Gastric Bypass More Effective Than Sleeves, Bands for Weight Loss, But Carry More Risks: Study

Individuals who undergo gastric bypass surgery tend to lose more weight, but face higher rates of complications and side effects than other types of weight loss surgeries. 

According to findings published in the Annals of Internal Medicine last month, researchers indicate that Roux-en-y surgery, more commonly referred to as gastric bypass, is more effective than sleeve gastrectomy and gastric banding procedures, but carries more long-term risks.

Researchers analyzed data from 41 health systems in the National Patient-Centered Clinical Research Network, from January 2005 to September 2015. More than 65,000 patients ages 20 to 79 years old were included in the study, each of which had a body mass index of 35 kg/m² or greater and underwent a bariatric procedure.

The study group included a total of 32,000 patients who underwent gastric bypass, nearly 30,000 patients who underwent sleeve gastrectomy, or gastric sleeve surgery, and 3,200 patients who underwent adjustable gastric banding, or lap band surgery.

Researchers measured the estimated percent total weight loss at one, three and five years after surgery. They also compared 30-day rates of major adverse events and complications.

Patients who underwent gastric bypass surgery lost the greatest amount of weight overall. Despite the increased weight loss, which can reduce incidence of other health conditions, those patients experienced higher rates of adverse events within 30 days after the surgery.

By one year after the surgery, patients who had gastric bypass lost 31% of their total body weight. Patients who had the gastric sleeve lost 25% and those who had lap band lost nearly 14%.

At the five year mark after surgery, patients who underwent gastric bypass lost a total of 25% of their body weight. Comparatively, those who underwent gastric sleeve lost nearly 19% of body weight and those who had the lap band procedure lost nearly 12%.

However, patients who had gastric bypass experienced higher rates of death and venous thrombosis. The 30 day rate of major adverse events was 5% among gastric bypass patients, 2.6% for gastric sleeve patients, and 2.9% for lap band patients.

The death rate within 30 days of the surgery was 0.2% of for gastric bypass patients and 0.1% for gastric sleeve patients.

Venous thrombosis occurred in 0.7% of gastric bypass patients and 0.6% of gastric sleeve patients.

Researchers note the difference in complication rates was mostly attributed to the need for re-intervention after surgery. Patients who had gastric bypass had a 4% re-intervention rate and those who had gastric sleeve had a much lower re-intervention rate at 1.9%.

Study authors also noted patients with diabetes, a body mass index of less than 50, those over 65 years old, African American patients, and Hispanic patients lost the least amount of  weight overall.

A similar study published earlier this year indicated gastric sleeve surgery was not as effective as gastric bypass surgery. Patients undergoing gastric bypass lost more weight overall and were able to reduce the number of medications needed for other health problems. Gastric bypass surgery seems to outperform other surgeries in terms of total weight loss.

“Bariatric surgical outcomes can vary widely across surgical centers, but the data presented here are probably more broadly representative of the typical experience of patients having bariatric surgery in most major surgical centers in the United States,” the authors of the latest study determined. “The magnitude of the weight loss differences we observed will likely be meaningful to patients and providers as they consider treatment options for severe obesity.”