Menoufia Medical Journal

: 2019  |  Volume : 32  |  Issue : 4  |  Page : 1239--1245

Assessment of metabolic bariatric surgery for the remisson of obesity and type 2 diabetes

Adel M Khalf1, Abd Al-Kareem Elias1, Farag Khalil2,  
1 Department of General Surgery, Faculty of Medicine, Al-Azhar University – Assuit Branch, Assuit, Egypt
2 Department of Internal Medicine, Faculty of Medicine, Al-Azhar University, Cairo, Egypt

Correspondence Address:
Abd Al-Kareem Elias
Lecturer of General Surgery, Department of General Surgery, Faculty of Medicine, Al-Azhar University, Assuit


Objectives The aim of this study was to assess the short-term remission of both obesity and type 2 diabetes (T2D) after metabolic bariatric surgery (MBS). Background The prevalence of obesity is increasing at a rapid rate internationally, paralleled with an increase in the number of people with T2D. Bariatric surgery may induce a lot of anatomical, physiologic, and hormonal changes that improve diabetes with obesity, with durable effects. Patients and methods This study includes 20 obese diabetic patients who underwent MBS treatment of obesity and T2D. Surgical outcome, weight loss, glycated hemoglobin level, comorbidities, and complications were recorded. Patients were followed up every week for 1 month, and then on every month of the first year. All patients were followed up for at least 1 year. Results In the studies, the mean age was 40.08 ± 2 years, male/female ratio was 8/12, and mean BMI was 35.3. The mean operative time and estimated blood loss of sleeve gastrectomy are significantly less than Roux-en-Y gastric bypass. After surgery, mean BMI and mean glycated hemoglobin was reduced, with significant weight reduction (P < 0.001). Conclusion MBS is an effective procedure for treating morbid obesity and T2D which results in sustained weight loss and a high resolution of comorbidities.

How to cite this article:
Khalf AM, Elias AA, Khalil F. Assessment of metabolic bariatric surgery for the remisson of obesity and type 2 diabetes.Menoufia Med J 2019;32:1239-1245

How to cite this URL:
Khalf AM, Elias AA, Khalil F. Assessment of metabolic bariatric surgery for the remisson of obesity and type 2 diabetes. Menoufia Med J [serial online] 2019 [cited 2020 Apr 9 ];32:1239-1245
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Obesity is a major health problem that affects basal physical function. Bariatric surgery was thought to enhance weight loss by causing gastric restriction and/or malabsorption. Altered metabolic state after bariatric surgery was encountered. Consequently, the term 'metabolic' surgery is being more and more adopted with respect to the helpful effects of these procedures in chronic diseases like diabetes [1]. However, discrete parts of the gastrointestinal tract differentially influence glucose homeostasis and may be influenced by various types of bariatric/metabolic procedures. Rubino and Marescaux [2] study initiated many basic studies, in parallel with the anatomy of the gastrointestinal tract as a key regulator of energy and glucose homeostasis and improved the understanding of the mechanism of the remission of type 2 diabetes (T2D) after metabolic surgery. Diabetes remission results from improvement in both insulin resistance and beta-cell dysfunction, mainly the increase in early-phase insulin release [3]. Nevertheless, the dramatic resolution of T2D was induced by the interaction of multiple organ-related pathways involving the brain, gut, liver, pancreas, muscle, adipose tissue, and others [4].

The pathophysiology of T2D may be owing to a malfunction of the duodenum glycemic regulation mechanism. Three important anatomic changes after MBS surgery may initiate the success of the remission of T2D, as following gastric restriction which decreasing calories intakes and followed by weight loss, as in sleeve gastrectomy (SG), was provides an average of 15% total weight loss in the long term associated with a decrease of ghrelin, which may be important in the prevention of weight regain [5]. Duodenum exclusion effect and upper intestine nutrient absorption (sensing) may decrease fat absorption, change bile acid enterohepatic flow and glycemic control through a complex series of hormonal and neural response, and initiate feedback mechanisms through a gut–brain–liver neuron axis to regulate glycemia (and helping in the resolution of T2D) [6]. There is rapid delivery of food to the distal bowel (or short common channel) with gut hormone response with excluding the duodenum and the pyloric functions after rerouting gastrointestinal tract of gastric bypass. Therefore, it may rapidly deliver incompletely digested food to the distal bowl, which may induce a strong gut hormone change, mainly glucagon-like peptide 1 and peptide YY [7]. This effect may induce fluctuation of bile acid composition and alter intestinal microbiota. Bile acid is a molecule that may play an important role in T2D remission after metabolic surgery [8].

The aim of the present study was to evaluate the pathophysiology and metabolic response of both obesity and T2D, with describe the anatomic changes undergoing metabolic bariatric surgery (MBS) [Roux-en-Y gastric bypass (RYGB) and SG], and assessment of short-term results of bariatric metabolic surgery in the remission of obesity and T2D.

 Patient and Methods

This prospective study included 20 obese patients with T2D (3 years at least), having BMI between 35 and 45 kg/m 2, with their ages ranged from 35 to 55 years, after trial of all acceptable medical measures, however, having not achieved clinically useful weight loss, between April 2016 and September 2018 at Department of General Surgery, Faculty of Medicine, Al-Azhar University Hospital. The Medical Ethics Committee at Alzhar University approved this study. Informed consent was taken from all patients who were generally fit for anesthesia and surgery. Exclusion criteria included patients older than 55 years or younger than 35 years, diabetes type 1 or diabetes type 2 on insulin, body mass index (BMI) less than 30 or more than 45, malignant disease, endocrinal disease, and psychic disease. All patients were subjected to full history taking, clinical examination, laboratory, radiological evaluation, and directed specialty consultation (endocrine, anesthesia, nutrition, and psychiatric consultation). The diagnosis of diabetes is based on official recommendation by the abbreviated report of WHO consultation, published in 2011, as follows: the patient is considered to be T2D when level of glycated hemoglobin (HbA1C) is more than or equal to 6.5 in two dosages, high-risk patients for diabetes when HbA1C level is between 5.7 and 6.4%, and normal patients when level of HbA1C is less than 5.7%.

The types of bariatric operation [Figure 1] and [Figure 2] are usually codecided by the patient themselves and the surgeon, which included either (a) SG (causes weight loss by diminish the amount of food the stomach can hold), or (b) bypass surgery (causes malabsorptive by diminish absorption of nutrients). Morbidly obese patients were assigned in two groups (SG and RYGB), with 10 patients each. The primary end point is assessment of surgical outcome, operation time, hospital stay, and postoperative complications (minor, major, and mortality). The secondary end point is assessment of weight loss, remission of T2D, and laboratory evaluation of nutritional status during every visit.{Figure 1}{Figure 2}

Preoperative and operative deep venous thrombosis (DVT) prophylaxis (as miniheparinization and reverse Trendelenburg position) was initiated. General anesthesia was given. The surgeon stands between two legs of patient with an assistant on both sides. Pneumoperitoneum is established up to 15 mmHg. Four to six ports are inserted routinely.

Sleeve gastrectomy

SG consists of removing 80% of the stomach creating a tube-like stomach remnant with the rest of the intestinal intact by resecting the greater curvature from the distal antrum (4 cm proximal to the pylorus) to the angle of His including the complete fundus, using a 36-Fr-size bougie as a calibration tube. The resected part of the stomach was removed from the extended umbilical trocar site. A running absorbable seromuscular invagination suture was applied to the staple line with calibration tube at the side to prevent hemorrhage and leakage, but it is a nonreversible procedure and has the potential for long-term vitamin deficiencies [Figure 1]b.

This procedure works by several mechanisms. First, it significantly restricts the amount of food intake by a new smaller pouch and helps to decrease the amount of food (and thus calories) that can be consumed. The greater effect, however, looks to be the effect the surgery has on gut hormones that suppress hunger, reduce appetite, and improve satiety associated with a relatively short hospital stay.

Roux-en-Y gastric bypass

Gastric bypass has traditionally been considered the gold standard bariatric procedure [Figure 2]b. In RYGB, a small 15- to 30-ml pouch is created from the proximal stomach; this pouch is connected to a loop of jejunum, creating a gastrojejunostomy. The remainder of the stomach and proximal small bowel is left intact and reanastomosed 80–120 cm distal to the gastrojejunostomy, thus remaining isolated from the digestive flow. The length of biliary limb and Roux limb are not standardized and impossible to measure accurately.

This procedure works by several mechanisms through restricting the amount of food that can be consumed, produces significant long-term weight loss (60–80% excess weight loss), with favorable changes in gut hormones that decrease appetite and augment satiation, and typical maintenance of more than 50% excess weight loss. However, it is technically a more complex operation than the SG and potentially could result in greater complication rates with a longer hospital stay than the SG and long-term vitamin/mineral deficiencies, particularly deficits in vitamin B12, iron, calcium, and folate, which requires adherence to dietary recommendations, life-long vitamin/mineral supplementation, and follow-up compliance.

Statistical analysis

All statistical analyses were performed using statistical package for the social sciences, versus 19.0.0 (SPSS Inc., Chicago, Illinois, USA). Data on patient characteristics, management, and outcome are expressed as a number of patients and percentages, with a significance level of P value less than 0.05.


A total of 20 obese patients underwent MBS. The mean age was 40.08 ± 2 years in SG and 42.03 ± 2 years in RYGB. There was a female dominance, with 12 of the patients being female and the remaining eight being male patients (male/female ratio 8/12) in both group [Figure 3]. The mean BMI was 35.1 in SG and 35.3 in RYGB [Figure 4]. All patients continued their oral hypoglycemic medications before the operation. The mean operative time for SG was 114.6 ± 38.8 min with a mean blood loss of 39.5 ± 38.7 ml, whereas in the RYGB, the mean operative time was 167.48 ± 23.79 min, with average blood loss of 65.79 ± 11.91 ml. The operative time of SG is shorter than RYGB. The estimated blood loss of SG is significantly lesser than RYGB. The average length of hospital stay of SG was 5.0 ± 4.1 days, which were significantly longer than the RYGB, which was 2.89 ± 1.06 days. The early postoperative complication included minor complications (DVT in two patients, with one in each group, and gastroesophageal reflux disease (GERD) in three patients in SG group) and major complications (or overall surgical mortality) owing to pulmonary embolism (sudden death) in one patient in gastric bypass group; no recorded postoperative bleeding or leakage was reported. Regarding postsurgical complications, no statistically significant differences were observed between both the procedures in this study.{Figure 3}{Figure 4}

At 1 week after SG, mean BMI was reduced from 35.1 to 34.3 kg/m 2; at 3 months, mean BMI was reduced to 33.1 kg/m 2; at 6 month, mean BMI was reduced to 32.6; at 9 month, mean BMI was reduced to 31.8; at the end of first year, mean BMI was reduced to 30.6, with a significant weight reduction (P < 0.003). However, after gastric bypass, mean BMI was reduced from 35.3 to 33.9 kg/m 2; at 3 months, mean BMI was reduced to 30.8 kg/m 2; at 6 months, mean BMI was reduced to 29.9; at 9 months, mean BMI was reduced to 29.3; and at the end of first year, mean BMI was reduced to 28.7, with significant weight reduction (P < 0.001). [Figure 4] shows a diagram illustrating a comparison between BMI values at 1, 3, 6, 9, and 12 months, postoperatively [Table 1]. Across all procedures and all metabolic disorders, the improvement of obesity-related comorbidities reached the most optimal effect at 1 years. Across all years, the RYGB group had the highest remission rates of diabetes mellitus, and SG had similar high efficacy in diabetes remission rate to bypass procedures. Our data showed that SG had sustained and durable significant weight loss as RYGB (at least 1 year). At 1 week after SG, a mean HbA1C was reduced from 7.5 to 7.3 kg/m 2; at 3 months after surgery, mean HbA1C was reduced to 6.1; at 6 months, mean HbA1C was reduced to 5.8; at 9 months, mean HbA1C was reduced to 5.5; and the end of first year, it become 5.8, with significant reduction in HbA1C (P < 0.004). In comparison to gastric bypass, mean HbA1C was reduced at 1 week from 7.9 to 7.6; at 3 months, mean HbA1C was 6.03; at 6 months, mean HbA1C was 5.9; at 9 months, mean HbA1C was 6.2; and the end of first year, it became 5.5.9, with a significant HbA1C (P < 0.001). Diabetes resolved after SG in five patient and two patients sustained criteria for diabetes and the rest of the group continued as high risk for diabetes, whereas after RYGB, the diabetes resolved in seven patients, and two patients sustained criteria for diabetes and the last one was consider as high risk for diabetes [Figure 5].{Table 1}{Figure 5}


Primary end point

SG and RYGB are presently the most popular performed MBS for weight reduction and remission of diabetes. In our study, 20 obese diabetic patients (diabesity) underwent MBS and were divided in two equal group. Mean age was 40.08 ± 2 years in SG and 42.03 ± 2 years in RYGB, with no significant difference. There was a female dominance (male/female ratio 8/12) in both groups. These data can be correlated with a steady increase in the prevalence of obesity.

The study done by Vidal et al. [9] showed that there is a significant statistical differences between RYGB and SG in operative time (153 vs. 93 min; P < 0.001), which is comparable to the result of the present study.

The study by Lager and colleagues found there is no statistical significant difference regarding minor or major complications in both RYGB and SG. One patient in the gastric bypass group died 5 days after surgery because of pulmonary embolism which is comparable to the present study [10].

RYGB is called the gold standard technique, but SG seems to be a reliable alternative procedure, with shorter operative time, easier to perform, and less morbidity and mortality.

Secondary end point

For years, it was supposed that RYGB is superior to SG in weight reduction. In a study done by Vidal et al. [9]. A total of 249 consecutive patients operated for morbid obesity were included. One hundred and thirty-five (54.2%) patients underwent RYGB and 114 (45.8%) SG. The percentage of weight loss was similar when comparing both surgical techniques. There were no differences between RYGB and SG at 1 year (95.4 vs. 90.8%), which is comparable to the present study [9].

Interestingly, the percent change in BMI was similar between the patients, and they achieved diabetes remission. Both bariatric procedures were safe and effective, resulting in significant weight loss and favorable effects on comorbidities.

The study done by Girundi and TCBC-MG on 468 patients undergoing RYGB showed that the remission of T2DM was seen in 410 (87.6%) of 468 patients 18 months after the surgery, which being a meaningful difference, with P value less than 0.001. Forty-eight (10.3%) patients sustained criteria for the disease and 10 (2.1%) continued at high risk for T2DM, which is comparable to the present study [11].

In a review prepared by Gill et al., they stated that 66.2% of patients who underwent SG were completely cured of T2D which was reflected by an overall improvement in fasting glucose levels and HbA1C levels allowing the termination of all diabetic medications [12].

Both bariatric procedures were reliable and effective, resulting in significant weight loss and favorable effects on diabetes. As shown in [Table 1], the prevalence of diabetes remission was gradually increased following surgery, regardless of the type of MBS. Ghrelin regulation is disturbed following the SG procedure. SG was also reported to have a hindgut effect with increasing levels of glucagon-like peptide 1 and peptide YY owing to the increased transit time after SG.

The remission of diabetes after BMS had been proposed by five mechanisms which are caloric intake restriction, ghrelin hypothesis with reduction of appetite, duodenum exclusion effect which plays an important role by incretin effect, enhancement of B cell function after food ingestion, hindgut hypothesis, and change of bile acid metabolism and intestinal microbiota, which play important role in energy metabolism [Table 2] [1],[2],[4]. None of these mechanisms have the upper hand over the other, but all of these mechanisms act with each other to induce remission of diabetes which is not only based on weight (WT) reduction but also enterohormonal changes after rearrangement of enteroinsular axis [7].{Table 2}

Although the gold standard for diabetes remission remains the RYGB because similar mechanisms of diabetes remission may be involved and the procedure is easier to perform, the SG could become a valuable alternative. Although our results appear to be encouraging and support SG as an effective treatment strategy for diabetes remission, further studies are needed to allow for definitive conclusions regarding the ideal procedure for obtaining diabetes remission.

Literature review

Lessing et al. [13] concluded that 5 years follow-up after SG of 51 diabetic patients for whom HBA1C offers a retainable weight loss, results were accompanied by long-standing resolution and improvement of diabetes.

Schauer and colleagues included a 5-year follow-up analysis that showed improvement of diabetes after bariatric surgery among patients with a BMI of 27–34, and the results were durable and were superior to that with intensive medical therapy. Laparoscopic SG is a safe procedure for T2D in 941 patients regarding postoperative complication [14].

De Angelis and colleagues concluded that out of 870 laproscopic sleeve gastrectomy (LSG), a postoperative complication in 31 (3.5%) cases was registered: bleeding was the most frequent complication (1.9%). Hemoperitoneum was managed laparoscopically in 9/17 and conservatively in 8/17. However, four patients develop an infected hematoma, two of them treated by drainage and the other two were complicated by late gastric leak treated laparoscopically [15].

MBS is the most successful therapeutic option that causes sustained weight loss and improvement in obesity comorbidities. RYGB and SG are two of the most frequently performed bariatric surgeries. Despite their different anatomical rearrangement, they have remarkably similar success in both weight loss and T2D mellitus remission. Interestingly, they also cause a wide range of endocrine changes. Many of these endocrine changes are reflected specifically within the intestine and are implicated as mechanisms for the metabolic success of the surgery. Kim and Sandoval study shows the long-term (>10 years) outcome of SG procedure and states that it is a simple, effective, and durable procedure, with a better result than the LRYGB procedure [16].

We report findings from a long-term follow up study involving 118 participants following RYGB surgery. The mean duration of follow-up was 10.2 years, with the mean body weight loss of 29.6% (38.5 kg) at the last follow-up. The prevalence of obesity is increasing at a rapid rate internationally, paralleled with an increase in the number of people with T2D. Although the cornerstone of management of both conditions is a lifestyle change, dietary interventions tend to result in only minimal weight loss, which is frequently regained over the subsequent years [17].

Medical therapies for weight loss are only moderately more effective, whereas those used in the management of diabetes control hyperglycemia rather than addressing the underlying pathophysiology. Bariatric surgery has therefore emerged as an apparently effective technique for both conditions, particularly when occurring in association. Whilst high-quality short-term follow up studies now support bariatric surgery as the most effective treatment option available, there is a lack of long-term outcome studies to support its durability and safety [18].

Bariatric surgery can be considered as a second-line therapy in nonobese diabetic patients. In nondiabetic morbidly obese patients, bariatric surgery may prevent the development of T2D mellitus and other comorbidities. Dysregulation of insulin secretion with the hyperinsulinemic state is a serious complication, being the most important predicting factor for this group of surgical patients [19].

The variety of surgical procedures offered for the treatment of morbid obesity and the disagreement between practitioners over the selection of the surgical technique suggests in part that there may be opportunities for improvement of the presently available surgical options [20]. Because of the relative simplicity, good weight result, and less long-term nutritional problems, LSG becomes the most commonly performed bariatric/metabolic surgery worldwide within a decade. However, the known long-term drawback of LSG is the development of GERD, up to 17% (31/58) in our long-term series [21].

In the present study done by Alkhalifah and colleagues, SG shows that this procedure is a safe and durable primary bariatric procedure, with an overall 29.1% weight loss at 10 years and satisfactory resolution of obesity-related comorbidities. Bariatric surgery is the most successful therapeutic option that causes sustained weight loss and improvements in obesity comorbidities. RYGB and SG are two of the most frequently performed bariatric surgeries [22].

Of the various treatment options, bariatric surgery remains the most effective method to achieve a long-term weight loss. Postsurgical weight loss improves all obesity-related comorbidities with a good quality of life and decreased overall mortality rate [23]. Moreover, postbariatric surgical patients have demonstrated 83% reduction in diabetes incidence, 30–40% reduction in myocardial infarction, 42% reduction of cancer in women, and 30–40% reduction in overall mortality [24].


Metabolic surgery is now recommended as a standard treatment option for morbid obesity with T2D. In nondiabetic morbidly obese patients, bariatric surgery may prevent the development of T2D and other comorbidities. In diabetic obese patients, diabetes remission, improvement of blood glucose control, and reduction of antidiabetic medications after bariatric surgery can be sustained for many years with a decrease in overall morbidity and mortality. The short-term studies of patients undergoing bariatric metabolic surgery (RYGB and SG) show that SG is as effective as RYGB in the remission of obesity and T2D. Further study are recommended to evaluate short-term and long-term effects of metabolic surgery.

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Conflicts of interest

There are no conflicts of interest.


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