The Risks and Benefits of Weight Loss Surgery

Weight loss surgery helped to shed pounds but some patients experienced complications

/ Author:  / Reviewed by: Joseph V. Madia, MD Beth Bolt, RPh

(RxWiki News) Like any operation, weight loss surgery comes with risks and benefits. A recent review evaluated the procedure's effectiveness and possible complications.

This review examined previous trials and studies, looking specifically for deaths, surgical complications and amount of weight lost.

The researchers found that weight loss surgery was usually effective in promoting weight loss and treating weight-related diseases.

The authors of this review also noted that, while deaths from weight loss surgery were rare, many patients had surgical complications.

"Consider both benefits and risks before weight loss surgery."

Su-Hsin Chang, PhD, of the Division of Public Health Sciences at the Washington University School of Medicine, led this review of previous studies on weight loss surgery.

Severely obese people who have difficulty losing weight through lifestyle interventions sometimes choose bariatric, or weight loss, surgery. Weight loss surgery involves reducing the size of the stomach to help a patient feel fuller with less food.

This review examined the risks and benefits of weight loss surgery reported in previous trials and studies.

The researchers found 164 articles on weight loss surgery to include in the review, which included a total of 161,756 patients.

These patients were an average of 44 years old, mostly female and white.

A total of 26 percent of the participants had type 2 diabetes, 47 percent had high blood pressure, and almost 28 percent had high cholesterol.

For each study, the researchers recorded any incidences of surgical complications, death and improved obesity-related diseases. They also noted weight loss or weight gain after surgery.

Among the participants in the clinical trials, 0.08 percent died during surgery and 0.31 percent died in the month after surgery.

A total of 0.22 percent of the patients in the observational studies died during surgery and 0.35 percent died during the month following surgery.

Patients undergoing adjustable gastric band surgery, in which a band is used to create a small stomach pouch, experienced the lowest death rates.

A total of 17 percent of the patients in clinical trials and 10 percent of the patients in observational studies reported surgical complications, including bleeding, a leak and reflux.

According to the observational studies, patients lost 12 to 17 units of body mass index (BMI) in the five years after surgery. BMI is a measure of height and weight used to determine if someone is overweight, underweight or a healthy weight. 

Patients who chose gastric bypass surgery, in which a stomach pouch is formed and the small intestine is re-routed to connect to it, reduced their BMI the most.

The researchers also found that bariatric surgery was effective in treating obesity-related diseases. Between 86 and 92 percent of patients successfully treated their diabetes after surgery.

About 75 percent of participants who had high blood pressure before surgery developed normal blood pressure after surgery.

The researchers concluded that weight loss surgery typically resulted in significant weight loss with a low risk of death.

Additionally, weight loss surgery was successful in treating several patients' weight-related diseases like diabetes.

The authors of this review noted that patients should take the possible risks of weight loss surgery into account when considering the operation.

Andre F. Hall, MD, board certified obstetrician/gynecologist at Birth and Women's Care in Fayetteville, NC, said, "Bariatric or weight loss surgery encompasses a group of different types of surgery which limit the stomach's ability to accommodate food and/or create a feeling of fullness with substantially less food. These surgeries are effective in causing large amounts of weight loss over considerable less time. These surgeries should, however, be considered a last resort after an individual has truly exhausted other concentrated efforts to lose weight with diet, exercise and medications as these procedures are not without risk."

Dr. Hall continued by advising, "Among the risks are the risks of infection, bleeding, and damage to internal adjacent structures.  After the surgery, there is also a strict regimen that must be followed to prevent dehydration and nutrient deficiencies. In addition, there has to be a commitment to lifestyle change so as to avoid the circumstances that lead to the need for the surgery in the first place."

This review was published by JAMA Surgery on December 18.

The research was funded by National Cancer Institute grants and the Foundation for Barnes-Jewish Hospital. The authors disclosed no conflicts of interest.

Review Date: 
December 19, 2013
Last Updated:
December 31, 2013