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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: BACKGROUND, METHODS, RESULTS. Meshes: Adult, Female, Gastrectomy, Gastric Bypass, Gastroplasty, Humans, Male, Middle Aged, Obesity, Morbid, Postoperative Period, Preoperative Period, Time Factors, Treatment Outcome, Weight Loss.
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Is weight loss prior to bariatric surgery a pre-requisite of excess weight loss outcomes in obese patients? Context: Although weight loss before bariatric surgery may carry advantages during the surgical procedure (decreased liver volume, operation duration, and blood loss), it is still debated whether it induces a greater long-term weight loss. We conducted a retrospective analysis over 539 patients operated by the same surgeon until September 2008. Five hundred seven primary bariatric surgical procedures were performed: gastric bypass in 381, gastric banding in 97, and sleeve gastrectomy in 29. Preoperative multidisciplinary care was similar for all the patients over a period of 12 months. Relationship between weight changes during this period and the percentage of excess weight loss (%EWL) over the 48 month after surgery was analyzed by logistic regression. No relationship could be evidenced between pre- and postoperative weight loss, regardless of the surgical technique performed. Whether patients were male or female, and whether they had an initial BMI greater or lower than 50 kg/m(2), did not make a difference in the relationship between EWL at any point and weight loss prior to surgery. Despite a large range of weight changes before surgery, there was no trend for a relationship.
assistant
This study suggests that weight loss before surgery should not be considered a pre-requisite. Although it can reduce the difficulties of the surgical procedure, advantages for long-term weight loss are not validated. Final Decision: no