**2. History of bariatric surgery and its use in treating diabetes**

The first report of a surgical procedure aiming for weight loss is said to be the Talmud. There it is said that Rabbi Eleazor, who was morbidly obese, underwent an operation after being given a soporific potion wherein his abdomen, or abdominal wall, was opened and a number of "baskets of fat were removed" [10]. However, the first bariatric surgery intervention performed in modern time dates back to 1953, when Varco from Minessota University performed a bypass of small intestine in an obese patient, with bowel reconstruction by an jejunoileostomy [11]. This jejuno-ileal by-pass caused excellent and lasting weight loss but proved to be associated with extensive complications due to short bowel syndrome and bacterial overgrowth. In 1966, Edward Mason, who is considered the father of bariatric surgery, published the landmark paper on gastric bypass [12], while in 1977 Griffen and his colleagues performed the first gastric bypass with a Roux-en-Y gastrojejunostomy (RYGB). The popularity of this intervention rapidly rose, as it proved to be efficient and quite safe, with reduced request for revisional surgery. From the beginning of the 70's gastroplasty was introduced as an important bariatric procedure, firstly as a partial horizontal gastric transec‐ tion, than as a vertical banded gastroplasty. The following years brought into attention other innovative techniques, such as bilio pancreatic diversion (BPD), laparoscopic adjusted gastric banding (LAGB), sleeve gastrectomy (SG) or gastric plication, designed to improve the main outcome: weight loss and metabolic improvement, but also to reduce the incidence of com‐ plications.

The Greek word "baros" means weight and the term bariatric came into use in 1965, defining a branch of medicine dealing with causes, prevention, and treatment of obesity. At the beginning, interventions performed in order to obtain weight loss were mechanistically defined as purely restrictive of food intake (e.g., vertical banded gastroplasty, laparoscopic adjustable gastric banding), restrictive/malabsorptive (e.g., gastric bypass), and primarily malabsorptive (e.g.,biliopancreatic diversion/duodenal switch). It was lately clear that these anatomical descriptions did not provide the mechanism of action and the mechanical explan‐ ation of weight loss was subsequently challenged. More than that, the consequences of these procedures go far beyond weight loss, as, in addition to solving mechanical problems of gastroesophageal reflux disease, obstructive sleep apnea, and back and joint pain, they improve or even cure metabolic diseases (e.g., type 2 diabetes, hyperlipidemia, hypertension, polycystic ovary syndrome, nonalcoholic steatohepatitis, possibly cancer).

While the benefits of weight loss for obese patients with diabetes are indubitable, there are several strategies for achieving weight loss, with physical activity and intensive lifestyle modification being important components of almost all programs. The Look AHEAD Study, the largest and longest randomized controlled trial of a behavioral intervention for weight loss in patients with diabetes, showed a mean body weight reduction of 8.5% at year one; over the next four years, a gradual regaining of weight was observed, followed by the maintenance of losses of approximately 4-5% in subsequent years [8]. This quite poor maintenance of weight loss, associated with the trial's negative finding with regard to its cardiovascular endpoints [9] sustains the need, at least in some diabetic patients, for more aggressive approaches in order

The first report of a surgical procedure aiming for weight loss is said to be the Talmud. There it is said that Rabbi Eleazor, who was morbidly obese, underwent an operation after being given a soporific potion wherein his abdomen, or abdominal wall, was opened and a number of "baskets of fat were removed" [10]. However, the first bariatric surgery intervention performed in modern time dates back to 1953, when Varco from Minessota University performed a bypass of small intestine in an obese patient, with bowel reconstruction by an jejunoileostomy [11]. This jejuno-ileal by-pass caused excellent and lasting weight loss but proved to be associated with extensive complications due to short bowel syndrome and bacterial overgrowth. In 1966, Edward Mason, who is considered the father of bariatric surgery, published the landmark paper on gastric bypass [12], while in 1977 Griffen and his colleagues performed the first gastric bypass with a Roux-en-Y gastrojejunostomy (RYGB). The popularity of this intervention rapidly rose, as it proved to be efficient and quite safe, with reduced request for revisional surgery. From the beginning of the 70's gastroplasty was introduced as an important bariatric procedure, firstly as a partial horizontal gastric transec‐ tion, than as a vertical banded gastroplasty. The following years brought into attention other innovative techniques, such as bilio pancreatic diversion (BPD), laparoscopic adjusted gastric banding (LAGB), sleeve gastrectomy (SG) or gastric plication, designed to improve the main outcome: weight loss and metabolic improvement, but also to reduce the incidence of com‐

The Greek word "baros" means weight and the term bariatric came into use in 1965, defining a branch of medicine dealing with causes, prevention, and treatment of obesity. At the beginning, interventions performed in order to obtain weight loss were mechanistically defined as purely restrictive of food intake (e.g., vertical banded gastroplasty, laparoscopic adjustable gastric banding), restrictive/malabsorptive (e.g., gastric bypass), and primarily malabsorptive (e.g.,biliopancreatic diversion/duodenal switch). It was lately clear that these anatomical descriptions did not provide the mechanism of action and the mechanical explan‐ ation of weight loss was subsequently challenged. More than that, the consequences of these procedures go far beyond weight loss, as, in addition to solving mechanical problems of gastroesophageal reflux disease, obstructive sleep apnea, and back and joint pain, they

**2. History of bariatric surgery and its use in treating diabetes**

to obtain substantial and durable weight loss.

196 Treatment of Type 2 Diabetes

plications.

Metabolic surgery was defined in 1978 by Henry Buchwald and Richard Varco as "the operative manipulation of a normal organ or organ system to achieve a biological result for a potential health gain" [13]. The practice of metabolic surgery goes, however, way before this timeline; examples are the procedures of gastrectomy or vagotomy for duodenal ulcers, procedures that don't touch the actual lesion, or splenectomy for idiopathic thrombocytopenic purpura. In the late 80's, The Program on the Surgical Control of the Hyperlipidemias (POSCH) showed that a surgical procedure (partial ileal by-pass) could dramatically improve total cholesterol and low-density lipoprotein cholesterol levels, as well as atherosclerotic coronary heart disease mortality and recurrent nonfatal myocardial infarction as well as overall mortality, the incidence of coronary artery bypass grafting and percutaneous transluminal coronary angioplasty, and the development of peripheral vascular disease [14].

Nicola Scopinaro and Walter Pories were among the first who stated the effectiveness of gastrointestinal surgery procedures in correcting or even curing type 2 diabetes; they showed normalization of blood glucose levels after biliopancreatic diversion [15] and gastric by-pass, respectively [16]. In a milestone publication entitled "*Who would have thought it? An operation proves to be the most effective therapy for adult-onset diabetes mellitus",* Pories underlined the importance of hormonal mechanisms in the process of improving or even curing type 2 diabetes mellitus, independent of weight loss. Bariatric surgery is beyond doubt metabolic surgery, as it causes dramatic improvement of type 2 diabetes and can effectively prevent progression from impaired glucose tolerance to diabetes in severely obese individuals, but it also resolves or mitigates some other important complications of obesity, such as dyslipidemia, hypertension, insulin resistance, sleep apnea [17].
