Data confirm long-term effects of bariatric surgery on type 2 diabetes

The 26th Annual Meeting of the American Society for Metabolic and Bariatric Surgery

The positive, long-term impact on the resolution of type 2 diabetes following bariatric surgery was confirmed in two studies presented at the 26th Annual Meeting of the American Society for Metabolic and Bariatric Surgery.

“This is a strong message to physicians and endocrinologists that gastric banding should be very seriously considered in the morbidly obese diabetic population because it offers the best chance to have better control or remission of their diabetes long-term,” Christine Ren, MD, associate professor of surgery at New York University School of Medicine, told Endocrine Today.

Ren and colleagues gathered preoperative data on 95 patients (mean age, 49.3) who underwent laparoscopic adjustable gastric banding between 2002 and 2004. Five-year follow-up data were collected beginning in 2008.

At the five-year follow-up, mean BMI decreased from 46.3 to 35.0 — a mean value of 48.3% excess weight-loss.

“There was a sustained benefit — about 40% of patients had complete remission in their diabetes. This was confirmed with normal fasting blood sugar, normal HbA1c and they were completely off all medications including insulin,” Ren said. “In addition, there were another 40% of patients who had improvements in diabetes as shown by a decrease in their medication, improvements in fasting blood glucose control and improveents in HbA1c.” Diabetes was resolved in 43% of patients, for a total improvement/resolution rate of 83%.

About 88% of patients were taking antidiabetes therapies before the procedure, which decreased to about 47% at the five-year follow-up. In addition, about 15% of patients were using insulin preoperatively, and use decreased to about 9% at follow-up.

Mean fasting glucose decreased from 146 mg/dL preoperatively to 118.5 mg/dL at five years; mean HbA1c decreased from 7.53% to 6.58% (P<.001).

Diabetes-free five to 16 years following surgery

In another study, researchers from Virginia Commonwealth University examined 177 patients (147 females) with diabetes who underwent Roux-en-Y gastric bypass surgery between 1993 and 2003. Follow-up was between five and 16 years.

Patients were divided into three groups based upon treatment prior to surgery: insulin dependent (n=59), oral medication (n=83) and diet and lifestyle intervention only (n=35).

Complete resolution was achieved in 157 patients who also had a decrease in mean BMI from 50.2 before surgery to 31.3 after surgery. Forty-three percent of these patients subsequently had type 2 diabetes recurrence and associated weight gain. Twenty patients did not achieve complete resolution of type 2 diabetes despite mean excess weight of 58.2% (P<.0009).

Patients controlled on diet or oral medication before surgery were 10 times as likely as insulin-controlled patients with diabetes to have a durable remission (.5 years).

“When looking at the insulin-controlled diabetic patients, 80% had resolution at some point, but recurred in 72%,” James W. Maher, MD, professor of surgery at the University, said during an interview. “The durability of resolution seems to correlate inversely with the severity of the disease — insulin-dependent diabetics were most likely to have recurrence and patients who initially underwent dietary control were very likely to have a long-term positive result.”

“There are a lot of data out there that gastric bypass improves type 2 diabetes and we certainly noticed that in our own patients, but we also noticed that over time it seemed to come back in at least some of them,” he said. “So, if the physician has a candidate for weight-loss surgery to treat diabetes, it should come early in the course of their disease. If they get to the point of insulin dependence they may have a pancreas that does not have very much reserve in the insulin producing cells and therefore a long-term remission may not be achieved.” – by Jennifer Southall

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