Comments regarding a recent article comparing gastric bypass and duodenal switch and its questionable method and results
Department of Surgery, Institut Universitaire de Cardiologie et de Pneumologie de Québec, Quebec, Quebec, Canada
published online 02 December 2011.
Last September a group from Norway and Sweden reported in the Annals of Internal Medicine a clinical randomized trial comparing Roux-en-Y gastric bypass and duodenal switch (DS) . This report was accompanied by an editorial by Livingston  from the University of Texas. The report is remarkable for its presentation, and these investigators are to be congratulated for their courage in undertaking a pioneering task. However, we would like to express our reservation concerning both the use of randomization in this context and, in particular, the view presented in the accompanying editorial, which limits the role of bariatric surgery to saving lives.
The study compares 2 operations known to differ by their mechanisms of action ,  and their long-term results , , . Also, their complications are known to be related to surgeon experience and the quality of follow-up. More emphasis should have been given to these 2 variables and to the definition of success .
Because risk is dependent on many factors, which are better evaluated by an expert than by the patient, we question how the patients’ desire “to lose as much weight as possible,” which is true for most patients, was evaluated and taken into consideration, along with the perceived risk of surgery versus the risk of persistent morbid obesity with its associated, but preventable, weight-related complications.
Randomization in bariatric surgery is difficult to achieve and could even be harmful . The evaluation of both the risk and the goal belongs to the patient; however, the risk is very dependent on the surgeon’s experience. Randomization might be possible in comparing different techniques with “marginally” differing results, but it should not be done only to fulfill the requisite for randomization itself at all costs, believing it to represent the unique essential scientific approach.
As it was expected, even within 2 years, their results showed that DS resulted in better weight loss that was expected to increase over the years. At the nadir weight, morbid obesity was not cured for a large percentage of patients after Roux-en-Y gastric bypass. Of these patients, 30% were still morbidly obese, if defined by a body mass index >40 kg/m2, and 60%, if defined by a body mass index >35 kg/m2. Furthermore, was the advantage of DS in changing the metabolism, representing a lifelong advantage for both preventing recurrent long-term weight regain and excess fat absorption, really addressed with the patients? Morbid obesity is a metabolic disease involving insulin resistance transmitted from generation to generation, and DS is more efficient in reducing insulin resistance , . Was this also explained to the patients?
In the accompanying editorial, Livingston seems to underestimate that an improving quality of life remained the primary objective sought by these patients . Often, they express themselves in stating their desire to lose as much weight as possible even at a reasonably greater risk. Their desire results from the fact that the relief of co-morbidities is directly related to the amount of weight lost .
The content of this editorial represents a return to the early days of bariatric surgery when there was an obvious discordance between patients’ goals and the surgeons’ goal of defending their own disappointing results . Such a stance is rarely taken today by those with a long experience in bariatric surgery. In his comment, Livingston questions whether surgery is worth performing. It is his patients who are no longer morbidly obese to whom he should pose the question. They themselves will be able to balance between curable complications or side effects with the advantage of no longer being morbidly obese.
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