Bariatric (Weight-Loss) Surgery for Treating Diabetes


Does bariatric surgery treat type 2 diabetes?

Doctors have found that weight-loss surgery can treat type 2 diabetes by managing the level of sugar in the blood. Diabetes is a disease that happens when blood sugar (blood glucose) levels are too high. Blood sugar is the primary source of energy for your cells. Glucose is able to get into cells because of a hormone called insulin. Insulin is made by the pancreas.

If your body does not make insulin or make enough insulin, the glucose cannot get to your cells and so stays in the blood. This situation, if it lasts a long time, can cause certain health problems. Complications of diabetes can be very serious. They can affect the eyes, kidneys and nerves.

Obesity is an important factor in developing diabetes. People who have obesity have 10 times the risk of developing the disease. Foods that are high in fats and carbohydrates increases fatty acids in the blood and lipid (fat) build-up in the liver and muscles. This increases insulin resistance and inflammation. Over time, the pancreas stops making enough insulin.

Weight-loss surgery is also called bariatric surgery. There are several types. Most of the procedures can be done in a minimally invasive way, via laparoscopy. Laparoscopic surgeries involve only small incisions and very tiny instruments.

Who is eligible for weight-loss surgery?

  • You’re more than 100 lbs. over your ideal body weight.
  • You have a Body Mass Index (BMI) of over 40.
  • You have a BMI of over 35 and are experiencing severe negative health effects, such as high blood pressure or diabetes, related to obesity.
  • You can’t achieve a weight that’s healthy for you for a sustained period of time, even through medically-supervised dieting.

For bariatric surgery to treat diabetes:

  • If you have a BMI of 35 or more with type 2 diabetes and/or other illnesses related to excess weight, and have not been able to achieve normal fasting blood sugar (less than 125 mg/dl or HbA1c less than 7 percent), you probably are a candidate for diabetes surgery.
  • In some cases when diabetes is hard to manage, people may be eligible for bariatric surgery even if they have a BMI of less than 35.

Procedure Details

What are the types of weight-loss surgery?

Laparoscopic Roux-en-Y Gastric Bypass

Roux-en-y, stomach, stomach pouch, pancreas, food, digestive juice, duodenum, jenunum

How it works: This procedure involves creating a small stomach pouch. This reduces the amount of food you can eat. The intestine is connected to the new pouch and rerouted. The pouch is connected directly to the lower part of the small intestine. Food bypasses the lower stomach, the first part of the small intestine (duodenum) and some of the second part (jejunum). The changes created during gastric bypass cause changes in the way the gut and the pancreas interact. This affects diabetes management even before weight is lost. Patients generally can return to work within three to four weeks. Gastric bypass is a good surgical option in many patients.

Laparoscopic Sleeve Gastrectomy (LSG)

Sleeve gastrectomy with disected fundus placement, normal stomach, smaller stomach, food, pancreas

How it works: LSG reduces the size of the stomach and limits food intake. LSG is technically easier to perform than gastric bypass and is a good surgical option in many patients. Patients who are at risk for undergoing anesthesia, or who have a heart or lung problem and should not undergo a long surgery, may also benefit from this surgery. Patients generally stay in hospital for one night and can return to work within three to four weeks.

Duodenal Switch (DS)

duodenal switch, duodenum, jejunum, smaller stomach, pancreas, food, ileum

How it works: DS is another procedure that results in calories not being absorbed well. DS is a combination of LSG and a large bypass procedure. The procedure creates a smaller stomach that is connected to the farthest part of the small intestine. The duodenum, jejunum and part of the proximal ileum are bypassed and then connected to a point near the ileocecal valve. The surgery is effective, but also riskier than other procedures. It is generally only for people who have BMI higher than 50.

Risks / Benefits

What are the benefits of weight-loss surgery?

A majority of patients lose 50 to 80% of the excess weight during the 18 to 24 months after surgery. However, the effects on blood sugar are immediate (within days) after surgery. People who have this surgery can reduce or eliminate diabetes medications.

In particular, Roux-en-Y surgery is effective at diabetes management. About 33% of these patients do not need diabetes drugs after surgery. Within 2 years of surgery, a total of 85% of patients do not require medication. Their diabetes is in remission.

Complete resolution of diabetes is more common among people who have a form of diabetes that does not require medication and who have had diabetes less than five years. Resolution is also more common among people who have more weight loss after surgery. The benefits extend to high blood pressure and high cholesterol. These factors, which increase the risk of strokes and heart attacks, are also improved and/or resolved after surgery.

What are the risks of weight-loss surgery?

Risks associated with these surgeries may include:

  • Poor response to anesthesia.
  • Damage to nearby organs during surgery.
  • Bleeding.
  • Blood clot formation.
  • Infection.
  • Peritonitis, or inflammation in the peritoneum, the tissue that covers and supports the organs in the abdomen.

Other risks may include:

  • Blockages in the intestine.
  • Development of gallstones and kidney stones.
  • Narrowing of the connection between the stomach and the intestine, also called anastomotic stenosis.
  • Dumping syndrome (early and late): nausea, stomach pain and vomiting after eating.
  • Malnutrition.

Recovery and Outlook

What is the outlook for people who have bariatric surgery to treat diabetes?

The improvements to blood glucose may start right after the surgery. You will probably be able to reduce the dosage of the diabetes medications. You might even be able to stop taking medications entirely. You will reduce your chances of heart attacks, strokes, and heart and kidney failures. You might be able to stop taking medications for those conditions as well. Sleep apnea and fatty liver should improve.

You will lose weight in the short term and over the long term if you follow the instructions on when to eat, what to eat, and how much to eat. At first, you will have a liquid diet. Over the first month, the diet will transition to solid food with the help of your dietitian.

Depending on the type of surgery and how you heal, you can probably return to work in 3-4 weeks.

You will be asked to keep the scheduled appointments after the surgery for

  • Follow-up after surgery (generally 1 week, 1 month, and then once a year)
  • Lab work (at 6 months, one year, and then once a year)
  • Dietary counseling (at one month, 3 months and then as needed)
  • Psychological counseling (at one month and then as needed) and exercise counseling (at one month and then as needed).
  • Routine healthcare with your primary healthcare provider (as needed)
  • Monthly support group attendance

When to Call the Doctor

When should you contact your healthcare provider if you have had weight-loss surgery?

In the short term, your healthcare team will provide a list of when you should contact the doctor, such as if you:

  • Develop a fever.
  • Have increasing pain or new pain.
  • Have any issues with your incision that point to infection.
  • Are constantly vomiting or unable to eat.
  • Are extremely constipated.

In the long term, while surgery is helpful in treating diabetes and sleep apnea, it will work best over time if you follow directions about eating, taking vitamins, and exercising. If you develop grazing habits (eating a little bit throughout the day), you may gain weight (without experiencing dumping syndrome).

It is also important to pay attention to other habits that could be problems, like drinking too much, smoking, or using opioids. You should make sure to talk to your healthcare provider if you have thoughts of suicide.

Additional Details

Will insurance cover the surgery?

Most insurance policies do cover the surgery. You should contact your insurance provider to find out if your policy does provide coverage.

Last reviewed by a Cleveland Clinic medical professional on 10/17/2019.


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