Bariatric Surgery Evolution from the Malabsorptive to the Hormonal Era

Abstract

While bariatric procedures continued to evolve and develop since the 1950s, their classification has not matched this evolution. The procedures are commonly classified into restrictive, malabsorptive, or combined. In this day and age, we recognize different mechanisms of action of the bariatric procedures. This article aims to review and update the old classifications based on our current understanding of the hormonal aspects of the various bariatric procedures and the role of gut hormones in weight loss and treatment of the associated metabolic comorbidities. The article suggests the need for a new classification of the bariatric procedures, based on the mechanism of action, involving the hormonal aspects of the procedure.

IMAGING IN ENDOCRINOLOGY: The use of functional MRI to study the endocrinology of appetite

“…It is now clear that the profound and sustained weight loss achieved with this procedure is not related simply to the malabsorption of nutrients but rather to a constellation of neurohormonal effects. These include elevated post-operative levels of endogenous anorectic gut hormones such as PYY and GLP-1, increases in energy expenditure and metabolic rate, changes in taste preference away from calorie-dense foods, increased bile acid delivery to the ileum and changes in gut microbiota (65,66). Recent studies imaging appetite in patients before and after surgical weight loss are important in helping us understand some of the CNS-mediated effects, with the potential translational application of identifying those patients who would respond best to bypass surgery.…”

Changing Trends in Bariatric Surgery

“…In fact, in the animal model, when the nuclear receptor FXr of the bile acid is disrupted, the vertical sleeve gastrectomy loses its efficacy (31). the recognition of such changes and the potential ability to predict the efficacy of obesity-related disease may eventually lead to the individualization of the procedures based on the unique individual metabolic pedigree, likely based on several serologic criteria (3).…”

Role of gastrointestinal hormones in feeding behavior and obesity treatment

“…Unfortunately, the expensive cost and the complications make it impractical to treat the growing population of obese worldwide [122]. Interestingly, some studies have shown that the clinical benefits of bariatric surgery in achieving weight loss and metabolic comorbidity improvement are related to alterations in gut hormone production [123,124]. Ghrelin level after bariatric surgery showed mixed results.…”