Bowel habits after gastric bypass versus the duodenal switch operation

Obes Surg. 2008 Dec;18(12):1563-6. doi: 10.1007/s11695-008-9658-9. Epub 2008 Aug 28.


Background: One of the perceived disadvantages of the biliopancreatic diversion with duodenal switch operation is diarrhea. The aim of this study was to compare the bowel habits of patients after duodenal switch operation or Roux-en-Y gastric bypass.

Methods: A prospective comparative case series design was used. Forty-six patients who underwent duodenal switch (n=28) or gastric bypass (n=18) were asked to complete a daily diary for 14 days after losing least 50% of their excess body weight. Data were collected on number of bowel episodes, incontinence, urgency, stool consistency, and awakening from sleep to defecate. Background variables were recorded from the medical files.

Results: The duodenal switch group was heavier (body mass index 53.5 vs 47.0 kg/m(2), p=0.03) and older (47.5 vs 41.0 years, p=NS) than the gastric bypass group. Median time to 50% excess body weight loss was 22 months in the duodenal switch group compared to 10.0 months in the gastric bypass group (p=0.001). Patients after duodenal switch surgery reported a median of 23.5 bowel episodes over the 14-day study period compared to 16.5 in the gastric bypass group (p=NS). There was no between-group differences in any of the other bowel parameters studied.

Conclusions: Although duodenal switch is associated with more bowel episodes than gastric bypass, the difference is not statistically significant. Bowel habits are similar in patients who achieve 50% estimated body weight loss with duodenal switch surgery or gastric bypass.

Publication types

  • Comparative Study

MeSH terms

  • Adult
  • Aged
  • Biliopancreatic Diversion* / adverse effects
  • Defecation*
  • Diarrhea / epidemiology
  • Fecal Incontinence / epidemiology*
  • Female
  • Gastric Bypass* / adverse effects
  • Humans
  • Male
  • Middle Aged
  • Obesity, Morbid / physiopathology
  • Obesity, Morbid / surgery
  • Postoperative Complications / epidemiology*
  • Prospective Studies