Bariatric Surgery Cuts Insulin Needs in T1D With Obesity

Mitchel L. Zoler, PhD

June 17, 2021

While bariatric surgery does nothing to directly improve the disease of patients with type 1 diabetes, it can work indirectly by moderating severe obesity and improving insulin sensitivity to cut the total insulin needs of patients with type 1 diabetes and obesity, based on a single-center, retrospective chart review of 38 U.S. patients.

Two years following their bariatric surgery, these 38 patients with confirmed type 1 diabetes and an average body mass index of 43 kg/m2 before surgery saw their average daily insulin requirement nearly halved, dropping from 118 units/day to 60 units/day, a significant decrease, Brian J. Dessify, DO, said in a presentation at the annual meeting of the American Society for Metabolic and Bariatric Surgery.

Another measure of this effect showed that the percentage of patients who required more than one drug for treating their hyperglycemia fell from 66% before surgery to 52% 2 years after surgery, a change that was not statistically significant, said Dessify, a bariatric surgeon at Geisinger Medical Center in Danville, Pa.

Appropriate for Patients With 'Double Diabetes '

These results "provide good evidence for [using] bariatric surgery" in people with both obesity and type 1 diabetes," he concluded. This includes people with what Dessify called "double diabetes," meaning that they do not make endogenous insulin, and are also resistant to the effects of exogenous insulin and hence have features of both type 2 and type 1 diabetes.

"This is a really important study," commented Ali Aminian, MD, director of the Bariatric and Metabolic Institute of the Cleveland Clinic. "For patients with type 1 diabetes, the primary goal of bariatric surgery is weight loss and improvement of obesity-related comorbidities. Patients with type 2 diabetes can be a candidate for bariatric surgery regardless of their weight," Aminian said as designated discussant for the report.

"The goal of bariatric surgery in patients with type 1 diabetes is to promote sensitivity to the exogenous insulin they receive," agreed Julie Kim, MD, a bariatric surgeon at Mount Auburn Hospital in Waltham, Mass., and a second discussant for the report. Patients with double diabetes "are probably a subclass of patients [with type 1 diabetes] who might benefit even more from bariatric surgery."

Using Gastric Sleeves to Avoid Diabetic Ketoacidosis

Aminian also noted that "at the Cleveland Clinic we consider a sleeve gastrectomy the procedure of choice" for patients with type 1 diabetes or type 2 diabetes with insulin insufficiency "unless the patient has an absolute contraindication" because of the increased risk for diabetic ketoacidosis in these patients "undergoing any surgery, including bariatric surgery." Patients with insulin insufficiency "require intensive diabetes and insulin management preoperatively to reduce their risk for developing diabetic ketoacidosis," and using a sleeve rather than bypass generally results in "more reliable absorption of carbohydrates and nutrients" while also reducing the risk for hypoglycemia, Aminian said.

In the series reported by Dessify, 33 patients underwent gastric bypass and 5 had sleeve gastrectomy. The decision to use bypass usually stemmed from its "marginal" improvement in weight loss, compared with a sleeve procedure, and an overall preference at Geisinger for bypass procedures. Dessify added that he had not yet run a comprehensive assessment of diabetic ketoacidosis complications among patients in his reported series.

Those 38 patients underwent their bariatric procedure during 2002-2019, constituting fewer than 1% of the 4,549 total bariatric surgeries done at Geisinger during that period. The 38 patients with type 1 diabetes averaged 41 years of age, 33 (87%) were women, and 37 (97%) were White. Dessify and associates undertook this review "to help provide supporting evidence for using bariatric surgery in people with obesity and type 1 diabetes," he noted.

Dessify, Aminian, and Kim had no disclosures.

This article originally appeared on, part of the Medscape Professional Network.


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.