Bariatric surgery may cure diabetes in some patients

Study being conducted by : Thomas Rogula MD, Stacy Brethauer MD, Bipand Chand MD, and Philip Schauer, MD

“Gastric bypass surgery has become a popular option for obese people who want to shed pounds quickly, but diabetics also have something to gain from the procedure: the surgery can resolve type 2 diabetes”.

WHAT IS DIABETES?

Diabetes currently affects more than 150 million people worldwide and that number is expected to quickly increase. Over 90% of people with the disease have the Type 2 form, which is associated with obesity and overweight, lack of physical activity, family history and older age. Unlike Type 1 diabetes in which the pancreas fails to produce sufficient insulin, the pancreas in patients with Type 2 diabetes produces enough insulin, but for unknown reasons, the body is unable to use the insulin. Diabetes can lead to blindness, heart and blood vessel disease, strokes, kidney failure, amputations, and nerve damage. Current therapies, which include diet, exercise, oral antidiabetic drugs and insulin, do not always cure the disease.

TRADITIONAL THERAPY FOR DIABETES

The goal of treatment is to improve the symptoms of diabetes through normalizing blood glucose levels. The ongoing goals are to prevent long-term complications like eye and kidney disease, damage of nerves and blood vessels. Strict control of blood glucose reduces risk of death, stroke, heart failure, and other complications. Glycosylated hemoglobin (HbA1C) is a test that determines risk for long-term complications. It measures how much glucose has been sticking to red blood cells and other cells.

The first-line treatment for type 2 diabetes is weight loss, diet and exercise. Appropriate meal planning includes choosing healthy foods and eating the right amount of food. Exercise is important for effective treatment of diabetes. Regular exercising helps burn excess calories, managing weight thus improves control of the glucose amount in the blood.

When diet and exercise are not sufficient to maintain normal blood glucose levels, medications may be needed. They work through triggering the pancreas to make more insulin, helping insulin work better, decreasing the absorption of carbohydrates from the gut or decreasing glucose production in the liver. Poor blood glucose control despite lifestyle changes and taking medications means insulin should be injected.

SURGERY IS THE BEST THERAPY FOR SEVERE OBESITY

Dietary and medical therapy for severe obesity has limited short-term success and almost nonexistent long-term success. Therefore, obesity surgery (also called bariatric surgery) has been a popular treatment in the war against obesity. Bariatric surgery generally results in greater and sustained weight loss than conventional treatment, and leads to improvements in quality of life and obesity related diseases such as diabetes, hypertension, sleep apnoea (when breathing stops for short periods during sleep) and many others.

Bariatric operations currently performed include stomach restriction sleeve gastrectomy and combined restrictive and malabsorptive procedures (Roux-en-Y gastric bypass or the mini gastric bypass).

Bariatric surgery, formerly used only for treating obesity, is now being explored as a cure for type 2 diabetes not only in obese patients but also in normal weight or moderately overweight people. The Cleveland Clinic Bariatric and Metabolic Institute is currently conducting pioneering studies in this matter.

A recent study on over 20,000 patients showed that 84 percent who underwent Roux-en- Y gastric bypass (RYGB) experienced complete reversal of their type 2 diabetes. Rapid improvement in blood sugars and reduction or elimination of diabetic medications is often seen within the immediate period following bariatric surgery, even before significant weight loss. While the number of diabetic patients needing medical therapy with oral hypoglycemics or insulin reaches almost 90 percent over time, the need for medical management falls to less than 8 percent among those who have gastric bypass. These results are typically persistent for rest of the life, as long as normal body weight is sustained. Resolution of diabetes is measured by normalized fasting blood sugar and glycosylated hemoglobin (HgA1C) concentrations. Some studies show that every 1 percent drop in HbA1C causes a relative reduction of long-term complications of diabetes by 25 to 45 percent.

Patients having a milder form of diabetes (controlled with diet) for less than five years, and who achieve greater weight loss after surgery, are more likely to achieve complete resolution of diabetes mellitus. Bariatric surgery plays important role in prevention of diabetes: weight loss following gastric bypass in obese non-diabetic patients decreases their likelihood of developing diabetes by 60 percent.

Bariatric surgery ameliorates diabetes independently of weight loss, through mechanisms that remain unclear. Bariatric gastric bypass surgery, improves diabetes through weight loss, by exclusion (bypassing) of the initial portion of the jejunum from the flow of nutrients and by altering production of various gut hormones leading to improvement of insulin secretion and resistance. Despite of the hypothetical mechanism, Roux-en-Y gastric bypass and now the Mini Gastric Bypass based on data are proving the most powerful operation to control diabetes.

THE EARLIER THE SURGERY, THE BETTER THE OUTCOME

A key finding of many studies is that the shorter the history of diabetes, the greater the likelihood of complete remission. Glucose toxicity, particularly in poorly controlled diabetes, accelerates B-cell failure. B-cells are located in the pancreas and produce and secrete insulin. Weight loss can improve B-cell responsiveness to glucose. If the bariatric surgical procedure is performed before irreversible B-cell failure has occurred, durable weight loss will be accompanied by a high likelihood of long-term remission.