While the gastric band is considered a comparatively gentle and reversible operation, duodenal-switch and Y-Roux-Bypass are not that easy to reverse. The surgeon changes the entire architecture of the upper intestinal tract with the target that ingested food is digested less effectively and accordingly less extensively reabsorbed.
Bariatric operations: Metabolically successful, but not undisputed
Especially with duodenal-switch and Y-Roux-Bypass, the results of the bariatric approach are quite impressive. Professor Rudolf Weiner at the Sachsenhausen hospital recently reported about a group of 284 patients with an average BMI of 55, all of them undergoing a bariatric surgery.
Completely aside from the known significant effects on the body weight, Weiner observed also considerable metabolic consequences: “The rate of hypertonics was cut to half and diabetics were reduced to one third”, says Weiner. And the fat content of the liver as well changed dramatically. While at the time of the surgery nearly all patients suffered from a histologically proven steatohepatitis, only 18 months later only 12 percent of the patients with Y-Roux-Bypass still had that problem and none of the ones with a duodenal-switch. Only with the gastric band, the results were not that significant. Despite this data, bariatric surgery has numerous critics. They point out a debatable long-term effectiveness, uncertain long-term consequences in the intestines as well as potential psychological consequences such as depressions. So it doesn’t come as a surprise that physicians and researchers were and are looking for reversible approaches, reversible like the gastric band but preferably as effective as the Y-Roux-Bypass. The so-called EndoBarrier is a procedure claiming exactly that, a medical device tested mainly in the Netherlands here in Europe for the past few years. Originally the approach was to treat patients suffering from a severe obesity prior to surgeries in order to reduce the weight by acceleration to decrease the risk. But now the European authorities have approved of the application for up to twelve months for patients with severe obesity and diabetes type-2.
Ingestion mild to the villi
EndoBarrier is manufactured by the US-company GI Dynamics. Casually speaking we are talking about a plastic tube, a sleeve introduced through the mouth into the digestion system of the obese person with an endoscope. The upper end of the tube is placed and fixed at the entrance to the duodenum. Now the about one meter tube gets unwinded for the food to pass this part of the intestine without touching its walls any more. Only at the end of the tube, the partly digested food meets again with new digestion enzymes. Actually the principle is quite similar to the Y-Roux-Bypass which also involves that food does not get from the stomach into the duodenum first but continuously flows distally. The University Hospital Maastricht has published three short videos in the internet illustrating the surgery graphically.
Interesting approach, but what about hard facts and data? The manufacturer talks about clinical studies with more than 300 patients. Published was this year a randomized study within the above pre-surgical context in the Annals of Surgery with 41 patients, 30 of them received the intestinal tube for three months. Eleven served as a control group. In the intervention group, the BMI decreased by 19 percent within three months compared to seven percent in the control group. In seven of eight patients with type-2 diabetes, the metabolic parameters improved. But all patients showed – mainly in the week before the surgery – undesired side effects such as nausea and pain. The tube had to be removed ahead of schedule from four patients due to dislocation or obstructions.
Lowering the cholesterol and the HbA1c
New data was available at this year’s Congress of the IFSO in Los Angeles/USA. 24 people with overweight and an average BMI of 45 were provided with an EndoBarrier for one year. No control group this time. In this case, the BMI went down by an average of 20 percent. Cardio-metabolically the total cholesterol decreased from 196.5 to 161 mg/dl and the diastolic blood pressure from 84.8 to 71.2 mmHg. An additional study, introduced by the Digestive Disease Week 2010, found a positive effect on HbA1c in diabetic patients. Both studies were not fully published yet. A randomized multicenter-study with Sham-endoscopy not blinded by the physicians in another pre-surgical context was published in the magazine Gastrointestinal Endoscopy. The effect on the weight was similar to the other studies. The tube had to be removed prior to the twelve weeks study phase from 8 out of 21 patients.