Ricerc@Sapienza

The incidence of obesity is rising worldwide and so are its comorbidities: type-2 diabetes mellitus (T2DM), dyslipidaemia, hypertension, cardiovascular disease, sleep apnoea, and depression. Bariatric/metabolic surgery has established itself over the past several years as an effective treatment not only for morbid obesity but also for its associated morbidities. The effects of bariatric/metabolic surgery on depression are controversial, with some studies showing improvement and others demonstrating a worsening.

Bariatric surgery is very effective in achieving and maintaining weight loss but it is also associated with improvement of obesity metabolic complications, primarily type 2 diabetes (T2D). Remission of T2D or at least a net improvement of glycemic control persists for at least 5 years. The bypass of duodenum and of the first portion of the jejunum up to the Treitz ligament as in Roux-en-Y Gastric Bypass (RYGB), or the bypass of the duodenum, the entire jejunum and the first tract of the ileum, such as in Bilio-Pancreatic Diversion (BPD), achieve different results on insulin sensitivity.

The gastrointestinal tract is extremely rich in endocrine cells and secretes a myriad of hormones, including ghrelin, glucagon-like peptide 1(GLP1), gastric inhibitory peptide (GIP), cholecystokinin (CCK), amylin, peptide YY (PYY), oxyntomodulin, and leptin. Mechanical distention of the stomach elicits mechanoreceptors within the gastric wall sensing tension, stretch, and volume, which then send brain signals through vagal and spinal sensory nerves.