Gastric Bypass Surgery Less Helpful for Diabetics

But despite the fact that diabetes patients lost less weight after surgery than patients without the disease, 90% of the former group still saw their blood-sugar levels fall after the procedure. That meant they could also cut back significantly on the amount of medication they needed. According to Dr. Osama Hamdy, director of the Obesity Clinical Program at Joslin Diabetes Center, the chances may be even better for those patients who address their diabetes early on. "If you have had diabetes for a long time, your response to surgery may not be as good as that of people who have had diabetes for a short period of time," he says. "People who have had a longer duration of diabetes may reduce their medication, but they may never be able to stop them completely."

Campos' study did not stratify the diabetes patients in his study by how long they had been living with their disease. But researchers think the benefits of gastric bypass may indeed be greatest in those obese patients who are recently diagnosed with diabetes, since their bodies are more likely to revert back to normal sugar metabolism after surgery. That's because much of the post-bypass weight loss is spurred by a shift in the hormonal feedback loop that controls hunger and satiety. Production of certain weight-related hormones, such as ghrelin, or the hunger hormone, are directly reduced by the patient's physically smaller stomach (ghrelin is produced by glands in the stomach), leading to a reduction in food intake. Meanwhile, the smaller stomach more readily triggers hormones that signal satiety to the brain, sending the message that the body has taken in its fill of calories. But the longer this system has been overwhelmed with too much sugar and too many calories as occurs in diabetes, experts suspect, the more difficult it is to normalize the body's metabolic thresholds and molecular messages.

"I believe that the benefits of gastric bypass surgery outweigh any risk that a patient will have," says Hamdy. "If you look at the mortality in relation to obesity itself, especially if it occurs with diabetics, that is much, much higher than the risk of mortality from the surgery."

What Campos' study shows, however, is that patients should have realistic expectations of what the surgery can do for them: People without diabetes have the best chance of losing weight and reaping the heart and metabolic benefits of being slimmer; among diabetes patients, those undergoing surgery early on in their disease might fare better than those who wait longer. Both Campos and Hamdy remind patients that surgery is never the final answer — weight-loss maintenance continues long after you're discharged from the hospital, and can only be done the old-fashioned way, with a healthy diet and exercise plan. Surgery, after all, can only get you so far.