Type 2 Diabetes Curable by Bariatric Surgery?

Bariatric procedures used for treating severe obesity has been studied as a cure for type 2 diabetes mellitus.
Studies have found that more than 75% of type 2 diabetes patients who undergo bariatric surgery no longer experience symptoms and no longer require insulin or other medications.
Obesity and type 2 diabetes are interrelated. Nearly 24 million Americans are affected by diabetes. About 50 percent of men and 70 percent of women who have the disease are obese; therefore bariatric surgery can have a sustained and meaningful effect on fighting both diseases.
In a study published by The American Journal of Medicine, 621 patients were studied from 1990 to April 2006. The results are as follows:
Study Results
Complete resolution of diabetes - 78.10%
Improved conditions - 8.50%
No changes - 13.40%

For years, researchers had assumed that weight loss alone was responsible for this benefit. However, new findings are demonstrating that hormonal and metabolic changes caused by the surgery, were responsible. The surgery helped patients lower fasting glucose, fasting insulin, and hemoglobin level.

According to the Wall Street Journal, diabetes can "quickly recede" when bariatric surgery "alters the intestinal tract and diverts food away from hormones in the small intestine that help regulate blood sugar levels".
Lowering hemoglobin (A1C) to below or around 7% has been shown to reduce microvascular and neuropathic complications of type 1 and type 2 diabetes. Therefore, for microvascular disease prevention, the A1C goal for nonpregnant adults in general is 7%.
On the other hand, researchers observed a progressive relationship between diabetes resolution and the weight loss operation performed:

Surgery Type
Laparoscopic adjustable gastric banding - 56.70% Resolution results - 46.20 Weight Loss
Gastroplasty - 79.90% Resolution results - 55.50% Weight Loss
Gastric bypass - 80.30% Resolution results - 59.70% Weight Loss
Biliopancreatic diversion/duodenal switch - 95.10% Resolution results - 63.60% Weight Loss

This study suggests that people with Type 2 diabetes and morbid obesity who get surgery before becoming insulin-dependent have the greatest chance for complete resolution and avoiding the progression of diabetes. However, physical activity and behavior modification are important for maintaining weight loss and for completely resolving diabetes.
On the other hand, the Agency for Healthcare Research and Quality (AHRQ) recently reported bariatric surgery is safer than ever. The risk of death from bariatric surgery has declined from 0.89 percent in 1998, to 0.19 percent in 2004.6.
"The severity of the diabetes at the time of surgery and the regain of excess weight loss long-term seem to be the primary determinants of long-term diabetes resolution after gastric bypass surgery," said James W. Maher, MD, professor of Surgery at Virginia Commonwealth University.

Although there are a number of effective, noninvasive treatments for diabetes, the American Society for Metabolic & Bariatric surgery (ASMBS) support the idea that Bariatric surgery should be considered for treating type 2 diabetes in morbidly obese adults, specially if the diabetes is difficult to control with lifestyle and pharmacologic therapy.
Finally, there is still insufficient evidence regarding the benefits of weight loss surgery in patients with BMI

For more information about Obesity and Diabetes or to get in touch with a Bariatric Surgeon Obesity and overweight issues affect over 100 million Americans.