Study Finds Weight Loss Surgeries Increase Risk of Gastrointestinal Complications

Two different types of weight loss surgery have been linked to an increased risk of serious gastrointestinal complications, nutritional disorders, and even alcohol dependence, according to the findings of new research. 

In a study published in the medical journal The Lancet Diabetes & Endocrinology, French researchers indicate individuals who underwent gastric bypass or sleeve gastrectomy face a higher risk of gastrointestinal (GI) complications, such as GI disorders and endoscopy, as well as an increased risk of developing alcohol dependence following the weight-loss surgery.

During gastric bypass surgery the stomach is reduced to the size of an egg by rerouting the intestine and splitting the stomach into two pouches. During sleeve gastrectomy the stomach is reduced to 15% of its original size by removing the rest of the stomach.

Researchers used data from the French National Health Insurance database to find patients who either underwent gastric bypass or sleeve gastrectomy surgery in France in 2009. Nearly 9,000 patients who had primary gastric bypass and 4,000 patients who had sleeve gastrectomy were compared to a control group matched in age, sex and obesity levels. Patients were followed for six to eight years.

According to the findings, patients who underwent either type of bariatric surgery faced a higher risk of side effects and hospital admission for adverse events. However, gastric bypass patients had a higher risk of side effects overall than sleeve gastrectomy patients. Yet, both surgeries increased a person’s risk of needing invasive gastrointestinal surgery, endoscopy, experiencing GI disorders, and suffering nutritional disorders.

Research published last year also indicated gastric bypass patients face higher risks of complications such as higher rates of death and deep vein thrombosis compared to patients having other surgeries like gastric sleeve or lap band.

The most common events after gastric bypass surgery were gastroesophogeal reflux disease, gastritis, and other upper gastrointestinal symptoms. The most common event for sleeve gastrectomy was small bowel obstruction.

A study published in 2017 indicated some types of gastric bypass surgery increased the likelihood patients would suffer indigestion and food intolerances, as well as other digestive tract problems.

Despite these risks, undergoing gastric bypass surgery reduced a patient’s risk of death by 36% compared to obese patients in the control group. Furthermore, undergoing sleeve gastrectomy reduced a patients risk of early death by 62% compared to obese controls.

Both surgeries helped to extend the lifespan for obese patients, but posed other risks and side effects.

Patients who underwent both surgeries also had a slightly higher risk for alcohol dependence. Another study published in 2012 also indicated gastric bypass surgery increased a patient’s risk of substance abuse and alcohol addiction.

Conversely, the new study noted psychological health appeared unaffected by either type of bariatric surgery There was no increase in psychiatric disorders after bypass or sleeve gastrectomy and no increase in postoperative suicide. This finding differs from other studies that have shown bariatric surgery may increase a patient’s risk of suicide and self-harm.

“Despite lower 7-year mortality, patients undergoing gastric bypass or sleeve gastrectomy had higher risk of hospital admission at least once for late adverse events, except for psychiatric disorders, than did control patients, with a higher risk observed after gastric bypass than with sleeve gastrectomy,” the researchers concluded.