To see whether the benefits and side effects of 2 commonly used types of bariatric surgery—gastric bypass and duodenal switch—differed over the long term in patients with severe obesity.
Who was studied?
60 people who had surgery for obesity. At the time of inclusion in the study, these patients had a body mass index between 50 and 60 kg/m2, were 20 to 50 years of age, and were relatively healthy except for their obesity.
How was the study done?
Patients were assigned by chance (“randomly assigned”) to undergo either gastric bypass surgery or duodenal switch surgery. Both procedures were done by laparoscopy.
What did the researchers find?
Two years after surgery, patients who had either type of surgery lost significant weight and had improvement in some important cardiac risk factors. People who had duodenal switch surgery lost more weight and had more improvement in cardiac risk factors. However, they also experienced more adverse events and had lower levels of some vitamins. Patients reported that their quality of life was about the same regardless of which surgery they had, although patients who had gastric bypass reported a greater improvement in pain.
What are the limitations of the study?
Only patients who were severely obese were included. They were followed only for 2 years, and it is not known whether observed benefits will continue over time. Although duodenal switch surgery resulted in more weight loss and more improvement in cardiovascular risk factors, it is not known whether these differences will lead to improved health outcomes or longer life. At the time of the study, participating surgeons had more experience in performing gastric bypass than duodenal switch.
What are the implications of the study?
Severely obese patients who are considering bariatric surgery can generally expect to see significant weight loss with either gastric bypass or duodenal switch surgery. The decision about which procedure to use needs to be individualized on the basis of a patient’s specific health status and preferences, as well as the surgeon’s experience with each procedure.