Gastric Bypass vs. Duodenal Switch in Patients With Severe Obesity

Bariatric Surgery May Boost Survival
Bariatric Surgery May Boost Survival
Weight loss, improvements in metabolic parameters better with duodenal switch in patients with BMIs exceeding 50.

After evaluating two types of bariatric surgery, researchers found that patients with severe obesity who underwent biliopancreatic diversion with duodenal switch experienced greater weight loss and improvements in some metabolic parameters than those who underwent gastric bypass.

Results also showed, however, that duodenal switch was associated with more surgical, nutritional and gastrointestinal adverse effects, researchers reported in JAMA Surgery.

For the study, Hilde Risstad, MD, of Oslo University Hospital in Norway, and colleagues evaluated 5-year outcomes of a clinical trial that included 60 patients aged 20 to 50 years with BMIs of 50 to 60 who were randomly assigned to gastric bypass (n=31) or duodenal switch (n=29).

Data showed that 5 years after undergoing surgery, the average reductions in BMI were 13.6 (95% CI, 11.0-16.1) with gastric bypass and 22.1 (95% CI, 19.5-24.7) with duodenal switch, with a mean between-group difference of 8.5 (95% CI, 4.9-12.2).

Although remission rates of type 2 diabetes and metabolic syndrome and changes in blood pressure (BP) and lung function were similar between groups, the researchers observed greater reductions in total cholesterol, LDL cholesterol, triglycerides and fasting glucose after duodenal switch vs. gastric bypass.

Vitamin deficiencies, however, were more prevalent 5 years after duodenal switch, with patients who underwent the procedure having significantly reduced serum concentrations of vitamin A and 25-hydroxyvitamin D, as compared with those who underwent gastric bypass.

Patients who underwent duodenal switch also experienced more adverse gastrointestinal effects, underwent more surgical procedures related to the initial procedure and had more hospital admissions than those who underwent gastric bypass, according to the study results.

In light of their findings, the researchers concluded: “We recommend that duodenal switch be used with caution owing to a higher rate of additional surgical procedures and risk of nutritional complications.”

In an invited commentary, Oliver A. Varban, MD, and Justin B. Dimick, MD, MPH, both of the University of Michigan in Ann Arbor, discussed whether the benefits of duodenal switch outweigh the considerable risks. They noted that it is difficult to recommend duodenal switch as a first-line weight loss procedure, given the adverse effects associated with the procedure.

Nevertheless, Drs. Varban and Dimick pointed out that duodenal switch should not be abandoned, but it should not be used liberally either.

“Despite its narrow role in clinical practice, duodenal switch may find a resurgence in the future as a second stage procedure for patients who have failed weight loss after sleeve gastrectomy,” they wrote.

“Sleeve gastrectomy, which is part of the duodenal switch operation, is now the most common bariatric procedure performed in many regions of the country. Many surgeons advocate revising patients with inadequate weight loss after sleeve gastrectomy to a duodenal switch. Risstad et al remind us that this strategy should only be used with great caution and only in a select group of patients with excellent follow-up and compliance.”


  1. Risstad H et al. JAMA Surg. 2015;doi:10.1001/jamasurg.2014.3579.
  2. Varban OA, Dimick JB. JAMA Surg. 2015;doi:10.1001/jamasurg.2014.3585.