Background
Metabolic/bariatric procedures for the treatment of morbid obesity, as well as for type 2 diabetes, are among the most commonly performed gastrointestinal operations today, justifying periodic assessment of the numerical status of metabolic/bariatric surgery and its relative distribution of procedures.

Metabolic/Bariatric Surgery Worldwide 2011

Importance The prevalence of obesity and outcomes of bariatric surgery are well established. However, analyses of the surgery impact have not been updated and comprehensively investigated since 2003. Objective To examine the effectiveness and risks of bariatric surgery using up-to-date, comprehensive data and appropriate meta-analytic techniques. Data Sources Literature searches of Medline, Embase, Scopus, Current Contents, Cochrane Library, and Clinicaltrials.gov between 2003 and 2012 were performed. Study Selection Exclusion criteria included publication of abstracts only, case reports, letters, comments, or reviews; animal studies; languages other than English; duplicate studies; no surgical intervention; and no population of interest. Inclusion criteria were a report of surgical procedure performed and at least 1 outcome of interest resulting from the studied surgery was reported: comorbidities, mortality, complications, reoperations, or weight loss. Of the 25 060 initially identified articles, 24 023 studies met the exclusion criteria, and 259 met the inclusion criteria. Data Extraction and Synthesis A review protocol was followed throughout. Three reviewers independently reviewed studies, abstracted data, and resolved disagreements by consensus. Studies were evaluated for quality. Main Outcomes and Measures Mortality, complications, reoperations, weight loss, and remission of obesity-related diseases. Results A total of 164 studies were included (37 randomized clinical trials and 127 observational studies). Analyses included 161 756 patients with a mean age of 44.56 years and body mass index of 45.62. We conducted random-effects and fixed-effect meta-analyses and meta-regression. In randomized clinical trials, the mortality rate within 30 days was 0.08% (95% CI, 0.01%-0.24%); the mortality rate after 30 days was 0.31% (95% CI, 0.01%-0.75%). Body mass index loss at 5 years postsurgery was 12 to 17. The complication rate was 17% (95% CI, 11%-23%), and the reoperation rate was 7% (95% CI, 3%-12%). Gastric bypass was more effective in weight loss but associated with more complications. Adjustable gastric banding had lower mortality and complication rates; yet, the reoperation rate was higher and weight loss was less substantial than gastric bypass. Sleeve gastrectomy appeared to be more effective in weight loss than adjustable gastric banding and comparable with gastric bypass. Conclusions and Relevance Bariatric surgery provides substantial and sustained effects on weight loss and ameliorates obesity-attributable comorbidities in the majority of bariatric patients, although risks of complication, reoperation, and death exist. Death rates were lower than those reported in previous meta-analyses.

https://jamanetwork.com/journals/jamasurgery/articlepdf/1790378/soi130085.pdf

The effectiveness and risks of bariatric surgery: an updated systematic review and meta-analysis, 2003-2012.

The first global survey of bariatric/metabolic surgery based on data from the nations or national groupings of the International Federation for the Surgery of Obesity and Metabolic Diseases (IFSO) was published in 1998, followed by reports in 2003, 2009, 2011, and 2012. In this survey, we report a global overview of worldwide bariatric surgery in 2013. A questionnaire evaluating the number and the type of bariatric procedure performed in 2013 was emailed to all members of bariatric societies belonging to IFSO. Trend analyses from 2003 to 2013 were also performed. There were 49/54 (90.7 %) responders; 37 of the 49 with national registries. The total number of bariatric procedures performed worldwide in 2013 was 468,609, 95.7 % carried out laparoscopically. The highest number (n = 154,276) was from the USA/Canada region. The most commonly performed procedure in the world was Roux-en-Y gastric bypass (RYGB), 45 %; followed by sleeve gastrectomy (SG), 37 %; and adjustable gastric banding (AGB), 10 %. Most significant were the rise in prevalence of SG from 0 to 37 % of the world total from 2003 to 2013, and the fall in AGB of 68 % from its peak in 2008 to 2013. SG is currently the most frequently performed procedure in the USA/Canada and in the Asia/Pacific regions, and second to RYGB in the Europe and Latin/South America regions. The accuracy of the IFSO-based world survey of procedures would be enhanced if each nation or national group would create a national registry.

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Bariatric Surgery Worldwide 2013.

Objective To quantify the overall effects of bariatric surgery compared with non-surgical treatment for obesity. Design Systematic review and meta-analysis based on a random effects model. Data sources Searches of Medline, Embase, and the Cochrane Library from their inception to December 2012 regardless of language or publication status. Eligibility criteria Eligible studies were randomised controlled trials with ≥6 months of follow-up that included individuals with a body mass index ≥30, compared current bariatric surgery techniques with non-surgical treatment, and reported on body weight, cardiovascular risk factors, quality of life, or adverse events. Results The meta-analysis included 11 studies with 796 individuals (range of mean body mass index at baseline 30-52). Individuals allocated to bariatric surgery lost more body weight (mean difference −26 kg (95% confidence interval −31 to −21)) compared with non-surgical treatment, had a higher remission rate of type 2 diabetes (relative risk 22.1 (3.2 to 154.3) in a complete case analysis; 5.3 (1.8 to 15.8) in a conservative analysis assuming diabetes remission in all non-surgically treated individuals with missing data) and metabolic syndrome (relative risk 2.4 (1.6 to 3.6) in complete case analysis; 1.5 (0.9 to 2.3) in conservative analysis), greater improvements in quality of life and reductions in medicine use (no pooled data). Plasma triglyceride concentrations decreased more (mean difference −0.7 mmol/L (−1.0 to −0.4) and high density lipoprotein cholesterol concentrations increased more (mean difference 0.21 mmol/L (0.1 to 0.3)). Changes in blood pressure and total or low density lipoprotein cholesterol concentrations were not significantly different. There were no cardiovascular events or deaths reported after bariatric surgery. The most common adverse events after bariatric surgery were iron deficiency anaemia (15% of individuals undergoing malabsorptive bariatric surgery) and reoperations (8%). Conclusions Compared with non-surgical treatment of obesity, bariatric surgery leads to greater body weight loss and higher remission rates of type 2 diabetes and metabolic syndrome. However, results are limited to two years of follow-up and based on a small number of studies and individuals. Systematic review registration PROSPERO CRD42012003317 (www.crd.york.ac.uk/PROSPERO).

https://www.bmj.com/content/bmj/347/bmj.f5934.full.pdf

Bariatric surgery versus non-surgical treatment for obesity: a systematic review and meta-analysis of randomised controlled trials

Bariatric Surgery Worldwide

Periodically, the state of bariatric surgery worldwide should be assessed; the most recent prior evaluation was in 2003. An email survey was sent to the leadership of the 36 International Federation for the Surgery of Obesity and Metabolic Disorders nations or national groupings, as well as Denmark, Norway, and Sweden. Responses were tabulated; calculation of relative prevalence of specific procedures was done by weighted averages. Out of a potential 39, 36 nations or national groupings responded. In 2008, 344,221 bariatric surgery operations were performed by 4,680 bariatric surgeons; 220,000 of these operations were performed in USA/Canada by 1,625 surgeons. The most commonlyperformed procedures were laparoscopic adjustable gastric banding (AGB; 42.3%), laparoscopic standard Roux-Y gastric bypass (RYGB; 39.7%), and total sleeve gastrectomies 4.5%. Over 90% of procedures were performed laparoscopically. Comparing the 5-year trend from 2003 to 2008, all categories of procedures, with the exception of biliopancreatic diversion/duodenal switch, increased in absolute numbers performed. However, the relative percent of all RYGBs decreased from 65.1% to 49.0%; whereas, AGB increased from 24.4% to 42.3%. Markedly, different trends were found for Europe and USA/Canada: in Europe, AGB decreased from 63.7% to 43.2% and RYGB increased from 11.1% to 39.0%; whereas, in USA/Canada, AGB increased from 9.0% to 44.0% and RYGB decreased from 85.0% to 51.0%. The absolute growth rate of bariatric surgery decreased over the past 5 years (135% increase), in comparison to the preceding 5 years (266% increase). Bariatric surgery continues to grow worldwide, but less so than in the past. The types of procedures are in flux; trends in Europe vs USA/Canada are diametrically opposed.

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Metabolic/Bariatric Surgery Worldwide 2008

The long-limb Roux-en-Y gastric bypass (LLRYGB) was introduced in 1987 as a salvage operation for inadequate weight loss after a standard Roux-en-Y gastric bypass (RYGB). We report on 53 consecutive patients (44 females) with conversion of a failed RYGB to a LLRYGB performed by a single surgeon between 2002 and 2014. No patient had an ascertainable anatomic abnormality to explain his/her weight regain. LLRYGB revision consisted of a 75-cm to 100-cm alimentary Roux limb and a 75-cm to 100-cm common channel; after 2011, in suitable patients, the Roux limb was lengthened to greater than 250 cm. Average values for weight (lbs) were as follows: pre-original RYGB = 329; lowest measured after RYGB = 196; at time of LLRYGB = 285; and at 1, 2, 3, 4, >5 years post LLRYGB = 225, 207, 199, 197, 195, for a sustained weight loss >90 lbs. Average values for BMI (kg/m2) were as follows: pre-original RYGB = 54.3; lowest measured after RYGB = 32.3; at time of LLRYGB = 47.2; and at 1, 2, 3, 4, >5 years post LLRYGB = 37.1, 34.4, 33.0, 32.8, 31.4, for a sustained BMI reduction >16.5 kg/m2. Zero operative mortality; 3 (5.7%) late deaths; 7 (13.2%) 30-day complications; 33 (62.3%) long-term complications with 23 (43.4%) needing TPN; and 14 (26.4%) requiring operative revision. A salvage LLRYGB procedure can be performed safely and is weight successful, but fraught with long-term nutritional problems and a high necessity for revision. A Roux segment over 250 cm may improve outcomes.

Danette M. Oien

Papers

Metabolic/Bariatric Surgery Worldwide 2011

Metabolic/Bariatric Surgery Worldwide 2008

Revision Roux-en-Y Gastric Bypass to Biliopancreatic Long-Limb Gastric Bypass for Inadequate Weight Response: Case Series and Analysis.

Partial ileal bypass affords protection from onset of type 2 diabetes.