Gastric Bypass More Effective Than Sleeves, But May Carry Hypoglycemia Risks: Study

More than a quarter of gastric bypass patients suffer from low blood sugar following the procedure, research shows.

A new study indicates roughly half of all patients who had gastric bypass weight loss surgery experienced remission of their type 2 diabetes, compared to just 20% of patients who had gastric sleeve surgery.

According to findings published in the May issue of the journal The Lancet Diabetes & Endocrinology, patients who had gastric bypass surgery not only went into remission for diabetes, but they also lost more weight and were less likely to suffer from acid reflux. However, gastric bypass patients were much more likely to experience dangerously low blood sugar levels, the data reveals.

Gastric bypass surgery and gastric sleeve procedures are both forms of bariatric weight loss surgeries. A gastric sleeve procedure, also known as a sleeve gastrectomy, permanently removes roughly 80% of the stomach. It reduces the size of the stomach and forces patients to eat much less in one sitting.

Roux-en-Y, or gastric bypass, involves dividing the stomach and rerouting it to the lower portion of the small intestine. It effectively closes off a part of the stomach so the body will not absorb all the calories from the food eaten.

In the new study, researchers from the Vestfold Hospital Trust in Tønsberg, Norway, compared gastric bypass and sleeve gastrectomy surgeries to determine if either had a better outcome on type 2 diabetes remission, weight loss and cardiovascular risk factors five years after surgery.

The team, led by Dr. Jostein Wågen Hauge, conducted a single center, triple-blind randomized controlled trial at a public obesity center in Norway from October 2012 to September 2017. The study included more than 100 obese adults over 18 years old with type 2 diabetes. They were randomly assigned to laparoscopic gastric bypass or sleeve gastrectomy surgery.

The findings indicate patients who had gastric bypass were more likely to experience type 2 diabetes remission, which occurred in more than 50% of gastric bypass patients, compared to only 20% of gastric sleeve patients.

Patients who had gastric bypass surgery lost roughly 22% of their weight, compared to 17% weight loss for gastric sleeve patients. The procedures had similar effects on cholesterol levels, with those undergoing gastric bypass having lower LDL cholesterol at follow-up than patients who had gastric sleeve surgery.

Researchers noted there was no difference between groups who experienced erosive esophagitis or Barrett’s esophagus. However, patients in the gastric sleeve group experienced pathological acid reflux more often.

Conversely, patients in the gastric bypass group experienced low blood sugar more frequently after eating than the gastric sleeve group. On average 28% of patients in the gastric bypass group experienced hypoglycemia after eating, versus just 2% of patients in the gastric sleeve group.

“Gastric bypass was superior to sleeve gastrectomy regarding long-term remission of type 2 diabetes, weight loss, and LDL cholesterol concentrations, at the expense of a higher frequency of symptomatic postprandial hypoglycaemia,” Hauge concluded. “These findings could inform clinical practice and future guidelines regarding the preferred surgical procedure in patients with type 2 diabetes.”

Weight Loss Surgery Concerns

The U.S. Food and Drug Administration (FDA) has approved nine weight loss surgeries since 1985, but only six are still available. Of those, gastric sleeve and gastric bypass are two of the most popular.

Recently the FDA called for public input to discuss the benefits and risks of weight loss surgical approaches since many studies have put forth conflicting conclusions about the effectiveness and safety of the procedures.

For example, two studies published in 2018 had competing outcomes. Data published by researchers from Finland concluded gastric bypass surgery is more effective than gastric sleeve to help reduce weight. However, another study published that same year which also indicated gastric bypass helped patients lose more weight, warned that gastric bypass patients often face a higher risk of adverse health complications as well.

A study published by French researchers indicated both gastric bypass and gastric sleeve surgeries are linked to an increased risk of complications, nutritional disorders and even alcohol dependence. Other studies have indicated bariatric surgeries make patients more likely to commit suicide or self-harm.