.97%) met a target HA1C of ≤ 7.Patients with poor glycemic control had higher rates of postoperative infection (2.42% vs. 1.8%, RR=1.35, p=0.002), readmission (4.99% vs. 4.05%, RR=1.23, p=0.001), unplanned ICU transfer(1.32% vs. 0.92%, RR=1.43, p=0.007) and overall morbidity (6.65% vs. 5.53%, RR=1.20, p=0.001.) In matched analysis of 17,596 patients controlling for BMI, operation type, approach, and all other major comorbidities, the findings of poorer infectious and general outcomes were preserved in patients with poor glycemic control. On multivariate analysis, poor glycemic control was an independent risk factor for morbidity (b=1.166, p=0.010).


In diabetic patients, poor glycemic control increases the risk of 30-day adverse outcomes following MBS, and this risk is independent of other comorbidities or patient characteristics. Glycemic control should be of paramount importance prior to bariatric surgery to minimize the risk of complications.