As obesity is rapidly increasing in the United States, so does the number of weight loss surgeries performed each year. The most popular surgical procedure for weigth loss today in the United States is gastric bypass. Second common is gastric banding. Duodenal switch and gastric sleeve are less routinely performed. A recent study, conducted in Weill Cornell College of Medicine (New York), compared the effect of the four mostly performed weight loss surgery procedures on weight loss and body fat.
The study was published in the October 2009 issue of the journal Surgery for Obesity and Related Diseases (official journal of the American Society for Bariatric Surgery).
Four groups of people were evaluated:
- 101 patients who underwent gastric bypass
- 49 patients who were subjected to biliopancreatic diversion with the duodenal switch
- 41 adjustable gastric band patients
- 30 sleeve gastrectomy patients
Which Type Of Bariatric Surgery Causes The Most Excess Weight Loss?
Researchers used the Body Mass Index (BMI = body weight / height2) of the patients as a measure of obesity. The higher the BMI the more obese a person is. The BMI before and after the bariatric surgery was significantly different in each group.
Gastric Bypass group (GB)
BMI before surgery = 46.7 kg/m2
BMI 19.1 months after surgery = 32.5 kg/m2
Biliopancreatic Diversion with the Duodenal Switch group (BPD/DS)
BMI before surgery = 53.2 kg/m2
BMI 27.5 months after surgery = 27.8 kg/m2
Adjustable Gastric Band group (AGB)
BMI before surgery = 44.3 kg/m2
BMI 21.4 months after surgery = 39.5 kg/m2
Sleeve Gastrectomy group (SG)
BMI before surgery = 61.4 kg/m2
BMI 16.7 months after surgery = 37.2 kg/m2
The above figure presents graphically the pre- and post-operative value of BMI in these four groups. In all groups the BMI decreased. As shown, the patients with the highest BMI underwent SG while those with the lowest BMI were subjected to AGB. It is obvious that the most dramatic decrease in BMI occurred in those patients who underwent BPD/DS (view source).
The figure above shows the percentage (%) of excess weight (green bar) that was lost as a result of each type of surgery. It also shows the average post operative body fat (orange bar) of people in each group. Again, it is apparent that the BPD/DS brought about the greatest excess weight loss. Moreover, patients who underwent PDB/DS had the lowest body fat at the 2-year follow-up mark (view source).
The study concluded that “although the BPD/DS procedure reduced the BMI the most effectively and promoted fat loss, all the procedures produced weight loss.”
An abstract of this study is available here