In Type 2 diabetes, weight management and blood sugar control are closely intertwined. Patients find that eating healthier food, exercising and losing weight are directly related to achieving lower, stable blood sugar levels — which is critical to avoiding the disease’s insidious complications. For some people, however, losing significant weight and keeping it off is difficult or impossible, despite their best efforts.
As weight-loss surgery has evolved and become more common, researchers wondered if these procedures could help people with tough-to-control diabetes get a better handle on their blood sugar (or glucose) and improve their quality of life. Now, a newly released, five-year study suggests the answer is yes.
The research, published Wednesday in the New England Journal of Medicine, pitted two kinds of weight-loss surgery against intensive medical treatment alone in obese patients with hard-to-control Type 2 diabetes. Those who had either procedure experienced better blood sugar control, showed more improvement in cholesterol levels and maintained a higher percentage of weight loss at the five-year milestone.
Of the 150 original participants, one nonsurgical patient died. In all, 134 were available for the final evaluation. The average age of participants was 49 and two-thirds were women.
[See: 10 Ways to Prepare for Surgery.]
Participants were randomly assigned to three groups: one to undergo gastric bypass surgery, another, sleeve gastrectomy and a third to have no surgery. Both surgical groups got regular evaluations by an endocrinologist, took medications like metformin to control blood sugar as needed and received dietary counseling and lifestyle advice.
The nonsurgical group was assigned to the same intensive medical regimen of tight blood glucose monitoring and medication, close follow-up by doctors and lifestyle counseling alone.
On average, gastric bypass patients lost 23 percent of their body weight; sleeve gastrectomy patients lost 19 percent and medical-therapy-only patients lost 5 percent from their baseline.
Both surgical methods are designed to yield weight loss via different mechanisms. Gastric bypass surgery is the more invasive option, involving cutting and stapling of the stomach and rearranging or rerouting the small bowel. By changing how the digestive system handles food, gastric bypass surgery helps patients lose weight. Because the stomach is made smaller, patients feel satisfied with less food.
Sleeve gastrectomy is performed through small incisions in the abdomen. Surgeons remove most of the stomach, leaving a narrow gastric tube or “sleeve.”
In the past, only severely obese patients were considered for weight-loss surgery. But as the benefits of bariatric surgery have become clearer, it is now being recommended for people with more moderate obesity according to their body mass index. BMI is a ratio of weight to height. A BMI between 25 and 30 is classified as overweight, while a BMI of 30 or more is classified as obese. The BMI range for study participants was 27 to 43 at the study’s start, with an average BMI of 37.
The surgery groups also benefited in another important way: They got their blood sugar levels under much tighter control compared to their medication-only peers. Tight blood sugar control is important for staving off diabetes side effects including high blood pressure, increased stroke risk, poor wound healing, vision loss, kidney disease and circulation problems that sometimes lead to amputation.
Better control was evidenced by participants’ A1C levels, a measurement of average blood sugar over several months. Specifically, 29 percent of gastric bypass patients met the primary study goal of maintaining an A1C level of 6 percent or less, with or without diabetes medication, as did 23 percent of the sleeve gastrectomy patients. But just 5 percent of the medication-only group hit that goal.
What’s more, a majority of the surgical patients no longer required insulin at the five-year study end point.
“That’s a major finding because taking multiple shots of insulin is extremely burdensome for people with diabetes,” says study co-investigator Dr. Sangeeta Kashyap, an endocrinologist at Cleveland Clinic’s Endocrinology and Metabolism Institute. The finding, she says, is a sign that surgery helps.
In diabetes, insulin — a naturally occurring hormone that helps the body break down sugar — is either lacking entirely or cannot be properly used by the body as cells become resistant. While all people with Type 1 diabetes require insulin therapy to survive, oral medications like metformin are enough for many Type 2 patients. However, as blood-sugar control worsens, Type 2 patients may also need insulin injections.
[See: The 12 Best Diets to Prevent and Manage Diabetes.]
Cholesterol levels — which can also remain stubbornly high among some Type 2 diabetes patients and increase heart-disease risk — improved the most for gastric bypass patients, followed by the sleeve gastrectomy group; the same pattern held for various quality-of-life measures, such as physical functioning, general health and energy levels, which were significantly higher by study’s end for both surgical groups.
By contrast, quality of life did not significantly improve for the medication-only group. Instead, bodily pain and emotional well-being significantly worsened, the researchers wrote.
The results, Kashyap says, are clinically relevant for people with difficult-to-control diabetes, even those who aren’t necessarily severely obese.
The study was funded by the Cleveland Clinic and a National Institutes of Health grant. It received industry support from Ethicon, which makes surgical equipment used in bariatric procedures, and LifeScan, which produces blood glucose-monitoring supplies.
The Downsides of Weight-Loss Surgery
The new research findings came as little surprise to Dr. Pauline Camacho, president of the American Association of Clinical Endocrinologists, who was not involved with the study.
“For clinicians like me who have seen patients undergo bariatric surgery, it’s kind of intuitive,” that the attendant weight loss would lead to better diabetes control, says Camacho, who is a professor of medicine at Loyola University Medical Center and director of the Loyola University Osteoporosis and Metabolic Bone Disease Center, near Chicago. “We see it; we expect it. It’s nice to see it in a large-scale controlled trial.”
However, Camacho adds, the long-term, adverse effects of bariatric surgery, particularly gastric bypass, could have been more thoroughly addressed in the study. And it’s definitely something patients should consider before undergoing life-changing surgery.
“We also, as endocrinologists, are recipients of a lot of patients who undergo this kind of surgery,” Camacho says. “And they suffer from vitamin B deficiency; they suffer from bone loss; malabsorption — and that’s not necessarily highlighted in the study. Just like there is an upside, there’s also a downside.”
Because gastric bypass surgery shrinks people’s stomach size and essentially reroutes their digestive system, smaller meals are necessary, lest there be unpleasant consequences. Vitamin D deficiency is a top nutritional issue after gastric bypass surgery, Camacho says. Vitamin B-12 and iron deficiency are also surgical side effects, along with anemia. Episodes of too-low blood sugar, or hypoglycemia, are another after-effect of bariatric procedures, she notes, especially in patients who’ve had gastric bypass. Bowel habits can be disrupted.
With surgery, Camacho says, “The upside, of course, is weight loss, quality of life increase and diabetes control, as well as improvement in lipids,” like cholesterol levels. Among people who might benefit from a referral for possible weight-loss surgery, she says, “It would really be that population of patients who are morbidly obese and have very poor diabetes control … and the other [symptoms], too, like hypertension and high cholesterol. And you’ve nearly maxed out their medical therapy.”
The data are clear that gastric surgery will improve diabetes control and lead to weight loss, Camacho says: “But there should be a careful discussion with the treating physician about these adverse events.”
When Other Options Are Exhausted
By the time people with diabetes enter a clinical trial in which they’ll be assigned to surgery or intensive medical therapy (as they were for the new study), other options have failed, Kashyap says. “Patients who are well-controlled, who benefited from lifestyle and medication, probably would not be all that eager to sign up for a study like this,” she says.
For her patients with stubborn diabetes and weight issues, Kashyap says, the first step is using counseling, diet, exercise and medication to try and get their weight in check. After six months to a year, she says, “If they’re not making much progress and I notice their body mass is 35 or greater, they get a referral to bariatric surgery.”
Whether the new study results apply to others with diabetes depends on the individual. “If somebody’s out there [with] Type 2 diabetes [that’s] controlled well on metformin, I don’t think they’d be the best person to take this information to heart,” Kashyap says. On the other hand, she adds: “If they’re on metformin and another drug and they’re on 100 units of insulin and their body mass index is 36, they may be just perfect for something like this.”
When someone is interested in considering weight-loss surgery for diabetes, an endocrinologist can assess whether they’re a good candidate, and if so, refer them to a bariatric surgery center for evaluation.
[See: What Not to Say When Someone Loses Major Weight.]
Getting approved for weight-loss surgery is not a simple process, Kashyap notes. Patients must undergo physical exams and psychological evaluations, including screening for substance abuse. They also receive education about what to expect. “There are a lot of changes that are going to happen to these folks,” she says. “Their diet is going to change radically. Also their mindset.” The point is for people to do well in the long term after surgery, she adds. “That’s an important part of any bariatric program.”
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Weight-Loss Surgery May Top Medication Alone for Hard-to-Control Diabetes originally appeared on usnews.com
