|Year : 2022 | Volume
| Issue : 1 | Page : 16-23
Medium-Term outcomes after Roux-en-Y-Gastric Bypass: Experience from a Tertiary Healthcare Center from India
Prasanna Ramana Arumugaswamy, Vitish Singla, Sandeep Aggarwal
Department of Surgical Disciplines, All India Institute Of Medical Sciences, AIIMS, New Delhi, India
|Date of Submission||30-Jan-2022|
|Date of Acceptance||23-Mar-2022|
|Date of Web Publication||08-Apr-2022|
Prof. Sandeep Aggarwal
AIIMS, New Delhi
Source of Support: None, Conflict of Interest: None
Background: Roux en Y gastric bypass (RYGB) has been highly effective in weight loss and it has been the procedure of choice for patients suffering from diabetes. There is a high attrition rate in long-term follow-up. Hence, limited long-term data are available. Methodology: We collected retrospectively data from a prospectively maintained institutional database. To increase the long-term follow-up rate, a telephonic interview was conducted with patients who had not come for long-term follow-up. Standard definitions were used for weight loss, weight regain, comorbidities, comorbidity resolution, and nutritional parameters. Results: Of 142 patients who underwent laparoscopic RYGB between 2008 and 2018, 125 patients (M: 33, F: 92; Age: 42.4 ± 5.2 years) were included in the study. The mean % weight loss at 1, 3, 5, and 7 years was 28.9, 31.8, 31.3, and 31.7, respectively. Mean % excess body mass index loss (% EBMIL) at 1, 3, 5, and 7 years was 67.6 ± 18, 73.7 ± 17.9, 71.7 ± 20.7, and 69.5 ± 24.6, respectively. Median weight regain at 3, 5, and 7 years was 8.4%, 12.7%, and 24% of weight lost. Significant weight regain was seen in 1 patient at 3 years and 3 patients at 5 and 7 years of follow-up. Among patients suffering from diabetes, 50.9% had remission and 45.3% had improvement at 1 year. At 5 years, this was 56% and 40%, respectively. Among patients suffering from hypertension, at 5 years, remission was seen in 11 (64.7%) out of 17. Significant improvements were seen in hypothyroidism, OSA, gastroesophageal reflux disease, and lipid profile. There was a statistically significant decrease in mean levels of fasting blood sugar, glycated hemoglobin (HbA1c), hemoglobin, serum calcium, insulin, c-peptide, serum albumin, and total protein and there was an increase in mean Vitamin D levels at 1 year follow-up. There was a decrease in mean levels of folate, total iron-binding capacity, parathyroid hormone, and alkaline phosphatase and an increase in mean Vitamin B12, iron, and ferritin postsurgery. However, this was statistically not significant. Nutritional deficiencies were noted. Seven complications were noted out of 142 procedures and no surgery-related mortality. Three patients had significant weight regain beyond 5 years. Conclusion: RYGB is a safe and effective bariatric procedure with well-sustained results in long run. Nutritional supplementation is required to correct deficiencies.
Keywords: Long term, nutritional deficiency, outcomes, Roux en Y gastric bypass, weight loss, weight regain
|How to cite this article:|
Arumugaswamy PR, Singla V, Aggarwal S. Medium-Term outcomes after Roux-en-Y-Gastric Bypass: Experience from a Tertiary Healthcare Center from India. J Bariatr Surg 2022;1:16-23
|How to cite this URL:|
Arumugaswamy PR, Singla V, Aggarwal S. Medium-Term outcomes after Roux-en-Y-Gastric Bypass: Experience from a Tertiary Healthcare Center from India. J Bariatr Surg [serial online] 2022 [cited 2022 May 21];1:16-23. Available from: http://www.jbsonline.org/text.asp?2022/1/1/16/342766
| Introduction|| |
In search of an effective weight-loss operation without the detrimental side effects of the Jejunoilleal bypass, Edward E. Mason, of the University of Iowa developed the gastric bypass. Roux en Y gastric bypass (RYGB) is regarded as the gold standard of bariatric surgery by some, with superior short- and long-term weight loss and comorbidity resolution. Others have reported comparable outcomes between sleeve gastrectomy and RYGB in terms of weight loss and comorbidity resolution. Preference is given to RYGB especially when there are multiple comorbidities.,
Few studies have been found in the literature that report long-term outcomes. Most of these long-term studies include a large number of open RYGB cases along with laparoscopic RYGB. Mehaffey et al. reported 10-year outcomes of 651 patients who underwent RYGB. More than half of these patients underwent open RYGB. Incisional hernia rates were higher in these patients. This may not be completely relevant when it comes to the safety profile of the procedure as it is well-known fact that overall laparoscopy has made this surgery safer. There are very few studies in the Indian population regarding this aspect, especially mid and long-term studies are lacking.
Very few studies exist from India. Ismail et al. reported 5-year outcomes in 157 Indian patients who underwent RYGB. This study reported only diabetes remission with regards to comorbidities. Mishra et al. reported outcomes in 528 patients undergoing RYGB. Nutritional deficiencies were not reported in both these studies.
Outcomes reported in western literature may not be completely relevant for the Indian cohort, especially in terms of comorbidities and nutritional aspects. Literature is scarce on the mid and long-term outcomes in the Indian population. This study aims to report the short-term and mid-term outcomes of the patients undergoing laparoscopic RYGB in an Indian population.
| Methodology|| |
Data were collected by retrospectively reviewing the prospectively maintained database from medical records of all the patients who underwent laparoscopic RYGB between 2008 and 2019. Also to increase the long-term follow-up rate, telephonic interview was conducted in certain patients who had not come to the hospital for a long-term follow-up.
The patient population included all those undergoing laparoscopic RYGB in our institution from January 2008 to April 2019. All patients satisfied the criteria set by National Institute of Health with body mass index (BMI) >40 kg/m2 or patients with BMI >35 kg/m2 with obesity-associated comorbidities. The patients having severe gastroesophageal reflux disease (GERD), long-standing type 2 diabetes mellitus (T2DM), and BMI >50 kg/m2 were preferred for LRYGB. Each patient was counseled regarding all available options for weight loss and about each bariatric procedure with the surgeon's opinion also being explained clearly. The procedure was decided after giving due consideration to the patient's preference also. All patients were operated on according to standard surgical protocol, by a single-experienced surgeon with experience of more than 10 years.
Preoperatively, all patients were put on very low-calorie diet of approximately 800 kcal and 60 g protein. Preoperative workup included routine blood tests, upper gastrointestinal endoscopy, electrocardiogram, abdominal ultrasound, lower limb Doppler, sleep study, pulmonary function tests, and hormonal and nutritional evaluation according to hospital protocol. The patient was followed up at 3, 6, 12 months, and annually thereafter.
Preoperatively, cefuroxime was used for antibiotic prophylaxis. Under general anesthesia and in reverse Trendelenburg position laparoscopic Roux-en-Y gastric bypass was done with an alimentary limb length of 150 cm and biliopancreatic limb of 70 cm as measured from duodenojejunal flexure. A 30–50cc vertical gastric pouch was created followed by an end to side gastrojejunostomy and side-to-side jejunojejunostomy was done using a three-row endo stapler. The mesenteric defect was closed in all cases. An intraoperative leak test using methylene blue was done to check for the staple line integrity.
Weight was recorded before the surgery and after surgery on each follow-up visit. Total weight loss and % excess weight loss (%EWL) were calculated for each follow-up. Failure was considered if %EWL was less than 50 % after 18 months of surgery. Weight regain was calculated and significant weight regain was considered if regain of more than 25% of lost weight from the nadir weight.,
Diabetes mellitus (DM) was defined as glycated hemoglobin (HbA1c) >6.5 or fasting blood sugar (FBS) >126 mg/dL. Remission was defined as normal measures of glucose metabolism (HbA1c <6 or FBG <100 mg/dL) in the absence of anti-diabetic medications for 1 year, and improvement was defined by a decrease in anti-diabetic medications or better control. Recurrence was considered if there was a deranged diabetic profile in follow-up after there was remission.
Hypertension was defined as blood pressure >140/90 mm Hg. Remission was defined if the patient had normal blood pressure (<120/80) without any antihypertensive medications, and improvement was considered if the patient required a decrease in dosage of antihypertensive medications or a decrease in blood pressure with the same medication.
Obstructive sleep apnea
Obstructive sleep apnea (OSA) was defined as apnea-hypopnea index more than 5 in preoperative polysomnography. Improvement was considered if the patient had a decrease in symptoms of OSA or did not require continuous airway positive pressure postoperatively.
Hypothyroidism was considered in patients taking thyroxine or with abnormal thyroid function tests (TFT) before surgery. Remission was considered if the patient did not require thyroxine with normal TFT. An improvement was considered if the patient had a decrease in the dose of thyroxine.
Gastroesophageal reflux disease
GERD severity symptom (GERD-SS) questionnaire was used to assess the presence of GERD with GERD-SS score >4 or regular use of proton pump inhibitors (PPIs) being defined as GERD. Remission was considered if the patient had no symptoms of GERD without the use of PPI. An improvement was considered if the patient required a decrease in the dose of PPI or a decrease in symptoms. New-onset GERD was defined if the patient developed symptoms of reflux postoperatively or was required to start PPIs.
Anemia was defined as a Hemoglobin level <12 g/dL. Vitamin B12 deficiency as levels <180 pg/ml and folate deficiency as levels <3 ng/ml. Iron deficiency was defined if serum iron was <60 μg/dl. Vitamin D deficiency was defined if levels were <12 ng/ml.
For defining remissions, ASMBS standard definitions were used.
All statistical analysis was done using SPSS 25 (IBM SPSS Statistics for Windows, Version 25.0. Armonk, NY: IBM Corp).
| Results|| |
One hundred and forty-two patients underwent Roux En Y Gastric Bypass from January 2008 to December 2018. A total of 125 patients (M: 33, F: 92; Age: 42.4 ± 5.2 years) were included in the study after the exclusion of patients who were lost to follow-up or did not have records for data analysis. Of the 125 patients, 107 patients had a minimum of 1 year of follow-up.
The percentage of females was higher (73.6%). The cohort was comparable in terms of BMI (45.5 ± 3.55 kg/m2) and age (42.4 ± 5.2 years) among both genders. However, the mean weight was significantly higher among males (M = 128.77, F = 109.15; P < 0.05). [Table 1] shows baseline parameters.
Of the 125 patients, 53 (42.4%; M = 17, F = 36; P = 0.217) were suffering from diabetes, 49 (39.2%; M = 18, F = 31; P < 0.05) patients were suffering from hypertension, 61 (48.8%; M = 21, F = 40; P = 0.047) patients had OSA, 34 (27.2%; M = 5, F = 29; P = 0.070) had hypothyroidism and 35 (28%; M = 6, F = 29; P = 0.143) had GERD. The proportion of males having hypertension and OSA was significantly higher as shown in [Table 2]. Hypothyroidism and GERD were similarly distributed among both genders.
BMI, weight loss, and weight regain
The mean % weight loss at 1, 3, 5, and 7 years was 28.9, 31.8, 31.3, and 31.7, respectively. The mean % excess BMI loss (%EBMIL) at 1, 3, 5, and 7 years was 67.6 ± 18, 73.7 ± 17.9, 71.7 ± 20.7, and 69.5 ± 24.6 respectively with P values as shown in [Table 3] and [Figure 1]. The lowest mean BMI (30.5) was achieved at 3 years. Super obese patients had significantly lower %EBMIL up to 2 years, beyond which there was no significant difference, as shown in [Table 4].
The median weight regain at 3 years, 5 years, and 7 years was 8.4% (range: 1.7%–29.2%), 12.7% (range: 2.4%–58.3%), and 24% (range: 4.4%–56.9%) of weight loss as shown in [Figure 2]. Significant weight regain (%Weight Regain >25) was seen in 1 patient at 3 years and 3 patients at 5 and 7 years' follow-up.
Impact on comorbidities
[Table 5] shows the impact of RYGB on comorbidities. Fifty-three (43.2%) patients had diabetes preoperatively. At 1 year follow-up of the 53 patients, 27 (50.9%) had remission and 24 (45.3%) had improvement in diabetes while 1 (1.9%) patient had no improvement. Of 34 patients, who followed up till 3 years, 19 (55.9%) were in remission, 14 (41.2%) had improvement in diabetes, and 1 (2.9%) patient had no improvement. At 5 years, with 25 patients in follow-up remission was seen in 14 (56%) and improvement in 10 (40%). Four patients had a recurrence of diabetes after remission at 6 years' follow-up. Forty-nine (39.2) patients had hypertension preoperatively. At 1-year follow-up remission was seen in 25 (51.1%) patients, improvement was seen in 15 (30.6%) patients, and no change in 9 (18.4%) patients. Thirty-eight patients followed up till 3 years of which 21 (55.3%) had remission, 9 (23.7%) showed improvement, and no change was seen in 8 (21.1%) patients. Eleven (64.7%) out of 17 patients had remission at 5 years. Recurrence was seen in one patient at 7 years of follow-up. Significant improvements were seen in hypothyroidism, OSA, and GERD as compiled in [Table 5]. Mean TSH (2.99–2.79; P = 0.01) and FT4 (17.47–13.26; p=<0.001) levels were found to decrease significantly. Mean thyroxine dose decreased from 100 μg per day to 85 μg per day at 1 year follow-up (P < 0.001). Improvement rates for hypothyroidism at 1, 3, 5, and 7 years in this study were 65.7%, 55.5%, 64.7%, and 88.9%, and remission was seen in 14.3%, 22.2%, and 17.6% at 1, 3, and 5 years of follow-up.
Impact on lipid profile and other blood parameters
At 1 year, mean low-density lipoprotein decreased from 105.39–92.25 (P = 0.002), mean total cholesterol decreased from 171.43–158.72 (P = 0.002), mean triglyceride levels decreased from 147.33–122.96 (P = 0.168), and mean HDL levels increased from 43.11–47.15 (P = 0.006). Beyond 2 years also the triglyceride and total cholesterol levels showed a falling trend. However, the mean total cholesterol level slightly increased. HDL levels showed an increasing trend. However, the follow-up numbers were very few.
There was a statistically significant decrease in mean levels of FBS, HbA1c, hemoglobin, serum calcium, insulin, c-peptide, serum albumin, and total protein and there was an increase in mean Vitamin D levels at 1 year follow-up as shown in [Table 6]. There was a decrease in mean levels of folate, total iron-binding capacity, parathyroid hormone, and alkaline phosphatase (ALP), and an increase in mean Vitamin B12, iron, and ferritin. However, this was statistically not significant.
[Table 7] shows a compilation of nutritional deficiencies occurring through the follow-up period.
[Table 8] shows the compilation of complications.
| Discussion|| |
In the present study, there was a higher prevalence of type 2 diabetes compared to the reported literature. Significant weight regain was seen in 9.7% of patients at 5 years. Increased prevalence of anemia was noted despite adequate B12 and folate supplementation, indicating insufficient iron supplementation. The most common complication was obstruction.
Of 142 patients operated 125 were included in the study. The exclusions were mainly due to loss to follow-up and the nonavailability of records. Poor follow-up is common in bariatric literature; the reasons may be the increased safety profile of the procedures, patient wellbeing itself, and forgetting the follow-up dates in the long run., Mehaffey et al. in their 10-year outcome study on patients undergoing RYGB reported follow-up rates of 56.3% (363/645) and 23.4% (149/641) at 1 and 3 years. Less than one in five patients had a 5-year follow-up of good quality according to a study by Thereaux et al., regardless of the type of bariatric surgery performed.,
The proportion of females was significantly higher in our cohort. More men had OSA and hypertension. Stroh et al. analyzed a large cohort of 10,000 patients undergoing RYGB. They also reported a higher proportion of women. The mean age of the women was significantly lower in their study. However, clinically, BMI was comparable in both genders. Similar to the present cohort the percentages of hypertension, diabetes, and sleep apnea in men were higher compared to women.
Body mass index, weight loss, and weight regain
In their study of 1087 patients who underwent RYGB Mehaffey et al. reported %EBMIL of 69.7%, 70.1%, 68.8%, and 64.4% at 1, 3, 5, and 7 years, respectively. This is comparable with our results [Table 3]. %EBMIL was highest at 3rd year after which it slightly reduced over 10 years. Similarly, the lowest mean BMI was achieved at 3 years, and thereafter, there was a slight increase in BMI toward 10 years. Most reports similarly describe peak weight loss at 2 or 3 years. It was noted in the present study that the mean %EWL was slightly higher at 7-year follow-up compared to the value at 1 year (58.6% vs. 56.7%). A possible explanation could be the lesser number of patients following up at 7 years compared to 1 year (107 vs. 12). However, when these 12 patients were analyzed separately, the %EWL at 1 year was 70.45% and 69.51% at 7 years. These patients performed well initially, and due to regular follow-up, they sustained their outcomes in the long run.
To define significant weight regain, we used the definition, regain of more than 25% of lost weight from the nadir weight., Baig et al. reported a significant weight regain of 14.6% (n = 159/1092) at 5 years. Sleeve gastrectomy had a significantly higher proportion of weight regain 35.1 (n = 682/1943) at 5 years. The superiority of RYGB in the durability of weight loss may be in part due to a combination of both restrictive and malabsorptive procedures and also the significant alteration in the neurohormonal mechanisms.
Impact on comorbidities
In the meta-analysis by Buchwald et al., they pointed out the prevalence of DM2 in 15.3% and hypertension in 35.4%. The higher prevalence of diabetes in our cohort may be due to the ethnic and genetic characteristics of this cohort. India being the diabetic capital of the world and the cohort being purely an Indian population there is inherently a higher prevalence of diabetes. Gigante et al. found the prevalence of hypertension in 54.4% of their population.
Reported remission rates for diabetes after RYGB ranged from 58% to 78%. Some of the authors combine both remission and improvement for reporting. This can lead to very high percentages. Furthermore, the definitions used to define remission and improvements are not standardized across the literature. Debédat et al. reported a 5-year recurrence rate of 25% in patients who had already achieved diabetes remission following RYGB. In our study at 6 years' follow-up, the recurrence rate was comparable at 28.6%. Factors that contribute toward recurrence could be preoperative insulin use, anti-diabetic medication use, age, and duration of diabetes before surgery.
Obeid et al. reported a remission rate of 46% for hypertension and Higa et al. reported a combined resolution and improvement rate of 86%. Results of the present study were comparable.
Liu et al. reported a decrease in the FT4 and TSH levels, post-RYGB, similar to the present study. Rudnicki reported a remission rate of 10%, decreased thyroxine dosage in 42%, and improvement in thyroid profile in 79% of patients undergoing bariatric surgery with 1–2 years of follow-up. The reason for the improved thyroid profile could be due to decreased subcutaneous and visceral adipocytes which influence the TSH levels through thyroid hormone receptors and TSH receptors. A decrease in ghrelin levels post RYGB also may have a role.,,
Improvements were seen in patients with GERD and OSA as shown in [Table 5]. Frezza et al. reported a reduction of heartburn from 87% to 22% at 1 year. In a study by Perry et al., 100% of patients reported resolution or improvement of symptoms., Fredheim reported a remission rate of 66% in OSA after LRYGB.
Literature indicates raised ALP associated with obese individuals. ALP levels were higher in obese individuals compared to lean individuals. A likely explanation is the presence of ALP isoenzyme in adipose cells., Weight loss resulted in a decrease of ALP in the present study however it was not statistically significant.
In this study, we found that the percentage of patients with anemia increased significantly over 5 years of follow-up as shown in [Table 8]. However, the proportion of patients with Vitamin B12 and folate deficiency reduced gradually over the same period. Reasons for this could be the strict adherence to vitamin supplements in the follow-up program. ASMBS guidelines advise Vitamin B12 supplements of 350–500μg daily after bariatric surgery. We prescribe 2 tablets of Bariatric Fusion per day as lifelong supplementation postsurgery, amounting to approximately 300 μg of Vitamin B12 and 400 μg daily. In follow-up, if any deficiency is noted therapeutic doses are given. There was a significant increase in the percentage of patients having iron deficiency. This can indicate that the supplements for iron are inadequate and could be the reason for an increased prevalence of anemia despite supplements. Anemia with deficiencies of Vitamin B12, iron, and folate have been commonly reported across literature after RYGB.,,, Due to its malabsorptive element, these deficiencies are bound to happen post-RYGB if not supplemented adequately. In this case, it seems the supplementation is adequate in terms of Vitamin B12 and folate but not in the case of iron.
Most bowel obstructions happening after RYGB are attributed to internal herniation. Here, internal hernia rates are significantly less compared to reports from other literature. This may be attributed to the practice of compulsory closure of the mesenteric defect in all procedures. Obeid et al. reported internal herniation rates of 12.8%. Higa et al. reported internal hernia rates of 16.1% and gastrojejunostomy stenosis rate of 5%. There was one (0.8%) staple line failure which was comparable with that reported by Higa et al. Bleeding was seen in 0.8% which required re-exploration, which was comparable with other literature.,,,
The strengths of this study include a prospectively maintained database, long follow-up. Limitations include a small cohort, retrospective analysis, and limited follow-up rates in the long run.
In conclusion, laparoscopic RYGB is a safe and effective option for weight loss in the short and medium term. Future studies with larger numbers and better follow-up percentages are needed to draw better conclusions.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
Ali M, El Chaar M, Ghiassi S, Rogers AM, American Society for Metabolic and Bariatric Surgery Clinical Issues Committee. American Society for Metabolic and Bariatric Surgery updated position statement on sleeve gastrectomy as a bariatric procedure. Surg Obes Relat Dis 2017;13:1652-7.
Hayoz C, Hermann T, Raptis DA, Brönnimann A, Peterli R, Zuber M. Comparison of metabolic outcomes in patients undergoing laparoscopic roux-en-Y gastric bypass versus sleeve gastrectomy – A systematic review and meta-analysis of randomised controlled trials. Swiss Med Wkly 2018;148:w14633.
Mehaffey JH, LaPar DJ, Clement KC, Turrentine FE, Miller MS, Hallowell PT, et al.
10-year outcomes after roux-en-Y gastric bypass. Ann Surg 2016;264:121-6.
Ismail M, Nagaraj D, Rajagopal M, Ansari H, Iyyankutty K, Nair M, et al.
Is weight regaining significant post laparoscopic Roux-en-Y gastric bypass surgery? – A 5-year follow-up study on Indian patients. J Minim Access Surg 2021;17:159-64.
Reinhold RB. Critical analysis of long term weight loss following gastric bypass. Surg Gynecol Obstet 1982;155:385-94.
Lauti M, Lemanu D, Zeng IS, Su'a B, Hill AG, MacCormick AD. Definition determines weight regain outcomes after sleeve gastrectomy. Surg Obes Relat Dis 2017;13:1123-9.
Liu SY, Wong SK, Lam CC, Yung MY, Kong AP, Ng EK. Long-term results on weight loss and diabetes remission after laparoscopic sleeve gastrectomy for A morbidly obese Chinese population. Obes Surg 2015;25:1901-8.
Brethauer SA, Kim J, el Chaar M, Papasavas P, Eisenberg D, Rogers A, et al.
Standardized outcomes reporting in metabolic and bariatric surgery. Surg Obes Relat Dis 2015;11:489-506.
Cappellini MD, Motta I. Anemia in clinical practice-definition and classification: Does hemoglobin change with aging? Semin Hematol 2015;52:261-9.
Harper J, Madan AK, Ternovits CA, Tichansky DS. What happens to patients who do not follow-up after bariatric surgery? Am Surg 2007;73:181-4.
Bennett JC, Wang H, Schirmer BD, Northup CJ. Quality of life and resolution of co-morbidities in super-obese patients remaining morbidly obese after Roux-en-Y gastric bypass. Surg Obes Relat Dis 2007;3:387-91.
Thereaux J, Lesuffleur T, Païta M, Czernichow S, Basdevant A, Msika S, et al.
Long-term follow-up after bariatric surgery in a national cohort. Br J Surg 2017;104:1362-71.
Stroh C, Weiner R, Wolff S, Knoll C, Manger T, Obesity Surgery Working Group; Competence Network Obesity Influences of gender on complication rate and outcome after Roux-en-Y gastric bypass: Data analysis of more than 10,000 operations from the German Bariatric Surgery Registry. Obes Surg 2014;24:1625-33.
Christou NV, Look D, MacLean LD. Weight gain after short- and long-limb gastric bypass in patients followed for longer than 10 years: Ann Surg 2006;244:734-40.
Homan J, Betzel B, Aarts EO, van Laarhoven KJ, Janssen IM, Berends FJ. Secondary surgery after sleeve gastrectomy: Roux-en-Y gastric bypass or biliopancreatic diversion with duodenal switch. Surg Obes Relat Dis 2015;11:771-7.
Colquitt JL, Pickett K, Loveman E, Frampton GK. Surgery for weight loss in adults. Cochrane Database Syst Rev. 2014;(8):CD003641.
Baig SJ, Priya P, Mahawar KK, Shah S, Indian Bariatric Surgery Outcome Reporting (IBSOR) Group. Weight regain after bariatric surgery – A multicentre study of 9617 patients from Indian bariatric surgery outcome reporting group. Obes Surg 2019;29:1583-92.
Buchwald H, Avidor Y, Braunwald E, Jensen MD, Pories W, Fahrbach K, et al.
Bariatric surgery: A systematic review and meta-analysis. JAMA 2004;292:1724-37.
Gigante DP, de Moura EC, Sardinha LM. Prevalence of overweight and obesity and associated factors, Brazil, 2006. Rev Saúde Pública 2009;43:83-9.
Debédat J, Sokolovska N, Coupaye M, Panunzi S, Chakaroun R, Genser L, et al.
Long-term relapse of type 2 diabetes after Roux-en-Y gastric bypass: Prediction and clinical relevance. Diabetes Care 2018;41:2086-95.
Liu F, Di J, Yu H, Han J, Bao Y, Jia W. Effect of Roux-en-Y gastric bypass on thyroid function in euthyroid patients with obesity and type 2 diabetes. Surg Obes Relat Dis 2017;13:1701-7.
Rudnicki Y, Slavin M, Keidar A, Kent I, Berkovich L, Tiomkin V, et al.
The effect of bariatric surgery on hypothyroidism: Sleeve gastrectomy versus gastric bypass. Surg Obes Relat Dis 2018;14:1297-303.
Kozłowska L, Rosołowska-Huszcz D. Leptin, thyrotropin, and thyroid hormones in obese/overweight women before and after two levels of energy deficit. Endocrine 2004;24:147-53.
Rosenbaum M, Nicolson M, Hirsch J, Murphy E, Chu F, Leibel RL. Effects of weight change on plasma leptin concentrations and energy expenditure. J Clin Endocrinol Metab 1997;82:3647-54.
Rosenbaum M, Murphy EM, Heymsfield SB, Matthews DE, Leibel RL. Low dose leptin administration reverses effects of sustained weight-reduction on energy expenditure and circulating concentrations of thyroid hormones. J Clin Endocrinol Metab 2002;87:2391-4.
Frezza EE, Ikramuddin S, Gourash W, Rakitt T, Kingston A, Luketich J, et al.
Symptomatic improvement in gastroesophageal reflux disease (GERD) following laparoscopic Roux-en-Y gastric bypass. Surg Endosc 2002;16:1027-31.
Perry Y, Courcoulas AP, Fernando HC, Buenaventura PO, McCaughan JS, Luketich JD. Laparoscopic Roux-en-Y gastric bypass for recalcitrant gastroesophageal reflux disease in morbidly obese patients. JSLS 2004;8:19-23.
Fredheim JM, Rollheim J, Sandbu R, Hofsø D, Omland T, Røislien J, et al.
Obstructive sleep apnea after weight loss: A clinical trial comparing gastric bypass and intensive lifestyle intervention. J Clin Sleep Med 2013;9:427-32.
Ali AT, Paiker JE, Crowther NJ. The relationship between anthropometry and serum concentrations of alkaline phosphatase isoenzymes, liver-enzymes, albumin, and bilirubin. Am J Clin Pathol 2006;126:437-42.
Khan AR, Awan FR, Najam SS, Islam M, Siddique T, Zain M. Elevated serum level of human alkaline phosphatase in obesity. J Pak Med Assoc 2015;65:1182-5.
Brolin RE, LaMarca LB, Kenler HA, Cody RP. Malabsorptive gastric bypass in patients with superobesity. J Gastrointest Surg 2002;6:195-203.
Halverson JD. Vitamin and mineral deficiencies following obesity surgery. Gastroenterol Clin North Am 1987;16:307-15.
Kalfarentzos F, Dimakopoulos A, Kehagias I, Loukidi A, Mead N. Vertical banded gastroplasty versus standard or distal Roux-en-Y gastric bypass based on specific selection criteria in the morbidly obese: Preliminary results. Obes Surg 1999;9:433-42.
Skroubis G, Sakellaropoulos G, Pouggouras K, Mead N, Nikiforidis G, Kalfarentzos F. Comparison of nutritional deficiencies after Roux-en-Y gastric bypass and after biliopancreatic diversion with Roux-en-Y gastric bypass. Obes Surg 2002;12:551-8.
Higa K, Ho T, Tercero F, Yunus T, Boone KB. Laparoscopic Roux-en-Y gastric bypass: 10-year follow-up. Surg Obes Relat Dis 2011;7:516-25.
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. Surg Obes Relat Dis 2016;12:11-20.
[Figure 1], [Figure 2]
[Table 1], [Table 2], [Table 3], [Table 4], [Table 5], [Table 6], [Table 7], [Table 8]