Can A Gastric Bypass Procedure Have A Positive Impact On Diabetes?

By Chad Friedman, DPM, and Doug Pacaccio, DPM

   The complications stemming from obesity have been well documented. In recent years, the popularity of the gastric bypass procedure has increased as a method of combating obesity. As the literature shows, gastric bypass has a positive effect on diabetes itself as well as diabetic neuropathy. However, the surgery is not without its risks and the entire health care team must be aware of both the benefits and downsides.    According to data from the 1999-2000 National Health and Nutrition Examination Survey, two-thirds of the United States population is overweight and 30.5 percent of people are obese.1 This may lead to other commonly prevalent dilemmas including hypertension, heart disease and type 2 diabetes. This becomes a difficult task with the morbidly obese patients with diabetes who present with foot ulcers and have other foot deformities such as a Charcot foot.    When it comes to people who are overweight, the body mass index (BMI) may range between 25.0 to 29.9 kg/m2. For those who are obese, the BMI is greater than or equal to 30.0 kg/m2. These numbers are for adults who are age 20 and over. Among people diagnosed with type 2 diabetes, 67 percent have a BMI greater than 27 and 46 percent have a BMI greater than 30.2 An estimated 70 percent of diabetes risk in the U.S. can be attributed to excess weight.2

Should You Refer A Patient For Gastric Bypass?

   Given that podiatrists may treat lower extremity dilemmas in obese patients with diabetes, some patients may warrant an appropriate referral for a gastric bypass procedure.    In 1991, the National Institute of Health (NIH) consensus conference established guidelines and indications for surgical management of severe obesity.3,4 These include:    • a BMI equal to or greater than 40 kg/m2 or a BMI equal to or greater than 35 kg/m2 with significant comorbidities; and    • patients must have demonstrated previous dietary attempts at weight loss that have been ineffective.3    Also keep in mind that various multidisciplinary consults usually precede a patient undergoing a gastric bypass procedure. This multidisciplinary team may include a nutritionist, psychiatrist/psychologist, internist, cardiologist and various support groups.

How The Gastric Bypass Procedure Has Evolved Over The Years

   At the end of the 1800s and early 1900s, surgeons performed bypass on patients with peptic ulcers and also utilized the procedure as a treatment for stomach cancer. Obesity surgery began in 1954 at the University of Minnesota with the empiric use of intestinal bypass.3,5 Complications of intestinal bypass led to overgrowth of bacteria in the bypassed area of the bowel, kidney stone formation and cirrhosis. In 1966, researchers introduced gastric bypass at the University of Iowa with the belief that this surgery would restrict the intake of food without creating the complications of malabsorption that surgeons had observed with intestinal bypass.3    Today, the most frequent gastric bypass operation in the U.S. is the Roux en-Y gastric bypass, which Giffen introduced in 1977.3,5 Alkaline gastritis from early gastric bypass led to the Roux en-Y reconstruction. Other gastric bypass or bariatric bypass procedures are the vertical banded gastroplasty, the biliopancreatic diversion and the Lap-Band. Over the last decade, the popularity of gastric bypass has greatly increased since Wittgrove and Clark introduced laparoscopic techniques in 1994.3,7    The Roux en-Y procedure is a combination of a restrictive and a malabsorptive procedure. The malabsorptive aspect decreases the amount of calories absorbed and accordingly leads to weight loss while the restrictive aspect reduces the size of the stomach. Current restrictive procedures provide a very limited gastric reservoir that fills rapidly, leading to early satiety.3    The Roux en-Y procedure begins with creating a small pouch at the top of the stomach. The pouch is used to restrict the food intake. The surgeon would make the pouch by utilizing parallel surgical staples that divide the stomach into two parts. The smaller upper portion of the stomach will serve as the new stomach whereas the remaining portion of the stomach is intact so it can make its normal secretions into the duodenum.    The next step involves cutting a portion of the small intestine (bypassing the duodenum and the first portion of the jejunum) and connecting this to the small pouch of the stomach (the Roux Limb). This causes reduced calorie and nutrient absorption.8    The Roux limb allows food to pass directly from the small pouch of the stomach into the new connection, bypassing the remaining portion of the stomach, duodenum and the first part of the jejunum. The final step involves reconnecting the unused portion of the stomach and small intestine to the Roux limb with staples. This “y-connection” allows food to mix with pancreatic fluid and bile, aiding the absorption of important vitamins and minerals.9 The surgeon can alter the length of either segment of the intestine to produce lower or higher levels of malabsorption.10

Educating Patients On The Potential Pros And Cons

   When considering the possibility of referring a patient for this procedure, it is important that patients are aware of the possible risks.    Granted, with any surgery, there are always risks and possible side effects. However, bypassing of the duodenum interferes with iron and calcium absorption.3 This can lead to anemia as well as osteoporosis. Other risks include infection, gastritis, ulcers, vitamin B12 deficiency, loosening of the staples, hernia and dumping syndrome. Dumping syndrome occurs when there is a rapid emptying of the stomach contents into the small intestine.10 This happens when the patient has too much sugar or food. This can lead to nausea, vomiting, diarrhea, bloating, dizziness and sweating. Stomal stenosis may also occur. This involves a narrowing of the connection between the stomach and small intestine.    Yet studies have shown positive benefits of this procedure. A recent article from The American Journal of Surgery retrospectively looked at open Roux en-Y gastric bypass in 925 patients without mortality.11 The results from the study showed hypertension resolved in 70 percent of patients and diabetes mellitus resolved in 58 percent of patients. The series outperformed the national averages with excess weight losses of 40 percent at three months, 78 percent at 12 months and 84 percent at 18 months.11    Another study showed the effects of laparoscopic Roux-en-Y gastric bypass on patients with type 2 diabetes four years after the procedure. Fasting plasma glucose and glycosylated hemoglobin concentrations returned to normal levels (83 percent) or markedly improved (17 percent) in all patients.12 A significant reduction in the use of oral antidiabetic agents (80 percent) and insulin (79 percent) followed surgical treatment.12 Patients with the shortest duration (< five years), the mildest form of type 2 diabetes (diet controlled) and the greatest weight loss after surgery were most likely to achieve complete resolution of type 2 diabetes.12    Not only does gastric bypass help to resolve issues of type 2 diabetes but the procedure has also shown to improve diabetic neuropathy, hypertension, hypercholesterolemia and obstructive sleep apnea.

In Conclusion

   Given the promise of these studies and the potential benefit to patients who are obese and diabetic, podiatrists may want to consider referring patients for this procedure. As noted above, one should facilitate appropriate multidisciplinary consults and ensure that these patients have a strong understanding of the potential benefits and risks of the procedure. Dr. Friedman is a third-year resident at the Washington Hospital Center in Washington, D.C. Dr. Pacaccio is a third-year resident at Inova Health System in Fairfax, Va. Dr. Steinberg (pictured) is an Assistant Professor in the Department of Plastic Surgery at the Georgetown University School of Medicine in Washington, D.C. For related articles, please visit the archives at



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5. Kremen AJ, Linner LH, Nelson CH. An experimental evaluation of the nutritional importance of proximal and distal small intestine. Ann Surg 1954; 140:439-444.
6. Griffen WO, Young VL, Stevenson CC. A prospective comparison of gastric and jejunoileal bypass procedures for morbid obesity. Ann Surg 1977; 186:500-509.
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12. Schauer P, Ikramuddin S, et. al. Effect of Laparo scopic Roux-En-Y Gastric Bypass on Type 2 Diabetes Mellitus. Annals of Surgery. 2003;238:467-485.


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