About 20 million Americans currently have type 2 diabetes, three times more than in 1980. Diabetes is a major risk factor for stroke and heart attack, is the leading cause of new cases of blindness, and is the largest cause of the need for dialysis. Diabetes is also usually progressive, meaning that on the same medications and on the same diet and exercise regimen, the blood sugar of a patient with diabetes will slowly increase, necessitating constantly increasing amounts of medications.

So despite new families of medications for diabetes, and despite the fact that most patients require more than one medication, many patients never achieve good control of their blood sugar.

Two studies published this week in the New England Journal of Medicine offer tantalizing hope for overweight patients with diabetes. Both studies attempted to discover whether overweight patients with diabetes would achieve better control of their diabetes through weight loss surgery or through standard medical care.

One study, conducted in Italy, randomized 60 patients to three groups. One group was treated with medication. Another underwent gastric bypass surgery. The third group underwent biliopancreatic diversion surgery. (See the helpful graphic in the NY Times article for an explanation of the different surgeries. I thought biliopancreatic diversion was the name of a gastroenterology theme park.) The endpoint of this study was very ambitious – remission of diabetes, defined as normal sugars without medication for over a year.

None of the patients receiving medical therapy achieved remission, compared with 75% of the patients who underwent gastric bypass, and 95% of the patients undergoing biliopancreatic diversion.

The second study, from the Cleveland Clinic, randomized 150 overweight diabetic patients to gastric bypass, sleeve gastrectomy, or medical therapy. The patients in the surgical groups had much better control of their diabetes than the medical therapy group, and many in the surgical group were able to stop their diabetes medications.

Those are very impressive results, but some questions remain unanswered. Does the remission of diabetes mean that the patient is cured? We don’t know. Since the studies followed patients for at most two years, it is entirely possible that years from now their diabetes will recur. Will the excellent control of diabetes translate to fewer diabetic complications, like strokes, heart attacks, and kidney disease? Do diabetics who are less overweight than those in these studies still benefit from surgery? Larger long-term studies will be needed to find out.

But for now it is clear that for overweight patients with diabetes, surgery should no longer be thought of as a last resort. Surgery is increasingly a proven therapy with much greater effectiveness than other alternatives.

Learn more:

Weight-loss surgery effective against diabetes, studies show (LA Times article)
Surgery for Diabetes May Be Better Than Standard Treatment (NY Times article)
Bariatric Surgery (NY Times, instructional diagrams explaining the anatomy of various weight loss surgeries)
Bariatric Surgery versus Conventional Medical Therapy for Type 2 Diabetes (New England Journal of Medicine article)
Bariatric Surgery versus Intensive Medical Therapy in Obese Patients with Diabetes (New England Journal of Medicine article)
Surgery or Medical Therapy for Obese Patients with Type 2 Diabetes? (New England Journal of Medicine editorial)
Evidence Mounts in favor of Weight Loss Surgery (My last post about weight loss surgery in 2011, with links to my previous posts about this topic)