MANAGEMENT OF ENDOCRINE DISEASE: Which metabolic procedure? Comparing outcomes in sleeve gastrectomy and Roux-en Y gastric bypass

in European Journal of Endocrinology
View More View Less
  • 1 Department of General, Visceral, and Transplantation Surgery, University of Heidelberg, Heidelberg, Germany

Free access

Obesity and its associated comorbidities have become one of the largest challenges for health care in the near future. Conservative therapy for obesity and related comorbidities has a very high failure rate and poor long-term results. Similarly, the conservative and medical management of the majority of metabolic diseases such as type 2 diabetes mellitus are only able to slow down disease progression but have no causal effect on the disease process. Obesity surgery has evolved as a highly effective therapy for severe obesity achieving long-lasting weight loss. Furthermore, several studies have demonstrated the beneficial effects of obesity surgery on reduction of overall mortality, reduction of cardiovascular events and superior control of obesity-related diseases such as type 2 diabetes mellitus, dyslipidemia and also the non-alcoholic steatohepatitis compared to medical therapy. Based on these findings, the term ‘metabolic surgery’ with the focus on treating metabolic diseases independent of body weight has been coined. Of great interest are recent studies that show that even existing complications of metabolic diseases such as diabetic nephropathy or the non-alcoholic steatohepatitis can be reversed by metabolic surgery. Although metabolic surgery has proven to be a safe and effective treatment for obesity, resolution of comorbidities and enhancing quality of life, it is still uncertain and unclear, which surgical procedure is the most effective to achieve these metabolic effects. The aim of this review is to compare the effects of the two currently most widely used metabolic operations, the Roux-en-Y gastric bypass and the sleeve gastrectomy in the treatment of obesity and its related comorbidities.

Abstract

Obesity and its associated comorbidities have become one of the largest challenges for health care in the near future. Conservative therapy for obesity and related comorbidities has a very high failure rate and poor long-term results. Similarly, the conservative and medical management of the majority of metabolic diseases such as type 2 diabetes mellitus are only able to slow down disease progression but have no causal effect on the disease process. Obesity surgery has evolved as a highly effective therapy for severe obesity achieving long-lasting weight loss. Furthermore, several studies have demonstrated the beneficial effects of obesity surgery on reduction of overall mortality, reduction of cardiovascular events and superior control of obesity-related diseases such as type 2 diabetes mellitus, dyslipidemia and also the non-alcoholic steatohepatitis compared to medical therapy. Based on these findings, the term ‘metabolic surgery’ with the focus on treating metabolic diseases independent of body weight has been coined. Of great interest are recent studies that show that even existing complications of metabolic diseases such as diabetic nephropathy or the non-alcoholic steatohepatitis can be reversed by metabolic surgery. Although metabolic surgery has proven to be a safe and effective treatment for obesity, resolution of comorbidities and enhancing quality of life, it is still uncertain and unclear, which surgical procedure is the most effective to achieve these metabolic effects. The aim of this review is to compare the effects of the two currently most widely used metabolic operations, the Roux-en-Y gastric bypass and the sleeve gastrectomy in the treatment of obesity and its related comorbidities.

Invited Author’s profile

Beat Müller-Stich has been chief of the Minimally Invasive and Metabolic Surgery since 2010 at the University of Heidelberg and became a senior attending surgeon in 2012. His research focus is on metabolic surgery and minimally invasive oncological surgery. The main area of research in metabolic surgery is the treatment of type 2 diabetes and non-alcoholic fatty liver disease with metabolic surgery and other obesity-related disease. Clinical studies consist of large multi-center trials and also translational research including the investigation of the mechanisms by which metabolic surgery improves obesity and diabetes-related mechanisms.

Introduction

During the last decades, obesity has become a worldwide epidemic and is one of the largest challenges for health care in the near future (1, 2). Obesity itself but especially obesity-associated diseases such as type 2 diabetes (T2DM), cardiovascular diseases, non-alcoholic fatty liver disease (NAFLD) along with steatohepatitis (NASH) and renal failure are strongly increasing and are responsible for a large amount of the current and future health care spending (2, 3, 4, 5, 6, 7, 8, 9, 10, 11). Conservative treatment options for obesity and its comorbidities suffer from a high failure rate and are limited to slowing down disease progression without an impact on the cause of the disease (1, 12, 13, 14). Weight loss with lifestyle change is usually limited to 10% body weight in the short term while after 1 year, the failure rate, i.e. weight regain and often even the gain of additional weight occurs in >95% of patients (15). The treatment of diabetes aims to control blood sugar levels although there is clear evidence that tight blood sugar control with insulin does not affect overall and cardiovascular-related mortality or the progression of kidney disease to renal failure (16). Also, lifestyle interventions do not reduce cardiovascular events despite weight loss and improved glycemic control (17). The real-world value of newly developed antidiabetic medication such as glucagon-like protein (GLP-1) agonists, the dipeptidyl peptidase-4 inhibitors or sodium/glucose cotransporter 2-blockers, which have shown some promise in at least some subgroups of diabetic patients, still needs to be determined (18, 19, 20). Regarding NAFLD, and in particular NASH, the mainstay of therapy remains lifestyle changes since no effective medical treatment has yet been introduced (3, 21, 22, 23). Currently, there are several on-going studies on this topic and will show whether these newly developed drugs will provide an effective therapy option for NAFLD/NASH (22, 23). As of now, medical therapy for obesity and its related comorbidities is still largely supportive, ineffective and has little effect on severe complications such as the development of cardiovascular events, kidney failure, dyslipidemia or progression of NAFLD/NASH to liver cirrhosis or hepatocellular carcinoma (HCC) (12, 16, 17).

In contrast, obesity surgery has been shown to achieve sustained weight loss over decades in many patients while also effectively treating obesity-associated diseases. Due to these strong effects on obesity-associated diseases, the focus for indications for obesity surgery is shifting toward comorbidities and away from weight or BMI-based indications. The work by Sharma et al. clearly showed that the obesity-related comorbidities are more relevant for the long-term survival than the BMI (24, 25). The concept of metabolic surgery is of high relevance since conservative, multimodal therapy does not impact survival and cardiovascular events, even when the surrogate parameters such as HbA1c, weight and waist circumference are improved, as has been shown in the LookAHEAD trial (17). These findings from non-operative therapy of metabolic diseases are strongly contrasted by the data from metabolic surgery. The data from the Swedish obese subject (SOS) study as well as from the United States show that obesity surgery results in a long-lasting weight loss over 12 years and more in severely obese patients with a BMI > 35 kg/m2 (26, 27, 28, 29). Often accompanied is a remission of T2DM in 20–80% of patients, an important improvement and possible remission of dyslipidemia, as well as cardiovascular disease-related mortality (26). Furthermore, data from the SOS study and other publications showed a significantly reduced incidence of diabetes-associated microvascular complications but also macrovascular complications in general during a mean follow-up time of 17.6 years (28, 29, 30, 31). Regarding T2DM, there is ample high-class evidence from randomized controlled trials (RCTs) that suggest that obesity surgery, and in particular the Roux-Y gastric bypass (RYGB) and sleeve gastrectomy (SG), achieve superior control of T2DM and metabolic syndrome, including dyslipidemia compared to even very intensive lifestyle changes and optimal medical therapy (32, 33, 34, 35, 36, 37). A recent meta-analysis using only RCTs confirms that obesity surgery achieves superior diabetes remission and resolution of the metabolic syndrome than lifestyle intervention and medical therapy in patients with a BMI >27 kg/m2 (38). Another meta-analysis has also concluded that obesity surgery even in nonseverely obese patients with a BMI of 25–35 kg/m2 is superior to medical and lifestyle interventions (39). Therefore, it is nowadays justified to refer to obesity surgery as metabolic surgery. And even more importantly, metabolic operations can also improve an already existing diabetic nephropathy at the time of the operation (30, 40, 41, 42, 43). Additionally, some studies from our group along with other publications indicate that metabolic surgery improves not only diabetic nephro- and neuropathy, but also retinopathy (42, 44, 45, 46, 47, 48). Thus far, sustained remission and improvement of existing microvascular complications cannot be achieved with medical therapy.

Lastly, obesity surgery is also highly effective in treating NAFLD and NASH resolving the histological features in the majority of patients, even in advanced NASH fibrosis (49, 50).

Although bariatric surgery has proven to be a safe and effective treatment for obesity, resolution of comorbidities and enhancing quality of life, to date, it is still uncertain and unclear, which surgical procedure is the most effective to achieve these metabolic effects. The aim of this review is to compare the effects of the two currently most widely used metabolic operations, the RYGB and SG in the treatment of obesity, but especially on the effects of T2DM, dyslipidemia and NAFLD/NASH.

Overview of surgical procedures for obesity and metabolic disease

Obesity surgery is not a new field as it has been around for over four decades, but it has become widely used to treat obesity and its associated comorbidities in the last two decades (1). It has traditionally been divided into restrictive procedures and a combination of restrictive and malabsorptive procedures (51). Laparoscopic gastric plication, laparoscopic adjustable gastric band (LAGB) and laparoscopic SG could be considered restrictive procedures, although there are many additional metabolic effects, which go beyond the effects of pure restriction of food intake. This is especially true for the SG, which has well-described changes in intestinal hormones, bile acid metabolism, microbioma and the gut–brain signaling (52, 53). The RYGB has a small gastric pouch and bypasses the stomach, duodenum and first part of the jejunum. The malabsorptive effects of the RYGB however are limited (54). The biliopancreatic diversion (BPD) in contrast, is mainly a malabsorptive procedure with only about 100 cm of common channel for resorption of food.

Currently, RYGB and SG are the most commonly performed bariatric procedures in the last decade (55). According to the International Federation for the Surgery of Obesity and Metabolic Disorders (IFSO) registry report 2017, there were 89,662 bariatric surgeries reported worldwide between 2013 and 2017. Of those, 46.3% (41,508) were RYGB, while 43.6% (39,137) were SG (55, 56). The popularity of the LAGB, which used to be the most frequently used bariatric procedure in the first decade of the 2000s, has drastically decreased in recent years due to the unfavorable safety profile in the long-term and the poor long-term weight loss in comparison with the other bariatric procedures (57, 58, 59). Throughout the years, both surgeries have been demonstrated to be safe and effective for the treatment of obesity (60, 61, 62, 63).

Mechanisms of metabolic surgery

The mechanisms by which metabolic operations affect metabolism are still poorly understood. Food restriction and weight loss is certainly an important part for the beneficial effects of metabolic procedures as demonstrated by the effects of the LAGB, the only purely restrictive bariatric procedure, which also achieves significant weight loss and remission of T2DM (64, 65). Furthermore, some of the effects of metabolic procedures on T2DM can be mimicked by a very-low-calorie diet in the very short term for about 6 months (66, 67, 68). However, the recurrence rate of T2DM after an initial very-low-calorie diet of 8 weeks followed by a stepwise return to an isocaloric diet was >60% after 6 months (66). Although these findings are important and help to shed light on the mechanisms of metabolic surgery, there is ample evidence that food restriction plays a lesser role than initially expected (69, 70). In line with these findings are recent studies showing that the fibroblast growth factor, a hormone that is relevant for energy consumption and mitochondrial function and the hypothalamic–adrenal axis is very differently affected by metabolic surgery than very-low-calorie diets (71, 72). Further supporting the role of hormonal changes after metabolic surgery is the fact that the LAGB is clearly inferior to both SG and RYGB regarding long-term weight loss and T2DM remission (73, 74). These findings are further supported the study of Purnell et al., which showed that the chances for T2DM remission after RYGB is significantly higher for any given weight loss compared to LAGB (75). Several theories about the hormonal changes are intensively under investigation but none of them currently stand out as the leading mechanism. Early studies found that gastrointestinal hormones such as GLP-1, ghrelin, peptide-YY (PYY) and others are affected by metabolic surgery. RGYB as well as SG induce similar changes in these hormones expect for ghrelin (76, 77, 78, 79, 80). Ghrelin is reduced after SG due to the resection of large parts of the stomach, whereas ghrelin may increase or remain stable after RYGB. Other mechanisms of action are the changes in bile acid metabolism and signaling, changes in the microbioma as well as changes in food perception and appetite (52, 76, 81, 82). For a detailed review of the current understanding of the mechanisms of metabolic surgery, we refer to current specific reviews on this topic (76).

Roux-en-Y gastric bypass

RYGB (Fig. 1A) is one of the most common bariatric surgeries performed worldwide. In the mid 1960s, Edward Mason described the first experience with open gastric bypass surgery for weight loss (83). In response to the gastric bypass, less complicated gastric restrictive procedures were developed in the 70s, and these procedures were known as ‘gastroplasties’. In the mid-90s, the first laparoscopic RYGB was first successfully performed laparoscopically by Alan Wittegrove (84). The success of laparoscopic surgery in other procedures led to the widespread adaption of laparoscopic surgery also in obesity surgery resulting in significantly reduced complications and therefore increased acceptability of obesity surgery (85). In the current form of the RYGB (Fig. 1A), a gastric sleeve pouch is created of approximately 20–30 mL volume using a 36–42 French bougie with an alimentary limb of approximately 120–150 cm in length and a biliary limb of approximately 50–100 cm in length, depending on the individual technique (86). Both gastro-jejunal and jejuno-jenunal anastomosis can be created using stapler devices and sutures. There is currently an on-going debate about the ideal limb length for the Roux- as well as the biliopancreatic limb (87, 88). Some studies have shown that a longer biliopancreatic limb length results in improved weight loss and better T2DM remission (89). However, the most currently presented data of a high-quality RCT with a 150 cm biliopancreatic limb and 75 cm Roux-limb only showed a trend toward better weight loss after 4 years, whereas diabetes remission was not different (Berends et al. IFSO 2017 (90)). However, the lengthening of the Roux-limb to achieve a short common channel of 75–100 cm (distal RYGB) as a primary operation is associated with a high risk of malnutrition as well as vitamin and micronutrient deficiency and is therefore reserved for re-do operations after failed conventional RYGB (91, 92, 93, 94).

Figure 1
Figure 1

(A) Classic Roux-Y gastric bypass. (B) One-anastomosis gastric bypass.

Citation: European Journal of Endocrinology 179, 2; 10.1530/EJE-18-0009

An adaption of the classic RYGB is the one-anastomosis or mini-gastric bypass (OAGB, Fig. 1B) in which a long gastric pouch is formed similar to SG without pylorus, but the biliopancreatic limb is not divided and anastomosed to the gastric pouch about 150–200 cm distal from the ligament of Treitz (Fig. 1B). The second anastomosis of the jejunum to the ileum is not necessary. There are only few studies comparing the classic RGYB with the OAGB and the data quality is generally poor. In uncontrolled, retrospective data, the OAGB seems superior in regard to weight loss and diabetes remission, but the only RCT showed no significant difference (87, 88, 89). However, the nutritional complications regarding malnutrition as well as vitamin and micronutrient deficiency are also higher after OAGB, and it remains to be seen whether the OAGB will become a widely used operation (95).

Sleeve gastrectomy

In the last decades, SG has increased its popularity around the world (Fig. 2). Based on Nicola Scopinaro´s BPD, Douglas Hess performed a BPD with a duodenal switch (BPD/DS) combined with a tubular stomach (gastric sleeve) instead of the typical 2/3 gastrectomy (96). Since the BPD-DS as well as the RYGB are technically very difficult to perform in super-obese patients with a BMI > 60 kg/m2, the concept of two-stage procedures was introduced (97, 98, 99, 100, 101). In this approach, the first step was the SG and after an initial weight loss, the second step with BPD was performed. However, some patients already experienced an extensive weight loss with the SG and the second-stage operation was not necessary anymore resulting in the description of the SG as a stand-alone procedure for weight loss (97, 98, 102). In the SG, an estimate of 75–85% of the stomach is excised by dissecting the greater curvature using linear staples to create a gastric tube. SG has emerged as one of the top surgical treatment options with excellent weight loss, minimal morbidity and negligible mortality (103, 104). Also, the risk for malnutrition or vitamin and micronutrient deficiency is minimal (105, 106, 107).

Figure 2
Figure 2

Sleeve gastrectomy.

Citation: European Journal of Endocrinology 179, 2; 10.1530/EJE-18-0009

Short- and long-term weight loss after metabolic surgery

Both surgeries are known to have good short- and long-term results regarding weight loss. Many studies have published short-term results after 2–3 years and a systematic review found no difference in median weight loss (108). Two high-quality RCTs were performed comparing RYGB with SG showing no clinically relevant difference between SG and RYGB 5 years postoperatively even though the difference was statistically different with 3.6 kg weight loss difference in the study by Peterli et al. (60, 63). There is a limited amount of studies reporting long-term results (>5 years) after SG (Table 1). Noel et al. performed a study to present long-term weight loss results after SG (109). A percentage excess weight loss (%EWL) of 76% at 5 years and 67% at 8 years was reported. They concluded that after 8 years, SG remains as a favorable treatment for obesity. Another study by Sarela et al. analyzed results at 8–9 years after SG, in which 55% of their patients had a %EWL of >50% (110). Regarding RYGB, Mehaffey et al. analyzed 316 patients at 10 years after RYGB, with favorable results of percentage excess body mass index lost (%EBMIL) of 52.7% (111). With these results, they concluded that RYGB remains an excellent and durable operation for long-term weight loss. Obeid et al. reported similar results 10 years after RYGB with a %EWL of 58.9% (112). In summary, there may be some benefit for more weight loss after RYGB, but the difference is minimal (in the range of 1–2 BMI-points) and clinically most likely not relevant. In 2015, the BariSurg trial was started to investigate EWL rates 2 years after either RYGB or SG (113). As a secondary endpoint, EWL rates 60 months after surgery will be analyzed. The recruitment period is currently ongoing.

Table 1

Effect of RYGB and SG on weight loss.

ReferenceFollow-up (years)RYGBSG
(111)568.8 %EBMILn/a
1052.7 %EBMILn/a
(112)1070.7 %EBMILn/a
(146)1063.3 %EBMILn/a
(186)1069.0 %EWLn/a
(187)1057.1 %EWLn/a
(63)568.3 %EBMIL61.1 %EBMIL
(60)557.0 %EWL49.0 %EWL
(62)567.8 %EWL60.2 %EWL
(110)>8n/a69.0 %EWL
(188)11n/a62.5 %EWL
(136)8n/a46.0 %EWL
(137)6n/a67.3 %EWL
(138)5n/a62.9 %EWL

%EBMIL, percentage excess body mass index loss; %EWL, percentage excess weight loss; n/a, information not available; RYGB, Roux-en-Y gastric bypass; SG, sleeve gastrectomy.

T2DM remission and glycemic control after metabolic surgery

Metabolic surgery is the best therapy for T2DM in patients with a BMI >25 kg/m2 achieving superior glycemic control compared to even very intensive lifestyle modification and optimal medical therapy. Besides superior glycemic control, metabolic surgery also reduces the incidence of microvascular complications and can improve preexisting diabetic nephropathy. Ultimately, metabolic operations reduce mortality in patients with obesity, especially in patients with T2DM (114, 115). Despite the clear evidence that metabolic surgery is superior to conservative therapy, it remains unclear, which procedure achieves better T2DM-related outcomes. Depending on the quality of data, the results are different. A recent meta-analysis by Li et al., which included all published studies independent of the study quality, found that RYGB achieves more T2DM remission than SG (116). However, when only RCTs are included in the meta-analysis, there are no differences regarding T2DM remission (117). However, the RCT with the longest follow-up, the STAMPEDE-Trial by Schauer et al., found that patients after RYGB need less antidiabetic medication after 5 years compared to SG (118). Glycemic control on the other hand is similar between groups. An overview of the mid-to-long-term results of high-quality studies are shown in Table 2. To better select the ideal patient for RYGB or SG, the patients, enrolled in the future, need to be better classified in terms of their endocrine pancreatic function and insulin resistance as well as the effect of each procedure on these parameters. Aminian et al. proposes a score (individualized metabolic surgery score (IMSS)) to assess chances of T2DM remission and to select the appropriate procedure (119). The IMSS is based on the STAMPEDE study and was validated in a cohort of Spanish patients. It includes number of preoperative medication, preoperative insulin use, T2DM duration and preoperative HbA1c <7%. Based on these points, T2DM can be divided into three stages and RYGB is suggested for mild disease although SG can also be used since likelihood of complete T2DM remission is high (119). In the intermediate stage, the authors recommend RYGB since more patients are off any anti-diabetes medication after RYGB than SG. In a severe stage, the authors recommend SG since chances for T2DM remission are slim in both procedures and SG is safer and has fewer complications. Another study on prediction of T2DM remission also found that RYGB is associated with slightly better rates of T2DM remission than SG, although other parameters such as insulin use and duration of T2DM play a much stronger role than the type of operation (120). It is very clear however that preoperative BMI is irrelevant whether a metabolic operation achieves T2DM remission or not. Panunzi et al. showed that T2DM remission was similar when considering a BMI >35 kg/m2 or a BMI of <35 kg/m2 with 71% and 72%, respectively (121).

Table 2

Effect of RYGB and SG on glycemic control.

ReferenceSurgeryPre-OP HbA1C (%)Post-OP HbA1C (%)Follow-up (years)
(33)RYGB8.7 ± 1.46.7 ± 0.55
(32)RYGB9.3 ± 1.47.3 ± 1.55
SG9.5 ± 1.77.4 ± 1.65
(60)RYGB7.8 (7.2–8.5)* 6.6 (6.4–6.8)* 5
SG7.5 (6.9–8.1)* 6.6 (6.4–6.8)* 5
(63)RYGB7.2 (6.4–8.0)5.9 (5.7–6.1)5
SG7.6 (6.8–8.4)6.2 (5.9–6.6)5
(34)RYGB9.6 ± 1.06.7 ± 2.03
(37)RYGB8.57.13
(189)RYGB/SG7.5 ± 1.85.7 ± 1.1>1
(190)RYGB7.7 ± 1.36.2 ± 0.51
SG8.3 ± 1.85.9 ± 0.91
(191)RYGB6.3 ± 0.95.5 ± 0.51
SG6.4 ± 1.35.5 ± 0.41
(192)RYGB10.4 ± 1.15.9 ± 0.31

HbA1c, glycated hemoglobin; post-OP, postoperative; pre-OP, preoperative; RYGB, Roux-en-Y gastric bypass; SG, sleeve gastrectomy; *Values provided as mmol/L

NAFLD/NASH improvement after metabolic surgery

NAFLD and NASH are recognized as a rapidly increasing challenge since they are associated with many other metabolic diseases including T2DM and dyslipidemia (3, 5, 122, 123). Furthermore, the progression of NASH to liver cirrhosis and ultimately liver failure requiring transplantation is projected to become the most common indication for liver transplantation in the near future (21, 124, 125, 126). The development of HCC directly from NASH without liver cirrhosis appears to be an additional feature of NASH, which requires new surveillance strategies (3, 124, 127). Data from the University of Lille bariatric cohort have clearly demonstrated that metabolic surgery is able to effectively treat NAFLD and NASH while also improving liver fibrosis (49, 50). Epidemiologic data suggest that bariatric operations also reduce the incidence of HCC compared to matched patients who did not undergo such an operation (27, 128). However, there are only few studies comparing the effects of different metabolic operations on NAFLD/NASH and the data are conflicting (Table 3). We have previously reported that in obese patients with T2DM, SG normalizes liver function tests after 12 months, whereas RYGB was not able to achieve normal transaminases (129). These findings are supported by a recent RCT, which also found that SG normalizes liver function tests within 12 months after surgery but not RYGB (130). In contrast to these findings, a very recent analysis from our cohort of all bariatric patients found that the liver stiffness may be better improved by RYGB than SG (131). The main issue with all these studies is that they did not have liver biopsies during the follow-up but only surrogate markers such as transaminases or liver stiffness. Future studies will be necessary to determine whether RYGB or SG have an advantage regarding improvement of NAFLD/NASH. What is clear however is that the gastric band is inferior to RYGB (132).

Table 3

Effect of RYGB and SG on NAFLD/NASH.

Reference SurgeryALT, U/L AST, U/L
Pre-OPAt 12 monthsPre-OPAt 12 months
(130)RYGB35.1 ± 14.132.0 ± 19.323.6 ± 7.721.4 ± 6.4
SG27.8 ± 19.921.7 ± 12.923.7 ± 12.822.5 ± 7.2
(131)RYGB/SG42.3 ± 28.922.1 ± 11.631.5 ± 17.321.4 ± 7.2
(129)RYGB69.2 ± 29.031.1 ± 11.243.2 ± 15.524.3 ± 5.8
SG57.9 ± 17.817.8 ± 7.142.1 ± 20.717.0 ± 8.8
(193)RYGB322 ± 16.3*−10.6 ± −15.530.6 ± 21.6*−5.8 ± −10.0

ALT, alanine aminotransferase; AST, aspartate aminotransferase; LSG, sleeve gastrectomy; post-OP, postoperative; pre-OP, preoperative; RYGB, Roux-en-Y gastric bypass. *Values are provided as IU/L.

Metabolic syndrome and insulin resistance after metabolic surgery

Metabolic syndrome is defined by a group of factors that increases the risk of coronary heart disease (CHD), atherosclerotic diseases and T2DM. Its main components are visceral obesity, atherogenic dyslipidemia, insulin resistance in the peripheral tissue as well as in the liver and endothelial dysfunction (133). There are several definitions, which have been updated over the years. Metabolic surgery has been shown in multiple studies to produce significant weight loss and enhance or rectify many of the symptoms of metabolic syndrome including T2DM, hypertension, sleep apnea and dyslipidemia (110, 134, 135). There is a recent publication that compared RYGB and SG for metabolic syndrome resolution (136). The authors reported that at a 4-year follow-up, RYGB had a significant resolution of all metabolic syndromes’ factors by 37.6%, while SG also reduced all metabolic syndrome components by 26.8% (except hypertriglyceridemia and hyperglycemia). They concluded that RYGB and SG were associated with similar proportion of resolution of metabolic syndrome. Another study comparing RYGB and SG in metabolic syndrome remission with a 3-year follow-up confirmed these results with 58% for RYGB and 59% for SG respectively (137). Boza et al. performed a study reporting metabolic syndrome´s remission at a minimum of 5 years of follow-up, but only with RYGB (138). They reported a resolution rate of 86% postoperatively. In summary, there appears to be no relevant difference between RYGB and SG regarding resolution of the metabolic syndrome. The underlying cause of the improvement in the metabolic syndrome is the reduction of the insulin resistance in the peripheral tissue such as adipose tissue and muscle but also in the liver (129, 139, 140, 141, 142, 143). However, there are no studies comparing the effects of RYGB and SG on insulin resistance in the various tissues. Of note, some recent studies showed that the metabolic effects of metabolic procedures remain even in patients with weight loss failure (144, 145).

Arterial hypertension after metabolic surgery

Arterial hypertension is linked to obesity and other metabolic disease, and it plays an essential role in the development of kidney disease, especially in patients with T2DM. Metabolic surgery has been demonstrated to be an effective procedure for hypertension resolution (115). Since the early 90s, several studies have shown that RYGB is an effective therapy for arterial hypertension in patients with obesity (146, 147) (Table 4). A study by Sugerman et al. reported that at 5- to 7-year follow-up, there was a 66% hypertension remission rate in patients who underwent RYGB (148). Several studies also reported the effects of RYGB and SG on resolution of arterial hypertension. A current meta-analysis, which includes all studies independent of their quality, found that RYGB achieves a higher rate of arterial hypertension resolution than SG (60% vs 51%, P = 0.001, OR: 1.43 (95% CI: 1.15–1.77)) (116). In contrast, there are no differences between RYGB and SG when only RCTs are considered (149). However, the follow-up in these studies is short and limited with only two studies having a follow-up >12 months. The recent results from the SM-BOSS trial after 5 years support the finding that there is no difference in resolution of arterial hypertension between RYGB and SG with 71.2% vs 65.2% respectively (61). The remaining patients had all an improvement of their arterial hypertension again with no difference between the two procedures. Taken together, there is currently no evidence that one operation is superior for resolution of arterial hypertensions compared to the other until long-term data from RCTs are available.

Table 4

Effect of RYGB and SG on arterial hypertension.

ReferenceSurgery% Pre-OP (%)% Remission (%)Follow-up (years)
(151)RYGB21.4665
SG19.2605
(60)RYGB71*515
SG71*295
(63)RYGB61.570.35
SG63.462.55
(150)RYGB37.5753
SG31.2503
(194)RYGB17.2403
SG14.3253

*71% of all patients were using medication for arterial hypertension.

HTN, arterial hypertension; LSG, laparoscopic sleeve gastrectomy; pre-OP, preoperative; RYGB, Roux-en-Y gastric bypass.

Dyslipidemia after metabolic surgery

Similar to remission of T2DM and arterial hypertension, metabolic surgery can also efficiently resolve dyslipidemia (51). Also, analyzing uncontrolled data, RYGB appears to have a superior effect on dyslipidemia (116). As in the other obesity-related comorbidities, the benefit of RYGB seems to disappear when only RCTs are analyzed (149). However, in contrast to the other components of metabolic syndrome, RYGB may have a superior impact on dyslipidemia in the long term (Table 5). Yang et al. observed a 100% remission of dyslipidemia after RYGB and 75% after SG after 3 years while Zhang et al. found a 92.5% and 84.6% remission after 5 years respectively (150, 151). The three-year results of the SM-BOSS trial also indicate that the RYGB may achieve a better improvement of dyslipidemia than SG (61). A complete remission of the dyslipidemia was observed in 71.7% of patients after RYGB compared to 43.8% after SG. A further 35.4% of patients after SG experienced an improvement of the dyslipidemia compared to 26.1% after RGYB. However, dyslipidemia was not changed or worsened in 20.8% of patients after SG (2.2% after RYGB). In summary, RYGB may have a slightly superior effect on dyslipidemia than SG although more long-term data are necessary to ultimately answer this question.

Table 5

Effect of RYGB and SG on dyslipidemia.

ReferenceSurgery% Pre-OP (%)% Remission (%)Follow-up (years)
(151)RYGB46.492.55
SG5084.65
(63)RYGB5162.35
SG67.342.65
(60)RYGB35*605
SG35475
(150)RYGB56.21003
SG65.6753

*35% of all patients had dyslipidemia.

LSG, laparoscopic sleeve gastrectomy; RYGB, Roux-en-Y gastric bypass.

Cardiovascular disease after metabolic surgery

Cardiovascular risk (CVR) is estimated using numerous multivariable risk equations, such as the Framingham risk score and its modifications for assessing the risk of CHD (152). According to the American Heart Association, hard atherosclerotic cardiovascular disease (ASCVD) should be focused for estimating CVR instead of CHD alone, also considering atherosclerotic stroke (153). Only few studies assess CVR following metabolic surgery. The randomized, nonblinded, single-center trial of Schauer et al. investigated CVR factors, associated medication use and adverse events (fatal myocardial infarction, stroke) as secondary outcomes following RYGB or SG compared to medical treatment alone (118, 154). Triglyceride and high-density lipoprotein cholesterol levels improved significantly following surgery compared to intensive medical treatment at 3 and 5 years of follow-up (118). Also, a significantly reduced use of cardiovascular and glucose-lowering medications was found following metabolic surgery. Neither RYGB nor SG showed a superior improvement achieving these results, although medication use after RYGB was significantly lower compared to SG. There are no randomized trials investigating CVR factors in particular as a primary outcome. Referring to this, a prospective cohort study of 140 patients undergoing either RYGB or SG showed that both procedures are equally effective, reducing estimated CVR based on the Framingham score to half at 1 year after surgery (155). Randomized trials with long-term follow-up are needed to investigate CVR factors and incidence of events following RYGB compared to SG as primary endpoints.

Short- and long-term complications after metabolic surgery

For a widespread application of new therapies such as metabolic surgery, potential side effects need to be acceptable and the benefit of the therapy needs to outweigh potential complications. The clear and long-lasting health benefit of an invasive therapy is also important for patients to choose such a therapy. The efficacy vs safety assessment is particularly challenging in the treatment of metabolic diseases with operations compared to the conservative medical therapy. It is inherent to operations that they are more invasive and may have more severe complications than non-operative therapies. However, it is very important to realize that the current metabolic operations performed at experienced centers are extremely safe and the mortality rate is < 0.5%, whereas the overall major complication rate is around 2–7% (62, 156, 157).

Non-surgical complications and increased risk for self-harm

Besides the ‘traditional’ complications of surgery, metabolic procedures seem to have additional, unique complications, which need to be addressed. Osteoporosis and an increased risk for fractures has recently been reported after metabolic surgery, especially after malabsorptive operations such as the BPDs (158, 159, 160). Further studies assessing the efficacy of postoperative vitamin and micronutrient supplementation to prevent osteoporosis and nutritional deficiencies are needed to further improve the high safety of metabolic surgery.

A very important area of concern, which has recently been identified, is the increased risk for self-harm and even suicide in patients after bariatric surgery. While the initial studies indicating a higher risk for self-harm and suicide in the post-bariatric patients had a high risk of bias since they compared patients after bariatric surgery with the general population but not with similarly obese patients (161, 162, 163, 164), the study by Neovius et al. showed that patients after bariatric surgery have indeed a higher risk for self-harm and suicide compared to matched patients (165). This study analyzing the SOS study and also patients from the Scandinavian Obesity Registry found a three-fold increased risk for suicide after bariatric surgery. Therefore, every health care provider treating patients before and after metabolic surgery must be aware of these complications and a special emphasis on the prevention and therapy of psychological disorders must be taken (166). In order to prevent self-harm and suicide, our institution screens every patient after metabolic surgery for depression or risk for self-harm/suicide, and we recommend that every institution implements such a screening tool.

Nonetheless, it is very important to put these detrimental outcomes of metabolic surgery in perspective. The success rate and health benefits of metabolic surgery are also much stronger and longer lasting than those of medical therapy (28, 29, 30, 31, 167, 168). The reduced overall long-term mortality, which has been repeatedly shown after metabolic surgery includes mortality from suicide (27, 28, 29, 114), clearly outweighs the potential risks of metabolic operations. Several analyses have confirmed the overall benefit of metabolic operations compared to conservative therapy, especially since the current medical therapy including the newest drugs is not able to reproduce the effects of metabolic surgery (14, 134, 169).

Surgical and operation-related complications

Nonetheless, a safety assessment should also be a concern when RYGB and SG are compared. A recent meta-analysis found that SG has fewer major complications in RCTs than RYGB (3.4% vs 7.5%, P = 0.05; OR: 0.49 (95% CI: 0.24–1.9)), whereas reoperations or re-intervention occurred with the same frequency (156). These findings are in line with the most recent results from the SM-BOSS and SLEEVEPASS trials, which also found no difference in reoperations after 5 years including the conversions of SG to RYGB due to severe GERD (61, 63). In contrast, Melissas et al. found that the long-term complications 5 years after surgery are significantly less in SG patients (1.0%) than after RYGB (3.3%) (62). In summary, both RYGB and SG are very safe operations but SG seems to have less overall complications perioperatively but especially in the long term (Table 6).

Table 6

Perioperative and long-term complications after RYGB and SG.

ReferenceSurgeryPerioperative (%)Long term (%)Medical treatment (%)Reoperations (%)
(62)RYGB33.3n/a2.1
SG2.10.9n/a0.5
(151)RYGB6.225n/an/a
SG12.60n/an/a
(194)RYGB733.310
SG26.633.36.6
(150)RYGB3.7n/a3.1n/a
SG7.1n/a6.2n/a
(60)RYGB26.526n/a14.2
SG13.219n/a8.2
(63)RYGB4.517.3n/a22.1
SG0.914.9n/a15.8

Long term, complications >30 days post-surgery; perioperative, complications within <30 days post-surgery; RYGB, Roux-en-Y gastric bypass; SG, sleeve gastrectomy.

Discussion

Metabolic surgery is currently the most powerful and effective therapy for obesity and its associated diseases such as T2DM, dyslipidemia, NAFLD/NASH and arterial hypertension. It seems to have a causal effect since these operations improve insulin resistance as the underlying cause of the metabolic syndrome (142). Metabolic operations not only achieve successful (>50% EWL after RYGB and SG) long-lasting weight loss but they also reduce overall and comorbidity-associated mortality while improving quality of life (27, 28, 29, 114). Such beneficial long-term effects and sustained weight loss cannot be achieved by lifestyle interventions or conservative therapy (1, 12, 17, 26, 28, 167, 170, 171, 172). A recent meta-analysis showed that metabolic operations not only reduce the incidence of diabetes associated complications but can even improve preexisting diabetic complications, especially diabetic nephropathy in a high rate (173). Interestingly, it seems that some of these metabolic effects even prevail in patients with failed bariatric surgery and weight regain (144, 145). Based on this clear evidence, the leading societies for diabetes therapy proposed new guidelines with early adaption of metabolic surgery for the treatment of patients with T2DM (174).

RYGB and SG are the most commonly performed metabolic operations worldwide since they combine high safety with good metabolic outcomes and a high quality of life (175). In this review, we compare the impact of RYGB and SG on long-term weight loss, remission of T2DM and other metabolic disease while also assessing safety to determine which operations should be the primary choice. While the RYGB may have a slight advantage regarding weight loss, although one should keep in mind that the difference in long-term weight loss after 5 years is about one BMI point or 7% EWL, there are no relevant differences in the remission of comorbidities. One exception might be the remission of T2DM in the subgroup of intermediately severe patients in whom RYGB may have some advantages although this cohort needs to be better defined and the outcomes need to be evaluated in prospective studies. In contrast, there is clear evidence that SG has a superior short- and long-term safety profile compared to RYGB. Another aspect that should be considered when operations are assessed is what the options are in patients with failure of the metabolic operation regarding weight loss but also remission of comorbidities. It is important to know that weight loss failure does not necessarily translate into failure of improvement of comorbidities. Two recent studies showed that the metabolic effects of such operations can still remain despite weight loss failure (144, 145). However, when a reoperation is necessary, the options after SG are more diverse than after RYGB. The most widely used options after RYGB is the conversion to a long-limb (distal) RYGB, pouch resizing, banding of the pouch or endoscopic narrowing of the pouch anastomosis (176, 177, 178). However, the conversion of the failed RYGB to BPD-DS have also been successfully reported in two case series (179, 180). The outcomes of these revisions are in the short term acceptable but there are only few long-term results. In the case of sleeve failure, however, there are more options that include the conversion to an RYGB or into a malabsorptive procedure such as the duodenal switch or a single-anastomosis duodenal-ileale switch (181, 182, 183, 184, 185). Similar to the revisions after failed RYGB, the long-term outcome data after failed SG is also strongly limited.

Taking all these considerations into account, both RYGB and SG need to be prospectively evaluated over a long period of time. In such an evaluation, perioperative complications, weight loss and metabolic outcomes, need for revisions independent of the indication but also the complications and outcomes of a revisional surgery need to be considered. After such a thorough analysis, the ideal metabolic operation can be determined. Other avenues of research should also attempt to better characterize patients prior to the first operation, including BMI, comorbidities but also genetic factors, with the aim to develop prognostic scores that allow to select the appropriate procedure.

As of now, both RYGB and SG are the metabolic operations of choice yielding excellent short- and long-term results. The choice of operation should be based on extensive discussion and information about the benefits and drawbacks of each operation together with the patient.

Declaration of interest

The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of this review.

Funding

This research did not receive any specific grant from any funding agency in the public, commercial or not-for-profit sector.

Author contribution statement

A T B and B P M helped with concept and design. A T B, J D G H and K M S contributed to data acquisition (literature search). A T B, J D G H and K M S drafted the manuscript. F N, F B and B P M helped in critical revisions.

References

  • 1

    Kissane NA & Pratt JS. Medical and surgical treatment of obesity. Best Practice and Research: Clinical Anaesthesiology 2011 25 1125. (https://doi.org/10.1016/j.bpa.2011.01.001)

    • Search Google Scholar
    • Export Citation
  • 2

    Wild S, Roglic G, Green A, Sicree R & King H. Global prevalence of diabetes: estimates for the year 2000 and projections for 2030. Diabetes Care 2004 27 10471053. (https://doi.org/10.2337/diacare.27.5.1047)

    • Search Google Scholar
    • Export Citation
  • 3

    Cusi K. Treatment of patients with type 2 diabetes and non-alcoholic fatty liver disease: current approaches and future directions. Diabetologia 2016 59 11121120. (https://doi.org/10.1007/s00125-016-3952-1)

    • Search Google Scholar
    • Export Citation
  • 4

    Forbes JM & Cooper ME. Mechanisms of diabetic complications. Physiological Reviews 2013 93 137188. (https://doi.org/10.1152/physrev.00045.2011)

    • Search Google Scholar
    • Export Citation
  • 5

    Ong JP & Younossi ZM. Epidemiology and natural history of NAFLD and NASH. Clinical Liver Disease 2007 11 116, vii. (https://doi.org/10.1016/j.cld.2007.02.009)

    • Search Google Scholar
    • Export Citation
  • 6

    Hartmann J, Jacobs S, Eberhard S, von Lengerke T & Amelung V. Analysing predictors for future high-cost patients using German SHI data to identify starting points for prevention. European Journal of Public Health 2016 26 549555. (https://doi.org/10.1093/eurpub/ckv248)

    • Search Google Scholar
    • Export Citation
  • 7

    Costanzo P, Cleland JG, Pellicori P, Clark AL, Hepburn D, Kilpatrick ES, Perrone-Filardi P, Zhang J & Atkin SL. The obesity paradox in type 2 diabetes mellitus: relationship of body mass index to prognosis: a cohort study. Annals of Internal Medicine 2015 162 610618. (https://doi.org/10.7326/M14-1551)

    • Search Google Scholar
    • Export Citation
  • 8

    Alva ML, Gray A, Mihaylova B, Leal J & Holman RR. The impact of diabetes-related complications on healthcare costs: new results from the UKPDS (UKPDS 84). Diabetic Medicine 2015 32 459466. (https://doi.org/10.1111/dme.12647)

    • Search Google Scholar
    • Export Citation
  • 9

    American Diabetes A. Economic costs of diabetes in the U.S. in 2012. Diabetes Care 2013 36 10331046. (https://doi.org/10.2337/dc12-2625)

    • Search Google Scholar
    • Export Citation
  • 10

    Nichols GA, Vupputuri S & Lau H. Medical care costs associated with progression of diabetic nephropathy. Diabetes Care 2011 34 23742378. (https://doi.org/10.2337/dc11-0475)

    • Search Google Scholar
    • Export Citation
  • 11

    Schaufler TM & Wolff M. Cost effectiveness of preventive screening programmes for type 2 diabetes mellitus in Germany. Applied Health Economics and Health Policy 2010 8 191202. (https://doi.org/10.2165/11532880-000000000-00000)

    • Search Google Scholar
    • Export Citation
  • 12

    Franz MJ, Boucher JL, Rutten-Ramos S & VanWormer JJ. Lifestyle weight-loss intervention outcomes in overweight and obese adults with type 2 diabetes: a systematic review and meta-analysis of randomized clinical trials. Journal of the Academy of Nutrition and Dietetics 2015 115 14471463. (https://doi.org/10.1016/j.jand.2015.02.031)

    • Search Google Scholar
    • Export Citation
  • 13

    Terranova CO, Brakenridge CL, Lawler SP, Eakin EG & Reeves MM. Effectiveness of lifestyle-based weight loss interventions for adults with type 2 diabetes: a systematic review and meta-analysis. Diabetes, Obesity and Metabolism 2015 17 371378. (https://doi.org/10.1111/dom.12430)

    • Search Google Scholar
    • Export Citation
  • 14

    Picot J, Jones J, Colquitt JL, Gospodarevskaya E, Loveman E, Baxter L & Clegg AJ. The clinical effectiveness and cost-effectiveness of bariatric (weight loss) surgery for obesity: a systematic review and economic evaluation. Health Technology Assessment 2009 13 1190, 215–357, iii–iv.

    • Search Google Scholar
    • Export Citation
  • 15

    Mann T, Tomiyama AJ, Westling E, Lew AM, Samuels B, Chatman J. Medicare’s search for effective obesity treatments: diets are not the answer. American Psychologist 2007 62 220233. (https://doi.org/10.1037/0003-066X.62.3.220)

    • Search Google Scholar
    • Export Citation
  • 16

    Ruospo M, Saglimbene VM, Palmer SC, De Cosmo S, Pacilli A, Lamacchia O, Cignarelli M, Fioretto P, Vecchio M & Craig JC et al. Glucose targets for preventing diabetic kidney disease and its progression. Cochrane Database of Systematic Reviews 2017 6 CD010137.

    • Search Google Scholar
    • Export Citation
  • 17

    Look ARG, Wing RR, Bolin P, Brancati FL, Bray GA, Clark JM, Coday M, Crow RS, Curtis JM & Egan CM et al. Cardiovascular effects of intensive lifestyle intervention in type 2 diabetes. New England Journal of Medicine 2013 369 145154. (https://doi.org/10.1056/NEJMoa1212914)

    • Search Google Scholar
    • Export Citation
  • 18

    Singhal M, Unni S, Schauerhamer M, Nguyen H, Hurd J & McAdam-Marx C. Real-world glycemic control from GLP-1RA therapy with and without concurrent insulin in patients with type 2 diabetes. Journal of Managed Care and Specialty Pharmacy 2017 23 267275. (https://doi.org/10.18553/jmcp.2017.16334)

    • Search Google Scholar
    • Export Citation
  • 19

    Marso SP, Daniels GH, Brown-Frandsen K, Kristensen P, Mann JF, Nauck MA, Nissen SE, Pocock S, Poulter NR & Ravn LS et al. Liraglutide and cardiovascular outcomes in type 2 diabetes. New England Journal of Medicine 2016 375 311322. (https://doi.org/10.1056/NEJMoa1603827)

    • Search Google Scholar
    • Export Citation
  • 20

    Zinman B, Wanner C, Lachin JM, Fitchett D, Bluhmki E, Hantel S, Mattheus M, Devins T, Johansen OE & Woerle HJ et al. Empagliflozin, cardiovascular outcomes, and mortality in type 2 diabetes. New England Journal of Medicine 2015 373 21172128. (https://doi.org/10.1056/NEJMoa1504720)

    • Search Google Scholar
    • Export Citation
  • 21

    Zoller H & Tilg H. Nonalcoholic fatty liver disease and hepatocellular carcinoma. Metabolism 2016 65 11511160. (https://doi.org/10.1016/j.metabol.2016.01.010)

    • Search Google Scholar
    • Export Citation
  • 22

    Musso G, Cassader M & Gambino R. Non-alcoholic steatohepatitis: emerging molecular targets and therapeutic strategies. Nature Reviews Drug Discovery 2016 15 249274. (https://doi.org/10.1038/nrd.2015.3)

    • Search Google Scholar
    • Export Citation
  • 23

    Ratziu V, Goodman Z & Sanyal A. Current efforts and trends in the treatment of NASH. Journal of Hepatology 2015 62 S65S75. (https://doi.org/10.1016/j.jhep.2015.02.041)

    • Search Google Scholar
    • Export Citation
  • 24

    Sharma AM & Kushner RF. A proposed clinical staging system for obesity. International Journal of Obesity 2009 33 289295. (https://doi.org/10.1038/ijo.2009.2)

    • Search Google Scholar
    • Export Citation
  • 25

    Padwal RS, Pajewski NM, Allison DB & Sharma AM. Using the Edmonton obesity staging system to predict mortality in a population-representative cohort of people with overweight and obesity. CMAJ 2011 183 E1059E1066. (https://doi.org/10.1503/cmaj.110387)

    • Search Google Scholar
    • Export Citation
  • 26

    Adams TD, Davidson LE, Litwin SE, Kim J, Kolotkin RL, Nanjee MN, Gutierrez JM, Frogley SJ, Ibele AR & Brinton EA et al. Weight and metabolic outcomes 12 years after gastric bypass. New England Journal of Medicine 2017 377 11431155. (https://doi.org/10.1056/NEJMoa1700459)

    • Search Google Scholar
    • Export Citation
  • 27

    Adams TD, Gress RE, Smith SC, Halverson RC, Simper SC, Rosamond WD, Lamonte MJ, Stroup AM & Hunt SC. Long-term mortality after gastric bypass surgery. New England Journal of Medicine 2007 357 753761. (https://doi.org/10.1056/NEJMoa066603)

    • Search Google Scholar
    • Export Citation
  • 28

    Sjostrom L, Peltonen M, Jacobson P, Sjostrom CD, Karason K, Wedel H, Ahlin S, Anveden A, Bengtsson C & Bergmark G et al. Bariatric surgery and long-term cardiovascular events. JAMA 2012 307 5665. (https://doi.org/10.1001/jama.2011.1914)

    • Search Google Scholar
    • Export Citation
  • 29

    Sjostrom L, Narbro K, Sjostrom CD, Karason K, Larsson B, Wedel H, Lystig T, Sullivan M, Bouchard C & Carlsson B et al. Effects of bariatric surgery on mortality in Swedish obese subjects. New England Journal of Medicine 2007 357 741752. (https://doi.org/10.1056/NEJMoa066254)

    • Search Google Scholar
    • Export Citation
  • 30

    Sjostrom L, Peltonen M, Jacobson P, Ahlin S, Andersson-Assarsson J, Anveden A, Bouchard C, Carlsson B, Karason K & Lonroth H et al. Association of bariatric surgery with long-term remission of type 2 diabetes and with microvascular and macrovascular complications. JAMA 2014 311 22972304. (https://doi.org/10.1001/jama.2014.5988)

    • Search Google Scholar
    • Export Citation
  • 31

    Sjostrom L, Gummesson A, Sjostrom CD, Narbro K, Peltonen M, Wedel H, Bengtsson C, Bouchard C, Carlsson B & Dahlgren S et al. Effects of bariatric surgery on cancer incidence in obese patients in Sweden (Swedish Obese Subjects Study): a prospective, controlled intervention trial. Lancet Oncology 2009 10 653662. (https://doi.org/10.1016/S1470-2045(09)70159-7)

    • Search Google Scholar
    • Export Citation
  • 32

    Schauer PR, Bhatt DL & Kashyap SR. Bariatric surgery or intensive medical therapy for diabetes after 5 years. New England Journal of Medicine 2017 376 1997.

    • Search Google Scholar
    • Export Citation
  • 33

    Mingrone G, Panunzi S, De Gaetano A, Guidone C, Iaconelli A, Nanni G, Castagneto M, Bornstein S & Rubino F. Bariatric-metabolic surgery versus conventional medical treatment in obese patients with type 2 diabetes: 5 year follow-up of an open-label, single-centre, randomised controlled trial. Lancet 2015 386 964973. (https://doi.org/10.1016/S0140-6736(15)00075-6)

    • Search Google Scholar
    • Export Citation
  • 34

    Ikramuddin S, Korner J, Lee WJ, Bantle JP, Thomas AJ, Connett JE, Leslie DB, Inabnet WB 3rd, Wang Q & Jeffery RW et al. Durability of addition of Roux-en-Y gastric bypass to lifestyle intervention and medical management in achieving primary treatment goals for uncontrolled type 2 diabetes in mild to Moderate obesity: a randomized control trial. Diabetes Care 2016 39 15101518. (https://doi.org/10.2337/dc15-2481)

    • Search Google Scholar
    • Export Citation
  • 35

    Cummings DE, Arterburn DE, Westbrook EO, Kuzma JN, Stewart SD, Chan CP, Bock SN, Landers JT, Kratz M & Foster-Schubert KE et al. Gastric bypass surgery vs intensive lifestyle and medical intervention for type 2 diabetes: the CROSSROADS randomised controlled trial. Diabetologia 2016 59 945953. (https://doi.org/10.1007/s00125-016-3903-x)

    • Search Google Scholar
    • Export Citation
  • 36

    Wentworth JM, Playfair J, Laurie C, Ritchie ME, Brown WA, Burton P, Shaw JE & O’Brien PE. Multidisciplinary diabetes care with and without bariatric surgery in overweight people: a randomised controlled trial. Lancet Diabetes and Endocrinology 2014 2 545552. (https://doi.org/10.1016/S2213-8587(14)70066-X)

    • Search Google Scholar
    • Export Citation
  • 37

    Courcoulas AP, Belle SH, Neiberg RH, Pierson SK, Eagleton JK, Kalarchian MA, DeLany JP, Lang W & Jakicic JM. Three-year outcomes of bariatric surgery vs lifestyle intervention for type 2 diabetes mellitus treatment: a randomized clinical trial. JAMA Surgery 2015 150 931940. (https://doi.org/10.1001/jamasurg.2015.1534)

    • Search Google Scholar
    • Export Citation
  • 38

    Yan Y, Sha Y, Yao G, Wang S, Kong F, Liu H, Zhang G, Zhang H, Hu C & Zhang X. Roux-en-Y gastric bypass versus medical treatment for type 2 diabetes mellitus in obese patients: a systematic review and meta-analysis of randomized controlled trials. Medicine 2016 95 e3462. (https://doi.org/10.1097/MD.0000000000003462)

    • Search Google Scholar
    • Export Citation
  • 39

    Muller-Stich BP, Senft JD, Warschkow R, Kenngott HG, Billeter AT, Vit G, Helfert S, Diener MK, Fischer L & Buchler MW et al. Surgical versus medical treatment of type 2 diabetes mellitus in nonseverely obese patients: a systematic review and meta-analysis. Annals of Surgery 2015 261 421429. (https://doi.org/10.1097/SLA.0000000000001014)

    • Search Google Scholar
    • Export Citation
  • 40

    Chen Y, Corsino L, Shantavasinkul PC, Grant J, Portenier D, Ding L & Torquati A. Gastric bypass surgery leads to long-term remission or improvement of type 2 diabetes and significant decrease of microvascular and macrovascular complications. Annals of Surgery 2016 263 11381142. (https:doi.org/10.1097/SLA.0000000000001509)

    • Search Google Scholar
    • Export Citation
  • 41

    Cohen R, Pechy F, Petry T, Correa JL, Caravatto PP & Tzanno-Martins C. Bariatric and metabolic surgery and microvascular complications of type 2 diabetes mellitus. Jornal Brasileiro De Nefrologia 2015 37 399409.

    • Search Google Scholar
    • Export Citation
  • 42

    Banks J, Adams ST, Laughlan K, Allgar V, Miller GV, Jayagopal V, Gale R, Sedman P & Leveson SH. Roux-en-Y gastric bypass could slow progression of retinopathy in type 2 diabetes: a pilot study. Obesity Surgery 2015 25 777781. (https://doi.org/10.1007/s11695-014-1476-7)

    • Search Google Scholar
    • Export Citation
  • 43

    Jackson S, le Roux CW & Docherty NG. Bariatric surgery and microvascular complications of type 2 diabetes mellitus. Current Atherosclerosis Reports 2014 16 453. (https://doi.org/10.1007/s11883-014-0453-x)

    • Search Google Scholar
    • Export Citation
  • 44

    Billeter AT, Probst P, Eichel S, Kopf S, Fischer L, Diener MK, Nawroth PP & Müller-Stich BP. Meta-analysis of metabolic surgery versus medical treatment for microvascular complications in patients with type 2 diabetes mellitus. BJS 2017.

    • Search Google Scholar
    • Export Citation
  • 45

    Billeter AT, Kopf S, Zeier M, Scheurlen K, Fischer L, Schulte TM, Kenngott HG, Israel B, Knefeli P & Buchler MW et al. Renal function in type 2 diabetes following gastric bypass. Deutsches Ärzteblatt International 2016 113 827833. (https://dpi.org/10.3238/arztebl.2016.0827)

    • Search Google Scholar
    • Export Citation
  • 46

    Muller-Stich BP, Billeter AT, Fleming T, Fischer L, Buchler MW & Nawroth PP. Nitrosative stress but not glycemic parameters correlate with improved neuropathy in nonseverely obese diabetic patients after Roux-Y gastric bypass. Surgery for Obesity and Related Diseases 2015 11 847854. (https://doi.org/10.1016/j.soard.2014.12.007)

    • Search Google Scholar
    • Export Citation
  • 47

    Muller-Stich BP, Fischer L, Kenngott HG, Gondan M, Senft J, Clemens G, Nickel F, Fleming T, Nawroth PP & Buchler MW. Gastric bypass leads to improvement of diabetic neuropathy independent of glucose normalization – results of a prospective cohort study (DiaSurg 1 study). Annals of Surgery 2013 258 760765. (https://doi.org/10.1097/SLA.0b013e3182a618b2)

    • Search Google Scholar
    • Export Citation
  • 48

    Gorman DM, le Roux CW & Docherty NG. The effect of bariatric surgery on diabetic retinopathy: good, bad, or both? Diabetes and Metabolism: Journal 2016 40 354364. (https://doi.org/10.4093/dmj.2016.40.5.354)

    • Search Google Scholar
    • Export Citation
  • 49

    Lassailly G, Caiazzo R, Buob D, Pigeyre M, Verkindt H, Labreuche J, Raverdy V, Leteurtre E, Dharancy S & Louvet A et al. Bariatric surgery reduces features of nonalcoholic steatohepatitis in morbidly obese patients. Gastroenterology 2015 149 379388. (https://doi.org/10.1053/j.gastro.2015.04.014)

    • Search Google Scholar
    • Export Citation
  • 50

    Mathurin P, Hollebecque A, Arnalsteen L, Buob D, Leteurtre E, Caiazzo R, Pigeyre M, Verkindt H, Dharancy S & Louvet A et al. Prospective study of the long-term effects of bariatric surgery on liver injury in patients without advanced disease. Gastroenterology 2009 137 532540. (https://doi.org/10.1053/j.gastro.2009.04.052)

    • Search Google Scholar
    • Export Citation
  • 51

    Hanipah ZN & Schauer PR. Surgical treatment of obesity and diabetes. Gastrointestinal Endoscopy Clinics of North America 2017 27 191211. (https://doi.org/10.1016/j.giec.2016.12.005)

    • Search Google Scholar
    • Export Citation
  • 52

    Madsbad S, Dirksen C & Holst JJ. Mechanisms of changes in glucose metabolism and bodyweight after bariatric surgery. Lancet Diabetes and Endocrinology 2014 2 152164. (https://doi.org/10.1016/S2213-8587(13)70218-3)

    • Search Google Scholar
    • Export Citation
  • 53

    Nannipieri M, Baldi S, Mari A, Colligiani D, Guarino D, Camastra S, Barsotti E, Berta R, Moriconi D & Bellini R et al. Roux-en-Y gastric bypass and sleeve gastrectomy: mechanisms of diabetes remission and role of gut hormones. Journal of Clinical Endocrinology and Metabolism 2013 98 43914399. (https://doi.org/10.1210/jc.2013-2538)

    • Search Google Scholar
    • Export Citation
  • 54

    Odstrcil EA, Martinez JG, Santa Ana CA, Xue B, Schneider RE, Steffer KJ, Porter JL, Asplin J, Kuhn JA & Fordtran JS. The contribution of malabsorption to the reduction in net energy absorption after long-limb Roux-en-Y gastric bypass. American Journal of Clinical Nutrition 2010 92 704713. (https://doi.org/10.3945/ajcn.2010.29870)

    • Search Google Scholar
    • Export Citation
  • 55

    Angrisani L, Santonicola A, Iovino P, Vitiello A, Zundel N, Buchwald H, Scopinaro N. Bariatric surgery and endoluminal procedures: IFSO Worldwide Survey 2014. Obesity Surgery 2017 27 22792289. (https://doi.org/10.1007/s11695-017-2666-x)

    • Search Google Scholar
    • Export Citation
  • 56

    Higa KH, Pournaras J, Welbourn R, Dixon J, Kinsman R, Walton P. Third IFSO global registry report. 2017.

  • 57

    Himpens J, Cadiere GB, Bazi M, Vouche M, Cadiere B & Dapri G. Long-term outcomes of laparoscopic adjustable gastric banding. Archives of Surgery 2011 146 802807. (https://doi.org/10.1001/archsurg.2011.45)

    • Search Google Scholar
    • Export Citation
  • 58

    Khoraki J, Moraes MG, Neto APF, Funk LM, Greenberg JA & Campos GM. Long-term outcomes of laparoscopic adjustable gastric banding. American Journal of Surgery 2018 215 97103. (https://doi.org/10.1016/j.amjsurg.2017.06.027)

    • Search Google Scholar
    • Export Citation
  • 59

    Victorzon M & Tolonen P. Mean fourteen-year, 100% follow-up of laparoscopic adjustable gastric banding for morbid obesity. Surgery for Obesity and Related Diseases 2013 9 753757. (https://doi.org/10.1016/j.soard.2013.05.010)

    • Search Google Scholar
    • Export Citation
  • 60

    Salminen P, Helmio M, Ovaska J, Juuti A, Leivonen M, Peromaa-Haavisto P, Hurme S, Soinio M, Nuutila P & Victorzon M. Effect of laparoscopic sleeve gastrectomy vs laparoscopic Roux-en-Y gastric bypass on weight loss at 5 years among patients with morbid obesity: the SLEEVEPASS randomized clinical trial. JAMA 2018 319 241254. (https://doi.org/10.1001/jama.2017.20313)

    • Search Google Scholar
    • Export Citation
  • 61

    Salm R, Wolnerhanssen BK, Vetter D, Nett P, Gass M, Borbely Y, Peters T, Schiesser M, Schultes B & Beglinger C et al. Laparoscopic sleeve gastrectomy versus Roux-Y-Gastric bypass for morbid obesity-3-year outcomes of the prospective randomized Swiss Multicenter Bypass or Sleeve Study (SM-BOSS). Annals of Surgery 2017 265 466473. (https://doi.org/10.1097/SLA.0000000000001929)

    • Search Google Scholar
    • Export Citation
  • 62

    Melissas J, Stavroulakis K, Tzikoulis V, Peristeri A, Papadakis JA, Pazouki A, Khalaj A & Kabir A. Sleeve gastrectomy vs Roux-en-Y gastric bypass. Data from IFSO-European Chapter Center of Excellence Program. Obesity Surgery 2017 27 847855. (https://doi.org/10.1007/s11695-016-2395-6)

    • Search Google Scholar
    • Export Citation
  • 63

    Peterli R, Wolnerhanssen BK, Peters T, Vetter D, Kroll D, Borbely Y, Schultes B, Beglinger C, Drewe J & Schiesser M et al. Effect of laparoscopic sleeve gastrectomy vs laparoscopic Roux-en-Y gastric bypass on weight loss in patients with morbid obesity: the SM-BOSS randomized clinical trial. JAMA 2018 319 255265. (https://doi.org/10.1001/jama.2017.20897)

    • Search Google Scholar
    • Export Citation
  • 64

    O’Brien PE, MacDonald L, Anderson M, Brennan L & Brown WA. Long-term outcomes after bariatric surgery: fifteen-year follow-up of adjustable gastric banding and a systematic review of the bariatric surgical literature. Annals of Surgery 2013 257 8794.

    • Search Google Scholar
    • Export Citation
  • 65

    Pournaras DJ, Osborne A, Hawkins SC, Vincent RP, Mahon D, Ewings P, Ghatei MA, Bloom SR, Welbourn R & le Roux CW. Remission of type 2 diabetes after gastric bypass and banding: mechanisms and 2 year outcomes. Annals of Surgery 2010 252 966971. (https://doi.org/10.1097/SLA.0b013e3181efc49a)

    • Search Google Scholar
    • Export Citation
  • 66

    Steven S, Hollingsworth KG, Al-Mrabeh A, Avery L, Aribisala B, Caslake M & Taylor R. Very low-calorie diet and 6 months of weight stability in type 2 diabetes: pathophysiological changes in responders and nonresponders. Diabetes Care 2016 39 808815. (https://doi.org/10.2337/dc15-1942)

    • Search Google Scholar
    • Export Citation
  • 67

    Jackness C, Karmally W, Febres G, Conwell IM, Ahmed L, Bessler M, McMahon DJ & Korner J. Very low-calorie diet mimics the early beneficial effect of Roux-en-Y gastric bypass on insulin sensitivity and beta-cell Function in type 2 diabetic patients. Diabetes 2013 62 30273032. (https://doi.org/10.2337/db12-1762)

    • Search Google Scholar
    • Export Citation
  • 68

    Knop FK & Taylor R. Mechanism of metabolic advantages after bariatric surgery: it’s all gastrointestinal factors versus it’s all food restriction. Diabetes Care 2013 36 (Supplement 2) S287S291. (https://doi.org/10.2337/dcS13-2032)

    • Search Google Scholar
    • Export Citation
  • 69

    Lutz TA & Bueter M. Physiological mechanisms behind Roux-en-Y gastric bypass surgery. Digestive Surgery 2014 31 1324. (https://doi.org/10.1159/000354319)

    • Search Google Scholar
    • Export Citation
  • 70

    Berggren J, Lindqvist A, Hedenbro J, Groop L & Wierup N. Roux-en-Y gastric bypass versus calorie restriction: support for surgery per se as the direct contributor to altered responses of insulin and incretins to a mixed meal. Surgery for Obesity and Related Diseases 2017 13 234242. (https://doi.org/10.1016/j.soard.2016.09.017)

    • Search Google Scholar
    • Export Citation
  • 71

    Crujeiras AB, Gomez-Arbelaez D, Zulet MA, Carreira MC, Sajoux I, de Luis D, Castro AI, Baltar J, Baamonde I & Sueiro A et al. Plasma FGF21 levels in obese patients undergoing energy-restricted diets or bariatric surgery: a marker of metabolic stress? International Journal of Obesity 2017 41 15701578. (https://doi.org/10.1038/ijo.2017.138)

    • Search Google Scholar
    • Export Citation
  • 72

    Grayson BE, Hakala-Finch AP, Kekulawala M, Laub H, Egan AE, Ressler IB, Woods SC, Herman JP, Seeley RJ & Benoit SC et al. Weight loss by calorie restriction versus bariatric surgery differentially regulates the hypothalamo-pituitary-adrenocortical axis in male rats. Stress 2014 17 484493. (https://doi.org/10.3109/10253890.2014.967677)

    • Search Google Scholar
    • Export Citation
  • 73

    Carlin AM, Zeni TM, English WJ, Hawasli AA, Genaw JA, Krause KR, Schram JL, Kole KL, Finks JF & Birkmeyer JD et al. The comparative effectiveness of sleeve gastrectomy, gastric bypass, and adjustable gastric banding procedures for the treatment of morbid obesity. Annals of Surgery 2013 257 791797. (https://doi.org/10.1097/SLA.0b013e3182879ded)

    • Search Google Scholar
    • Export Citation
  • 74

    Dogan K, Gadiot RP, Aarts EO, Betzel B, van Laarhoven CJ, Biter LU, Mannaerts GH, Aufenacker TJ, Janssen IM & Berends FJ. Effectiveness and safety of sleeve gastrectomy, gastric bypass, and adjustable gastric banding in morbidly obese patients: a multicenter, retrospective, matched cohort study. Obesity Surgery 2015 25 11101118. (https://doi.org/10.1007/s11695-014-1503-8)

    • Search Google Scholar
    • Export Citation
  • 75

    Purnell JQ, Selzer F, Wahed AS, Pender J, Pories W, Pomp A, Dakin G, Mitchell J, Garcia L & Staten MA et al. Type 2 diabetes remission rates after laparoscopic gastric bypass and gastric banding: results of the longitudinal assessment of bariatric surgery study. Diabetes Care 2016 39 11011107. (https://doi.org/10.2337/dc15-2138)

    • Search Google Scholar
    • Export Citation
  • 76

    Batterham RL & Cummings DE. Mechanisms of diabetes improvement following bariatric/metabolic surgery. Diabetes Care 2016 39 893901. (https://doi.org/10.2337/dc16-0145)

    • Search Google Scholar
    • Export Citation
  • 77

    Benaiges D, Mas-Lorenzo A, Goday A, Ramon JM, Chillaron JJ, Pedro-Botet J & Flores-Le Roux JA. Laparoscopic sleeve gastrectomy: more than a restrictive bariatric surgery procedure? World Journal of Gastroenterology 2015 21 1180411814. (https://doi.org/10.3748/wjg.v21.i41.11804)

    • Search Google Scholar
    • Export Citation
  • 78

    Ye J, Hao Z, Mumphrey MB, Townsend RL, Patterson LM, Stylopoulos N, Munzberg H, Morrison CD, Drucker DJ & Berthoud HR. GLP-1 receptor signaling is not required for reduced body weight after RYGB in rodents. American Journal of Physiology: Regulatory, Integrative and Comparative Physiology 2014 306 R352R362. (https://doi.org/10.1152/ajpregu.00491.2013)

    • Search Google Scholar
    • Export Citation
  • 79

    Ryan KK, Tremaroli V, Clemmensen C, Kovatcheva-Datchary P, Myronovych A, Karns R, Wilson-Perez HE, Sandoval DA, Kohli R & Backhed F et al. FXR is a molecular target for the effects of vertical sleeve gastrectomy. Nature 2014 509 (7499) 183188. (https://doi.org/10.1038/nature13135)

    • Search Google Scholar
    • Export Citation
  • 80

    Lutz TA & Bueter M. The physiology underlying Roux-en-Y gastric bypass – a status report. American Journal of Physiology: Regulatory, Integrative and Comparative Physiology 2014 307 (11) R1275R1291. (https://doi.org/10.1152/ajpregu.00185.2014)

    • Search Google Scholar
    • Export Citation
  • 81

    Flynn CR, Albaugh VL, Cai S, Cheung-Flynn J, Williams PE, Brucker RM, Bordenstein SR, Guo Y, Wasserman DH & Abumrad NN. Bile diversion to the distal small intestine has comparable metabolic benefits to bariatric surgery. Nature Communications 2015 6 7715. (https://doi.org/10.1038/ncomms8715)

    • Search Google Scholar
    • Export Citation
  • 82

    Karamanakos SN, Vagenas K, Kalfarentzos F & Alexandrides TK. Weight loss, appetite suppression, and changes in fasting and postprandial ghrelin and peptide-YY levels after Roux-en-Y gastric bypass and sleeve gastrectomy: a prospective, double blind study. Annals of Surgery 2008 247 401407. (https://doi.org/10.1097/SLA.0b013e318156f012)

    • Search Google Scholar
    • Export Citation
  • 83

    Mason EE & Ito C. Gastric bypass. Annals of Surgery 1969 170 329339. (https://doi.org/10.1097/00000658-196909010-00003)

  • 84

    Wittgrove AC, Clark GW & Tremblay LJ. Laparoscopic gastric bypass, Roux-en-Y: preliminary report of five cases. Obesity Surgery 1994 4 353357. (https://doi.org/10.1381/096089294765558331)

    • Search Google Scholar
    • Export Citation
  • 85

    Wittgrove AC & Clark GW. Laparoscopic gastric bypass, Roux-en-Y- 500 patients: technique and results, with 3–60 month follow-up. Obesity Surgery 2000 10 233239. (https://doi.org/10.1381/096089200321643511)

    • Search Google Scholar
    • Export Citation
  • 86

    Valezi AC, Marson AC, Merguizo RA & Costa FL. Roux-en-Y gastric bypass: limb length and weight loss. Arquivos Brasileiros de Cirurgia Digestiva 2014 27 (Supplement 1) 5658. (https://doi.org/10.1590/s0102-6720201400s100014)

    • Search Google Scholar
    • Export Citation
  • 87

    Nergaard BJ, Leifsson BG, Hedenbro J & Gislason H. Gastric bypass with long alimentary limb or long pancreato-biliary limb – long-term results on weight loss, resolution of co-morbidities and metabolic parameters. Obesity Surgery 2014 24 15951602. (https://doi.org/10.1007/s11695-014-1245-7)

    • Search Google Scholar
    • Export Citation
  • 88

    Lee WJ, Yu PJ, Wang W, Chen TC, Wei PL & Huang MT. Laparoscopic Roux-en-Y versus mini-gastric bypass for the treatment of morbid obesity: a prospective randomized controlled clinical trial. Annals of Surgery 2005 242 2028. (https://doi.org/10.1097/01.sla.0000167762.46568.98)

    • Search Google Scholar
    • Export Citation
  • 89

    Lee WJ, Ser KH, Lee YC, Tsou JJ, Chen SC & Chen JC. Laparoscopic Roux-en-Y vs. mini-gastric bypass for the treatment of morbid obesity: a 10-year experience. Obesity Surgery 2012 22 18271834. (https://doi.org/10.1007/s11695-012-0726-9)

    • Search Google Scholar
    • Export Citation
  • 90

    IFSO 2017 22nd world congress. Obesity Surgery 2017 27 11253.

  • 91

    Kaidar-Person O, Person B, Szomstein S & Rosenthal RJ. Nutritional deficiencies in morbidly obese patients: a new form of malnutrition? Part A: vitamins. Obesity Surgery 2008 18 870876. (https://doi.org/10.1007/s11695-007-9349-y)

    • Search Google Scholar
    • Export Citation
  • 92

    Malinowski SS. Nutritional and metabolic complications of bariatric surgery. American Journal of the Medical Sciences 2006 331 219225. (https://doi.org/10.1097/00000441-200604000-00009)

    • Search Google Scholar
    • Export Citation
  • 93

    Thurnheer M, Bisang P, Ernst B & Schultes B. A novel distal very long Roux-en Y gastric bypass (DVLRYGB) as a primary bariatric procedure – complication rates, weight loss, and nutritional/metabolic changes in the first 355 patients. Obesity Surgery 2012 22 14271436. (https://doi.org/10.1007/s11695-012-0708-y)

    • Search Google Scholar
    • Export Citation
  • 94

    Brolin RE, LaMarca LB, Kenler HA & Cody RP. Malabsorptive gastric bypass in patients with superobesity. Journal of Gastrointestinal Surgery 2002 6 195203. (https://doi.org/10.1016/S1091-255X(01)00022-1)

    • Search Google Scholar
    • Export Citation
  • 95

    Poghosyan T, Caille C, Moszkowicz D, Hanachi M, Carette C, Bouillot JL. Roux-en-Y gastric bypass for the treatment of severe complications after omega-loop gastric bypass. Surgery for Obesity and Related Diseases 2017 13 988994. (https://doi.org/10.1016/j.soard.2016.12.003)

    • Search Google Scholar
    • Export Citation
  • 96

    Hess DS, Hess DW & Oakley RS. The biliopancreatic diversion with the duodenal switch: results beyond 10 years. Obesity Surgery 2005 15 408416. (https://doi.org/10.1381/0960892053576695)

    • Search Google Scholar
    • Export Citation
  • 97

    Daskalakis M & Weiner RA. Sleeve gastrectomy as a single-stage bariatric operation: indications and limitations. Obesity Facts 2009 2 (Supplement 1) 810. (https://doi.org/10.1159/000198239)

    • Search Google Scholar
    • Export Citation
  • 98

    Moy J, Pomp A, Dakin G, Parikh M & Gagner M. Laparoscopic sleeve gastrectomy for morbid obesity. American Journal of Surgery 2008 196 e56e59. (https://doi.org/10.1016/j.amjsurg.2008.04.008)

    • Search Google Scholar
    • Export Citation
  • 99

    Cottam D, Qureshi FG, Mattar SG, Sharma S, Holover S, Bonanomi G, Ramanathan R & Schauer P. Laparoscopic sleeve gastrectomy as an initial weight-loss procedure for high-risk patients with morbid obesity. Surgical Endoscopy 2006 20 859863. (https://doi.org/10.1007/s00464-005-0134-5)

    • Search Google Scholar
    • Export Citation
  • 100

    Mognol P, Chosidow D & Marmuse JP. Laparoscopic sleeve gastrectomy as an initial bariatric operation for high-risk patients: initial results in 10 patients. Obesity Surgery 2005 15 10301033. (https://doi.org/10.1381/0960892054621242)

    • Search Google Scholar
    • Export Citation
  • 101

    Regan JP, Inabnet WB, Gagner M & Pomp A. Early experience with two-stage laparoscopic Roux-en-Y gastric bypass as an alternative in the super-super obese patient. Obesity Surgery 2003 13 861864. (https://doi.org/10.1381/096089203322618669)

    • Search Google Scholar
    • Export Citation
  • 102

    Silecchia G, Boru C, Pecchia A, Rizzello M, Casella G, Leonetti F & Basso N. Effectiveness of laparoscopic sleeve gastrectomy (first stage of biliopancreatic diversion with duodenal switch) on co-morbidities in super-obese high-risk patients. Obesity Surgery 2006 16 11381144. (https://doi.org/10.1381/096089206778392275)

    • Search Google Scholar
    • Export Citation
  • 103

    El Chaar M, Hammoud N, Ezeji G, Claros L, Miletics M & Stoltzfus J. Laparoscopic sleeve gastrectomy versus laparoscopic Roux-en-Y gastric bypass: a single center experience with 2 years follow-up. Obesity Surgery 2015 25 254262. (https://doi.org/10.1007/s11695-014-1388-6)

    • Search Google Scholar
    • Export Citation
  • 104

    Soto FC, Gari V, de la Garza JR, Szomstein S & Rosenthal RJ. Sleeve gastrectomy in the elderly: a safe and effective procedure with minimal morbidity and mortality. Obesity Surgery 2013 23 14451449. (https://doi.org/10.1007/s11695-013-0992-1)

    • Search Google Scholar
    • Export Citation
  • 105

    Alexandrou A, Armeni E, Kouskouni E, Tsoka E, Diamantis T & Lambrinoudaki I. Cross-sectional long-term micronutrient deficiencies after sleeve gastrectomy versus Roux-en-Y gastric bypass: a pilot study. Surgery for Obesity and Related Diseases 2014 10 262268. (https://doi.org/10.1016/j.soard.2013.07.014)

    • Search Google Scholar
    • Export Citation
  • 106

    Kwon Y, Kim HJ, Lo Menzo E, Park S, Szomstein S & Rosenthal RJ. Anemia, iron and vitamin B deficiencies after sleeve gastrectomy compared to Roux-en-Y gastric bypass: a meta-analysis. Surgery for Obesity and Related Diseases 2014 10 589597. (https://doi.org/10.1016/j.soard.2013.12.005)

    • Search Google Scholar
    • Export Citation
  • 107

    Gehrer S, Kern B, Peters T, Christoffel-Courtin C & Peterli R. Fewer nutrient deficiencies after laparoscopic sleeve gastrectomy (LSG) than after laparoscopic Roux-Y-gastric bypass (LRYGB)-a prospective study. Obesity Surgery 2010 20 447453. (https://doi.org/10.1007/s11695-009-0068-4)

    • Search Google Scholar
    • Export Citation
  • 108

    Fischer L, Hildebrandt C, Bruckner T, Kenngott H, Linke GR, Gehrig T, Buchler MW & Muller-Stich BP. Excessive weight loss after sleeve gastrectomy: a systematic review. Obesity Surgery 2012 22 721731. (https://doi.org/10.1007/s11695-012-0616-1)

    • Search Google Scholar
    • Export Citation
  • 109

    Noel P, Nedelcu M, Eddbali I, Manos T, Gagner M. What are the long-term results 8 years after sleeve gastrectomy? Surgery for Obesity and Related Diseases 2017 13 11101115. (https://doi.org/10.1016/j.soard.2017.03.007)

    • Search Google Scholar
    • Export Citation
  • 110

    Sarela AI, Dexter SP, O’Kane M, Menon A & McMahon MJ. Long-term follow-up after laparoscopic sleeve gastrectomy: 8–9-year results. Surgery for Obesity and Related Diseases 2012 8 679684. (https://doi.org/10.1016/j.soard.2011.06.020)

    • Search Google Scholar
    • Export Citation
  • 111

    Mehaffey JH, LaPar DJ, Clement KC, Turrentine FE, Miller MS, Hallowell PT & Schirmer BD. 10-year outcomes after Roux-en-Y gastric bypass. Annals of Surgery 2016 264 121126. (https://doi.org/10.1097/SLA.0000000000001544)

    • Search Google Scholar
    • Export Citation
  • 112

    Obeid NR, Malick W, Concors SJ, Fielding GA, Kurian MS & Ren-Fielding CJ. Long-term outcomes after Roux-en-Y gastric bypass: 10- to 13-year data. Surgery for Obesity and Related Diseases 2016 12 1120. (https://doi.org/10.1016/j.soard.2015.04.011)

    • Search Google Scholar
    • Export Citation
  • 113

    Fischer L, Wekerle AL, Bruckner T, Wegener I, Diener MK, Frankenberg MV, Gartner D, Schon MR, Raggi MC & Tanay E et al. BariSurg trial: sleeve gastrectomy versus Roux-en-Y gastric bypass in obese patients with BMI 35–60 kg/m2 – a multi-centre randomized patient and observer blind non-inferiority trial. BMC Surgery 2015 15 87. (https://doi.org/10.1186/s12893-015-0072-7)

    • Search Google Scholar
    • Export Citation
  • 114

    Pontiroli AE, Zakaria AS, Mantegazza E, Morabito A, Saibene A, Mozzi E, Micheletto G & Group LW. Long-term mortality and incidence of cardiovascular diseases and type 2 diabetes in diabetic and nondiabetic obese patients undergoing gastric banding: a controlled study. Cardiovascular Diabetology 2016 15 39. (https://doi.org/10.1186/s12933-016-0347-z)

    • Search Google Scholar
    • Export Citation
  • 115

    Romeo S, Maglio C, Burza MA, Pirazzi C, Sjoholm K, Jacobson P, Svensson PA, Peltonen M, Sjostrom L & Carlsson LM. Cardiovascular events after bariatric surgery in obese subjects with type 2 diabetes. Diabetes Care 2012 35 26132617. (https://doi.org/10.2337/dc12-0193)

    • Search Google Scholar
    • Export Citation
  • 116

    Li J, Lai D & Wu D. Laparoscopic Roux-en-Y gastric bypass versus laparoscopic sleeve gastrectomy to treat morbid obesity-related comorbidities: a systematic review and meta-analysis. Obesity Surgery 2016 26 429442. (https://doi.org/10.1007/s11695-015-1996-9)

    • Search Google Scholar
    • Export Citation
  • 117

    Osland E, Yunus RM, Khan S, Memon B & Memon MA. Diabetes improvement and resolution following laparoscopic vertical sleeve gastrectomy (LVSG) versus laparoscopic Roux-en-Y gastric bypass (LRYGB) procedures: a systematic review of randomized controlled trials. Surgical Endoscopy 2017 31 19521963. (https://doi.org/10.1007/s00464-016-5202-5)

    • Search Google Scholar
    • Export Citation
  • 118

    Schauer PR, Bhatt DL, Kirwan JP, Wolski K, Aminian A, Brethauer SA, Navaneethan SD, Singh RP, Pothier CE & Nissen SE et al. Bariatric surgery versus intensive medical therapy for diabetes – 5-year outcomes. New England Journal of Medicine 2017 376 641651. (https://doi.org/10.1056/NEJMoa1600869)

    • Search Google Scholar
    • Export Citation
  • 119

    Aminian A, Brethauer SA, Andalib A, Nowacki AS, Jimenez A, Corcelles R, Hanipah ZN, Punchai S, Bhatt DL & Kashyap SR et al. Individualized metabolic surgery score: procedure selection based on diabetes severity. Annals of Surgery 2017 266 650657. (https://doi.org/10.1097/SLA.0000000000002407)

    • Search Google Scholar
    • Export Citation
  • 120

    Panunzi S, Carlsson L, De Gaetano A, Peltonen M, Rice T, Sjostrom L, Mingrone G & Dixon JB. Determinants of diabetes remission and glycemic control after bariatric surgery. Diabetes Care 2016 39 166174. (https://doi.org/10.2337/dc15-0575)

    • Search Google Scholar
    • Export Citation
  • 121

    Panunzi S, De Gaetano A, Carnicelli A & Mingrone G. Predictors of remission of diabetes mellitus in severely obese individuals undergoing bariatric surgery: do BMI or procedure choice matter? A meta-analysis. Annals of Surgery 2015 261 459467. (https://doi.org/10.1097/SLA.0000000000000863)

    • Search Google Scholar
    • Export Citation
  • 122

    Doycheva I, Patel N, Peterson M & Loomba R. Prognostic implication of liver histology in patients with nonalcoholic fatty liver disease in diabetes. Journal of Diabetes and its Complications 2013 27 293300. (https://doi.org/10.1016/j.jdiacomp.2012.10.008)

    • Search Google Scholar
    • Export Citation
  • 123

    Tuyama AC & Chang CY. Non-alcoholic fatty liver disease. Journal of Diabetes 2012 4 266280. (https://doi.org/10.1111/j.1753-0407.2012.00204.x)

    • Search Google Scholar
    • Export Citation
  • 124

    Perumpail RB, Wong RJ, Ahmed A & Harrison SA. Hepatocellular carcinoma in the setting of non-cirrhotic nonalcoholic fatty liver disease and the metabolic syndrome: US experience. Digestive Diseases and Sciences 2015 60 31423148. (https://doi.org/10.1007/s10620-015-3821-7)

    • Search Google Scholar
    • Export Citation
  • 125

    Anstee QM, Targher G & Day CP. Progression of NAFLD to diabetes mellitus, cardiovascular disease or cirrhosis. Nature Reviews Gastroenterology and Hepatology 2013 10 330344. (https://doi.org/10.1038/nrgastro.2013.41)

    • Search Google Scholar
    • Export Citation
  • 126

    Charlton MR, Burns JM, Pedersen RA, Watt KD, Heimbach JK & Dierkhising RA. Frequency and outcomes of liver transplantation for nonalcoholic steatohepatitis in the United States. Gastroenterology 2011 141 12491253. (https://doi.org/10.1053/j.gastro.2011.06.061)

    • Search Google Scholar
    • Export Citation
  • 127

    Lomonaco R, Bril F, Portillo-Sanchez P, Ortiz-Lopez C, Orsak B, Biernacki D, Lo M, Suman A, Weber MH & Cusi K. Metabolic impact of nonalcoholic steatohepatitis in obese patients with type 2 diabetes. Diabetes Care 2016 39 632638. (https://doi.org/10.2337/dc15-1876)

    • Search Google Scholar
    • Export Citation
  • 128

    Yang B, Yang HP, Ward KK, Sahasrabuddhe VV & McGlynn KA. Bariatric surgery and liver cancer in a consortium of academic medical centers. Obesity Surgery 2016 26 696700. (https://doi.org/10.1007/s11695-016-2051-1)

    • Search Google Scholar
    • Export Citation
  • 129

    Billeter AT, Senft J, Gotthardt D, Knefeli P, Nickel F, Schulte T, Fischer L, Nawroth PP, Buchler MW & Muller-Stich BP. Combined non-alcoholic fatty liver disease and type 2 diabetes mellitus: sleeve gastrectomy or gastric bypass? – a controlled matched pair study of 34 patients. Obesity Surgery 2016 26 18671874. (https://doi.org/10.1007/s11695-015-2006-y)

    • Search Google Scholar
    • Export Citation
  • 130

    Kalinowski P, Paluszkiewicz R, Ziarkiewicz-Wroblewska B, Wroblewski T, Remiszewski P, Grodzicki M & Krawczyk M. Liver function in patients with nonalcoholic fatty liver disease randomized to Roux-en-Y gastric bypass versus sleeve gastrectomy: a secondary analysis of a randomized clinical trial. Annals of Surgery 2017 266 738745. (https://doi.org/10.1097/SLA.0000000000002397)

    • Search Google Scholar
    • Export Citation
  • 131

    Nickel F, Tapking C, Benner L, Sollors J, Billeter AT, Kenngott HG, Bokhary L, Schmid M, von Frankenberg M & Fischer L et al. Bariatric surgery as an efficient treatment for non-alcoholic fatty liver disease in a prospective study with 1-year follow-up: BariScan study. Obesity Surgery 2017 Epub. (https://doi.org/10.1007/s11695-017-3012-z)

    • Search Google Scholar
    • Export Citation
  • 132

    Caiazzo R, Lassailly G, Leteurtre E, Baud G, Verkindt H, Raverdy V, Buob D, Pigeyre M, Mathurin P & Pattou F. Roux-en-Y gastric bypass versus adjustable gastric banding to reduce nonalcoholic fatty liver disease: a 5-year controlled longitudinal study. Annals of Surgery 2014 260 893898. (https://doi.org/10.1097/SLA.0000000000000945)

    • Search Google Scholar
    • Export Citation
  • 133

    Huang PL. A comprehensive definition for metabolic syndrome. Disease Models and Mechanisms 2009 2 231237. (https://doi.org/10.1242/dmm.001180)

    • Search Google Scholar
    • Export Citation
  • 134

    Aminian A, Daigle CR, Romero-Talamas H, Kashyap SR, Kirwan JP, Brethauer SA, Schauer PR. Risk prediction of complications of metabolic syndrome before and 6 years after gastric bypass. Surgery for Obesity and Related Diseases 2014 10 576582. (https://doi.org/10.1016/j.soard.2014.01.025)

    • Search Google Scholar
    • Export Citation
  • 135

    Inabnet WB 3rd, Winegar DA, Sherif B & Sarr MG. Early outcomes of bariatric surgery in patients with metabolic syndrome: an analysis of the bariatric outcomes longitudinal database. Journal of the American College of Surgeons 2012 214 550556. (https://doi.org/10.1016/j.jamcollsurg.2011.12.019)

    • Search Google Scholar
    • Export Citation
  • 136

    Eid GM, Brethauer S, Mattar SG, Titchner RL, Gourash W & Schauer PR. Laparoscopic sleeve gastrectomy for super obese patients: forty-eight percent excess weight loss after 6 to 8 years with 93% follow-up. Annals of Surgery 2012 256 262265. (https://doi.org/10.1097/SLA.0b013e31825fe905)

    • Search Google Scholar
    • Export Citation
  • 137

    Casella G, Soricelli E, Giannotti D, Collalti M, Maselli R, Genco A, Redler A & Basso N. Long-term results after laparoscopic sleeve gastrectomy in a large monocentric series. Surgery for Obesity and Related Diseases 2016 12 757762. (https://doi.org/10.1016/j.soard.2015.09.028)

    • Search Google Scholar
    • Export Citation
  • 138

    Boza C, Daroch D, Barros D, Leon F, Funke R & Crovari F. Long-term outcomes of laparoscopic sleeve gastrectomy as a primary bariatric procedure. Surgery for Obesity and Related Diseases 2014 10 11291133. (https://doi.org/10.1016/j.soard.2014.03.024)

    • Search Google Scholar
    • Export Citation
  • 139

    Dadson P, Landini L, Helmio M, Hannukainen JC, Immonen H, Honka MJ, Bucci M, Savisto N, Soinio M & Salminen P et al. Effect of bariatric surgery on adipose tissue glucose metabolism in different depots in patients with or without type 2 diabetes. Diabetes Care 2016 39 292299.

    • Search Google Scholar
    • Export Citation
  • 140

    Xu XJ, Apovian C, Hess D, Carmine B, Saha A, Ruderman N. Improved insulin sensitivity 3 months after RYGB surgery is associated with increased subcutaneous adipose tissue AMPK activity and decreased oxidative stress. Diabetes 2015 64 31553159. (https://doi.org/10.2337/db14-1765)

    • Search Google Scholar
    • Export Citation
  • 141

    Andersson DP, Eriksson Hogling D, Thorell A, Toft E, Qvisth V, Naslund E, Thorne A, Wiren M, Lofgren P & Hoffstedt J et al. Changes in subcutaneous fat cell volume and insulin sensitivity after weight loss. Diabetes Care 2014 37 18311836. (https://doi.org/10.2337/dc13-2395)

    • Search Google Scholar
    • Export Citation
  • 142

    Roslin MS, Dudiy Y, Weiskopf J, Damani T & Shah P. Comparison between RYGB, DS, and VSG effect on glucose homeostasis. Obesity Surgery 2012 22 12811286. (https://doi.org/10.1007/s11695-012-0686-0)

    • Search Google Scholar
    • Export Citation
  • 143

    Bradley D, Conte C, Mittendorfer B, Eagon JC, Varela JE, Fabbrini E, Gastaldelli A, Chambers KT, Su X & Okunade A et al. Gastric bypass and banding equally improve insulin sensitivity and beta cell function. Journal of Clinical Investigation 2012 122 46674674. (https://doi.org/10.1172/JCI64895)

    • Search Google Scholar
    • Export Citation
  • 144

    Haskins IN, Corcelles R, Froylich D, Boules M, Hag A, Burguera B, Schauer PR, Kroh M & Brethauer SA. Primary inadequate weight loss after Roux-en-Y gastric bypass is not associated with poor cardiovascular or metabolic outcomes: experience from a single institution. Obesity Surgery 2017 27 676680. (https://doi.org/10.1007/s11695-016-2328-4)

    • Search Google Scholar
    • Export Citation
  • 145

    Aminian A, Jamal M, Augustin T, Corcelles R, Kirwan JP, Schauer PR & Brethauer SA. Failed surgical weight loss does not necessarily mean failed metabolic effects. Diabetes Technology and Therapeutics 2015 17 682684. (https://doi.org/10.1089/dia.2015.0064)

    • Search Google Scholar
    • Export Citation
  • 146

    Edholm D, Svensson F, Naslund I, Karlsson FA, Rask E & Sundbom M. Long-term results 11 years after primary gastric bypass in 384 patients. Surgery for Obesity and Related Diseases 2013 9 708713. (https://doi.org/10.1016/j.soard.2012.02.011)

    • Search Google Scholar
    • Export Citation
  • 147

    Karlsson J, Taft C, Ryden A, Sjostrom L & Sullivan M. Ten-year trends in health-related quality of life after surgical and conventional treatment for severe obesity: the SOS intervention study. International Journal of Obesity 2007 31 12481261. (https://doi.org/10.1038/sj.ijo.0803573)

    • Search Google Scholar
    • Export Citation
  • 148

    Sugerman HJ, Wolfe LG, Sica DA & Clore JN. Diabetes and hypertension in severe obesity and effects of gastric bypass-induced weight loss. Annals of Surgery 2003 237 751756.

    • Search Google Scholar
    • Export Citation
  • 149

    Osland E, Yunus RM, Khan S, Memon B & Memon MA. Changes in non-diabetic comorbid disease status following laparoscopic vertical sleeve gastrectomy (LVSG) versus laparoscopic Roux-En-Y Gastric Bypass (LRYGB) procedures: a systematic review of randomized controlled trials. Obesity Surgery 2017 27 12081221. (https://doi.org/10.1007/s11695-016-2469-5)

    • Search Google Scholar
    • Export Citation
  • 150

    Yang J, Wang C, Cao G, Yang W, Yu S, Zhai H & Pan Y. Long-term effects of laparoscopic sleeve gastrectomy versus roux-en-Y gastric bypass for the treatment of Chinese type 2 diabetes mellitus patients with body mass index 28–35 kg/m2. BMC Surgery 2015 15 88. (https://doi.org/10.1186/s12893-015-0074-5)

    • Search Google Scholar
    • Export Citation
  • 151

    Zhang Y, Zhao H, Cao Z, Sun X, Zhang C, Cai W, Liu R, Hu S & Qin M. A randomized clinical trial of laparoscopic Roux-en-Y gastric bypass and sleeve gastrectomy for the treatment of morbid obesity in China: a 5-year outcome. Obesity Surgery 2014 24 16171624.

    • Search Google Scholar
    • Export Citation
  • 152

    Wilson PW, D’Agostino RB, Levy D, Belanger AM, Silbershatz H & Kannel WB. Prediction of coronary heart disease using risk factor categories. Circulation 1998 97 18371847. (https://doi.org/10.1161/01.CIR.97.18.1837)

    • Search Google Scholar
    • Export Citation
  • 153

    Lackland DT, Elkind MS, D’Agostino R Sr, Dhamoon MS, Goff DC Jr, Higashida RT, McClure LA, Mitchell PH, Sacco RL & Sila CA et al. Inclusion of stroke in cardiovascular risk prediction instruments: a statement for healthcare professionals from the American Heart Association/American Stroke Association. Stroke 2012 43 19982027. (https://doi.org/10.1161/STR.0b013e31825bcdac)

    • Search Google Scholar
    • Export Citation
  • 154

    Schauer PR, Bhatt DL, Kirwan JP, Wolski K, Brethauer SA, Navaneethan SD, Aminian A, Pothier CE, Kim ES & Nissen SE et al. Bariatric surgery versus intensive medical therapy for diabetes – 3-year outcomes. New England Journal of Medicine 2014 370 (21) 20022013. (https://doi.org/10.1056/NEJMoa1401329)

    • Search Google Scholar
    • Export Citation
  • 155

    Benaiges D, Goday A, Ramon JM, Hernandez E, Pera M, Cano JF & Obemar G. Laparoscopic sleeve gastrectomy and laparoscopic gastric bypass are equally effective for reduction of cardiovascular risk in severely obese patients at one year of follow-up. Surgery for Obesity and Related Diseases 2011 7 575580. (https://doi.org/10.1016/j.soard.2011.03.002)

    • Search Google Scholar
    • Export Citation
  • 156

    Osland E, Yunus RM, Khan S, Alodat T, Memon B & Memon MA. Postoperative early major and minor complications in Laparoscopic Vertical Sleeve Gastrectomy (LVSG) versus Laparoscopic Roux-en-Y Gastric Bypass (LRYGB) procedures: a meta-analysis and systematic review. Obesity Surgery 2016 26 22732284. (https://doi.org/10.1007/s11695-016-2101-8)

    • Search Google Scholar
    • Export Citation
  • 157

    Birkmeyer NJ, Dimick JB, Share D, Hawasli A, English WJ, Genaw J, Finks JF, Carlin AM, Birkmeyer JD & Michigan Bariatric Surgery C. Hospital complication rates with bariatric surgery in Michigan. JAMA 2010 304 435442. (https://doi.org/10.1001/jama.2010.1034)

    • Search Google Scholar
    • Export Citation
  • 158

    Rousseau C, Jean S, Gamache P, Lebel S, Mac-Way F, Biertho L, Michou L & Gagnon C. Change in fracture risk and fracture pattern after bariatric surgery: nested case-control study. BMJ 2016 354 i3794. (https://doi.org/10.1136/bmj.i3794)

    • Search Google Scholar
    • Export Citation
  • 159

    Nakamura KM, Haglind EG, Clowes JA, Achenbach SJ, Atkinson EJ, Melton LJ 3rd & Kennel KA. Fracture risk following bariatric surgery: a population-based study. Osteoporosis International 2014 25 151158. (https;//doi.org/10.1007/s00198-013-2463-x)

    • Search Google Scholar
    • Export Citation
  • 160

    Lalmohamed A, de Vries F, Bazelier MT, Cooper A, van Staa TP, Cooper C & Harvey NC. Risk of fracture after bariatric surgery in the United Kingdom: population based, retrospective cohort study. BMJ 2012 345 e5085. (https://doi.org/10.1136/bmj.e5085)

    • Search Google Scholar
    • Export Citation
  • 161

    Tindle HA, Omalu B, Courcoulas A, Marcus M, Hammers J & Kuller LH. Risk of suicide after long-term follow-up from bariatric surgery. American Journal of Medicine 2010 123 10361042. (https://doi.org/10.1016/j.amjmed.2010.06.016)

    • Search Google Scholar
    • Export Citation
  • 162

    Morgan DJ & Ho KM. Incidence and risk factors for deliberate self-harm, mental illness, and suicide following bariatric surgery: a state-wide population-based linked-data cohort study. Annals of Surgery 2017 265 244252. (https://doi.org/10.1097/SLA.0000000000001891)

    • Search Google Scholar
    • Export Citation
  • 163

    Peterhansel C, Petroff D, Klinitzke G, Kersting A & Wagner B. Risk of completed suicide after bariatric surgery: a systematic review. Obesity Reviews 2013 14 369382. (https://doi.org/10.1111/obr.12014)

    • Search Google Scholar
    • Export Citation
  • 164

    Herpertz S, Kielmann R, Wolf AM, Langkafel M, Senf W & Hebebrand J. Does obesity surgery improve psychosocial functioning? A systematic review. International Journal of Obesity and Related Metabolic Disorders 2003 27 13001314. (https://doi.org/10.1038/sj.ijo.0802410)

    • Search Google Scholar
    • Export Citation
  • 165

    Neovius M, Bruze G, Jacobson P, Sjoholm K, Johansson K, Granath F, Sundstrom J, Naslund I, Marcus C & Ottosson J et al. Risk of suicide and non-fatal self-harm after bariatric surgery: results from two matched cohort studies. Lancet Diabetes and Endocrinology 2018 6 197207. (https://doi.org/10.1016/S2213-8587(17)30437-0)

    • Search Google Scholar
    • Export Citation
  • 166

    Mitchell JE, Crosby R, de Zwaan M, Engel S, Roerig J, Steffen K, Gordon KH, Karr T, Lavender J & Wonderlich S. Possible risk factors for increased suicide following bariatric surgery. Obesity 2013 21 665672. (https://doi.org/10.1002/oby.20066)

    • Search Google Scholar
    • Export Citation
  • 167

    Neovius M, Narbro K, Keating C, Peltonen M, Sjoholm K, Agren G, Sjostrom L & Carlsson L. Health care use during 20 years following bariatric surgery. JAMA 2012 308 11321141. (https://doi.org/10.1001/2012.jama.11792)

    • Search Google Scholar
    • Export Citation
  • 168

    Reges O, Greenland P, Dicker D, Leibowitz M, Hoshen M, Gofer I, Rasmussen-Torvik LJ & Balicer RD. Association of bariatric surgery using laparoscopic banding, Roux-en-Y gastric bypass, or laparoscopic sleeve gastrectomy vs usual care obesity management with all-cause mortality. JAMA 2018 319 279290. (https://doi.org/10.1001/jama.2017.20513)

    • Search Google Scholar
    • Export Citation
  • 169

    Miras AD & le Roux CW. Can medical therapy mimic the clinical efficacy or physiological effects of bariatric surgery? International Journal of Obesity 2014 38 325333. (https;//doi.org/10.1038/ijo.2013.205)

    • Search Google Scholar
    • Export Citation
  • 170

    MacLean PS, Wing RR, Davidson T, Epstein L, Goodpaster B, Hall KD, Levin BE, Perri MG, Rolls BJ & Rosenbaum M et al. NIH working group report: innovative research to improve maintenance of weight loss. Obesity 2015 23 715. (https://doi.org/10.1002/oby.20967)

    • Search Google Scholar<