Duodenal switch surgery leads to greater weight loss than gastric bypass, but also involves a greater risk of complications that may offset any potential benefits, according to a new study reported in a recent issue of the Annals of Internal Medicine.
Each year, in the United States, about 220,000 people undergo bariatric surgery. Gastric bypass surgery is one of the most popular procedures, while only 1% undergo the duodenal switch surgery. Other popular types of weight loss surgery are laparoscopic adjustable gastric banding and sleeve gastrectomy.
Gastric bypass and the duodenal switch both involve a restrictive and malabsorptive component to facilitate weight loss. The primary differences between the two procedures are how the stomach is resized and how much of the small intestine is bypassed. The duodenal switch is a more extreme procedure and is primarily reserved for “superobese” patients with a body mass index (BMI) of 50 or higher.
For this study, researchers set out to compare the more popular gastric bypass with the relatively rare duodenal switch surgery in areas of weight loss, cardiovascular risk factors, and quality of life. They enrolled sixty patients with a body mass index between 50 and 60 and then randomly assigned them to either gastric bypass or duodenal switch.
At the two year follow-up, fifty-eight of the sixty patients completed the study. The following outcomes were observed in the study participants:
- Weight loss was greater after duodenal switch (DS patients lost an average of 162 pounds, GB patients lost an average of 162 pounds)
- BMI reductions were greater after duodenal switch (Mean reductions of BMI was 24.8 after duodenal switch and 17.3 after gastric bypass)
- Duodenal switch led to greater reductions in total cholesterol levels and low-density lipoprotein (LDL) cholesterol levels
- Improvements in other cardiovascular risk factors and quality of life were similar between both groups
- Adverse effects were greater after duodenal switch (10 participants (32%) had adverse events after gastric bypass and 18 (62%) after duodenal switch)
- Adverse events related to malnutrition occurred only after duodenal switch
The limitations of this study include the following factors: small study size, participants were predominantly younger and female, two-year follow-up, and study centers had more clinical experience with gastric bypass than with duodenal switch surgery.
While this study highlights some of the risks and benefits associated with duodenal switch and gastric bypass, it does not take the place of a consultation with a bariatric surgeon. Both types of weight loss surgery involve risk as well as the need for follow-up and nutritional supplements for a life time.
People who are considering bariatric surgery should consider all the information but not base their decision on any one study. Rather, they should visit a bariatric surgeon to discuss the various options and then decide which procedure is best for them based on their personal health profile.