The effects of optimal perioperative glucose control on morbidly obese patients undergoing bariatric surgery

Background: Bariatric surgery is the most effective treatment for morbidly obese type II diabetics. However, guidelines for perioperative glucose control are not well established. We examined management of perioperative glucose levels in diabetic patients undergoing bariatric surgery and determined the impact of optimal glucose control as defined by the American Society for Metabolic and Bariatric Surgery (ASMBS) on patient outcomes, including long-term diabetes resolution. Methods: A single-institution, retrospective analysis of 155 morbidly obese diabetic patients who underwent laparoscopic gastric bypass (RYGB) or sleeve gastrectomy (LSG) from 2010 to 2014 was performed. Inpatient finger-stick glucose levels were extracted from the electronic health record and defined as optimal if all values were <180 mg/dl. Ninety-day and one-year outcomes, including diabetes resolution, medication management, mortality and total costs were compared for patients with and without optimal control. Results: 80 % (n = 124) of patients with type II diabetes underwent RYGB, while the remaining patients underwent LSG. Diabetes resolution at 1 year was 70.1 % (73.4 % for RYGB and 53.9 % for LSG, p = 0.191). Preoperatively, 72 % (n = 112) of patients were taking one or more oral antihyperglycemic agents, while only 50.3 % (n = 78) took an oral medication on discharge. 93 % of RYGB and 82 % of LSG patients, respectively, reduced their long-acting insulin dosage by greater than 50 % upon discharge (p = 0.251). Ninety-day and one-year outcomes including total costs were not improved by optimal perioperative glucose control. In total, 96.7 % of optimally controlled patients experienced diabetes resolution at 1 year compared to 53.2 % in the non-optimally controlled group (p < 0.001). Conclusion: Bariatric surgery leads to significant resolution of type II diabetes and a prompt improvement in glucose tolerance in the perioperative period. Optimal glucose control as defined by the ASMBS was not associated with improved postoperative outcomes in our patient population but was highly predictive of long-term diabetes resolution.