|TO:||Administrative File: CAG-00250R2|
Louis Jacques, MD
Director, Coverage and Analysis Group
Tamara Syrek Jensen, JD
Deputy Director, Coverage and Analysis Group
Jyme Schafer, MD, MPH
Director, Division of Medical and Surgical Services
Joseph Chin, MD, MS
Maria Ciccanti, RN
Lead Medical Officer
Lead Health Policy Analyst
|SUBJECT:||Decision Memorandum for CAG #00250R2|
Bariatric Surgery for the Treatment of Morbid Obesity, Reconsideration for the Inclusion of Laparoscopic Sleeve Gastrectomy
|DATE:||June 27, 2012|
Medicare Administrative Contractors acting within their respective jurisdictions may determine coverage
of stand-alone laparoscopic sleeve gastrectomy (LSG) for the treatment of co-morbid conditions related to obesity in Medicare beneficiaries only when all of the following conditions A-C are satisfied.
- The beneficiary has a body-mass index (BMI) ≥ 35 kg/m2,
- The beneficiary has at least one co-morbidity related to obesity, and
- The beneficiary has been previously unsuccessful with medical treatment for obesity.
The sleeve gastrectomy (SG) involves excision of the lateral aspect of the stomach, leaving a much reduced, lesser-curve based, tubular stomach (Hutter, 2011). When this procedure is performed laparoscopically the term laparoscopic sleeve gastrectomy (LSG) is used. Presently, LSG is commonly used as
a stand-alone approach to bariatric surgery; however, initially, the procedure served to reduce gastric capacity and initiate short-term weight loss while the malabsorptive component of the operation (biliopancreatic diversion) provided the long-term weight loss (Brethauer, 2010). A stand-alone sleeve gastrectomy is sometimes referred to as an isolated sleeve gastrectomy. A laparoscopic approach to sleeve gastrectomy was later developed. There are variations in the detail of the sleeve gastrectomy procedure itself. Although LSG has been gaining popularity over the last few years and the number of bariatric surgery units that offer it is increasing, there is not yet a standard technique for this procedure (Ferrer-Márquez, 2011).
Obesity, defined as a body mass index (BMI) ≥ 30 kg/m2, is recognized as an important risk factor for morbidity and mortality associated with a number of chronic diseases such as heart disease and diabetes (Flegal, 2010). The Centers for Disease Control and Prevention (CDC) reported that obesity rates in the U.S. have increased dramatically over the last 30 years, and obesity is now epidemic in the United States (Kahn, 2009). For adults 60 years and older, the prevalence of obesity is about 37%
among men and 34% among women (NHANES - National Health and Nutrition Examination Survey). Obesity may be further classified according to the National Institutes of Health (NIH):
- Class I Obesity = BMI 30.0-34.9 kg/m²
- Class II Obesity = BMI 35.0-39.9 kg/m²
- Class III (Extreme) Obesity = BMI ≥ 40.0 kg/m²
The prevalence of Class II and III obesity is about 12% among men and 13% among women aged 60 years and older (Flegal, 2010). With the trends in older adults, CMS recognizes the importance of screening and treating obesity and recently provided Medicare coverage for intensive behavioral therapy for obesity
(NCD Manual Section 210.12 http://www.cms.gov/manuals/downloads/ncd103c1_Part4.pdf
Since the life expectancy of individuals with obesity appears statistically comparable to non-obese individuals (over 40 years for both obese and nonobese individuals aged 40 years - Nagai, 2012), the long term benefits and harms of specific treatments and interventions for obesity should be considered. This also allows an opportunity to specifically target the direct effect of obesity on morbidity and disability
(Reuser, 2009). Past research has suggested that bariatric surgery may “resolve or improve CVD [cardiovascular disease] risk factors” (Heneghan, 2011). However, most past systematic reviews have not included stand-alone laparoscopic sleeve gastrectomy (LSG). While the various forms of bariatric surgery may help improve certain health outcomes in some individuals, it is important to remember that the successful management of obesity is multi-pronged, life-long and goes well beyond bariatric surgery alone.
III. History of Medicare Coverage
In 2006, CMS released a final National Coverage Determination (NCD) on Bariatric Surgery for the Treatment of Morbid Obesity (NCD Manual Section 100.1 http://www.cms.gov/manuals/downloads/ncd103c1_Part2.pdf). For Medicare beneficiaries who have a BMI ≥ 35, have at least one co-morbidity related to obesity, and who have been previously unsuccessful with medical treatment for obesity, the following procedures were determined to be reasonable and necessary:
- open and laparoscopic Roux-en-Y gastric bypass (RYGBP);
- laparoscopic adjustable gastric banding (LAGB); and
- open and laparoscopic biliopancreatic diversion with duodenal switch (BPD/DS).
In addition, the NCD stipulates that the above bariatric procedures be covered only when performed at facilities that are: (1) certified by the American College of Surgeons (ACS) as a Level 1 Bariatric Surgery Center or (2) certified by the American Society for Bariatric Surgery as a Bariatric Surgery Center of Excellence (BSCOE) (Program Standards and requirements in effect on February 15, 2006). The 2006
NCD specifically non-covered open vertical banded gastroplasty, laparoscopic vertical banded gastroplasty, open sleeve gastrectomy, laparoscopic sleeve gastrectomy, and open adjustable gastric banding because there was a paucity of evidence to support claims of improved health outcomes from those procedures. In 2009, CMS reconsidered the NCD to include type 2 diabetes mellitus as a comorbidity.
A. Current Consideration
CMS opened this review to determine whether or not laparoscopic sleeve gastrectomy is reasonable and necessary under sections 1862 (a)(1)(A) and/or 1862 (a)(1)(E) of the Act. This analysis is limited to evaluating evidence to determine if LSG for the treatment of Class II and Class III obesity should be included as a covered use in the Bariatric Surgery for Treatment of Morbid Obesity National Coverage Determination (NCD). Since open sleeve gastrectomy is no longer reported on in the literature, we are not considering open sleeve gastrectomy within the scope of this reconsideration, thus it will remain non-covered. In addition, we are limiting our consideration to LSG conducted as a stand-alone bariatric procedure, as the definitive treatment rather than one part of a two stage surgery. We believe that studies of LSG/SG as part of a two stage approach are not directly applicable since the intent of surgery, patient
selection, preparation and subsequent follow-up care are likely different for these individuals. As the American Society for Metabolic and Bariatric Surgery (ASMBS) noted, “the performance of the SG as the first stage of the laparoscopic procedure emerged as a risk reduction strategy for high-risk patients” (ASMBS, 2010). Since LSG is now predominately done as a stand-alone procedure, LSG conducted as part of a planned two-stage surgery is beyond the scope of this analysis and thus shall remain non-covered. LSG that converts to open sleeve gastrectomy is also non-covered.
B. Benefit Category
Medicare is a defined benefit program. An item or service must fall within a benefit category as a prerequisite to Medicare coverage. An item or service must meet one of the statutorily defined benefit categories in the Social Security Act and not otherwise be excluded. Under 1861(s)(1) bariatric surgery qualifies as a(n)
- physician service,
- inpatient Hospital Services, and
- incident to a physician's professional Service.
Thus, bariatric surgery qualifies as a benefit.
Note: This may not be an exhaustive list of all applicable Medicare benefit categories for this item or
IV. Timeline of Recent Activities
|September 30, 2011
||CMS initiates this national coverage analysis. |
|October 30, 2011
||The initial 30-day public comment period closes.
|March 29, 2012
||CMS publishes a proposed decision memorandum.
|June 27, 2012
||CMS publishes the decision memorandum.
V. Food and Drug Administration (FDA) Status
We are not aware of any FDA regulatory determinations on this surgical procedure.
VI. General Methodological Principles
When making national coverage decisions under §1862(a)(1)(A), CMS generally evaluates relevant clinical evidence to determine whether or not the evidence is of sufficient quality to support a finding that an item or service falling within a benefit category is reasonable and necessary for the diagnosis or treatment of illness or injury or to improve the functioning of a malformed body member. The critical appraisal of the
evidence enables us to determine to what degree we are confident that: 1) the specific assessment questions can be answered conclusively; and 2) the intervention will improve health outcomes for patients. An improved
health outcome is one of several considerations in determining whether an item or service is reasonable and necessary.
A detailed account of the methodological principles of study design that the agency utilizes to assess the relevant literature on a therapeutic or diagnostic item or service for specific conditions can be found
in Appendix A. In general, features of clinical studies that improve quality and decrease bias include the selection of a clinically relevant cohort, the consistent use of a single good reference standard, and the blinding of readers of the index test, and reference test results.
Public comments sometimes cite the published clinical evidence and give CMS useful information. Public comments that give information on unpublished evidence such as the results of individual practitioners or patients are less rigorous and therefore less useful for making a coverage determination. Public comments that contain personal health information (PHI) will be redacted and the PHI will not be made available to the public. CMS uses the initial public comments to inform its proposed decision. CMS responds in detail to the public comments on a proposed decision when issuing the final decision memorandum.
In this coverage analysis, we considered evidence for LSG as a planned stand-alone procedure for the
treatment of co-morbid conditions associated with morbid obesity published since the prior decision on bariatric surgery in 2006. Important health outcomes of LSG include mortality and weight loss - these
are less inherently subject to bias or measurement/ascertainment errors. Outcomes such as obesity related co-morbidities, quality of life, reoperation, re-hospitalization and adverse events (such as stroke, myocardial infarction, staple line leaks, and infections) are also important. The time frame for measurement of outcomes is also important. Obesity per se does not appear to significantly reduce life expectancy for individuals aged 40 years, which represents a large proportion of patients undergoing LSG as reflected in the current literature. Obesity has a direct impact on morbidity and disability. Given the invasive, non reversible nature of LSG, the time frame should be sufficiently long to be confident that the benefits outweigh the harms. This is especially relevant to older adults ≥ 65 years since it was reported that “higher weight is not associated with worse health in this age group” (Diehr, 2008).
The optimal time frame to evaluate outcomes after bariatric surgery is not well reflected in the available literature as demonstrated by the variability in time frame reporting. Short term (30-90 day) outcomes have been reported but clearly this time frame is insufficient because after this time period weight could be regained or there may be adverse events from the surgery, thus possibly negating any earlier benefit. Intermediate term (12-18 month) outcomes appear to be more appropriate for non-invasive interventions such as counseling and intensive behavioral therapy, where there is no risk similar to adverse events from surgery and the treatment can easily be repeated if shown to be effective.
For invasive interventions such as bariatric surgery, we suggest that a five year time frame would enhance the ability of patients and their treating physicians to compare LSG outcomes with other bariatric surgery procedures. In support of a longer time frame for outcome evaluation, for bariatric surgery devices, FDA has required post approval studies that report 5 year or 10 year successful weight loss. The FDA convened experts in the field who also noted the importance of 5 year outcomes (Pediatric Advisory Committee, 2005). While these actions are specific to devices, many of the considerations are applicable to the surgical treatment of obesity. Short term, intermediate outcomes such as biometric markers and medication use alone can be useful as secondary outcomes but would not be valid primary outcomes alone, given the main intent of the bariatric surgical procedure.
B. Literature Search
CMS searched PubMed from 2/2006 (date of the last NCD) to 12/2011 using key words sleeve or vertical gastrectomy. LSG is relatively new as a stand-alone procedure as it previously has been done as the first part of a two stage surgery. We initially focused our search on randomized controlled trials (RCTs) that evaluated adults ≥ 65 years. Since no randomized controlled trials in older adults were found, we expanded the search criteria to include all RCTs, large, multisite, prospective observational studies (sample size ≥ 100) on adults < 65 years with outcomes of weight loss after 2 years or longer, adverse events and re-operations, and systematic reviews. Excluded literature included very small observational studies with sample sizes less than 50 cases as they have inherent biases that substantially limit generalizability. Studies with biomarkers and medication use alone as primary outcomes and studies with follow-up of less than 1 year were excluded for the reasons noted above. Abstracts, presentations, articles not written in English were also excluded.
Generally, CMS does not consider price when developing NCDs under 1862(a)(1)(A). Some of the studies included in our review evaluated cost-effectiveness; however, CMS’ analysis did not rely on cost-effectiveness, nor did any cost effectiveness information impact the decision.
C. Discussion of Evidence Reviewed
- Is the evidence sufficient to determine that laparoscopic sleeve gastrectomy improves health outcomes for Medicare beneficiaries who have a BMI ≥ 35 kg/m2, have at least one co-morbidity of obesity and have been previously unsuccessful with medical treatment for obesity?
2. External technology assessment
Colquitt JL, Picot J, Loveman E, Clegg AJ. Surgery for obesity. Cochrane Database Syst Rev 2009;2:CD003641.
In this review, only two RCTs (Himpens, 2006 and Karamanakos, 2008) met inclusion criteria. These studies evaluated weight loss as a health outcome. No LSG RCT evaluated mortality or focused on patients ≥ 65 years of age.
Colquitt and colleagues reported the results of a systematic evidence review “to assess the effects of bariatric surgery for obesity.” Included studies were “RCTs, controlled clinical trials and prospective cohort studies comparing surgical interventions with non-surgical treatment (medical management or no
treatment)” up to August, 2008. The target population included “adults fulfilling the standard definition of obese, i.e. people with a BMI of 30 or over” and “young people who fulfill the definition of obesity for their age, sex and height.” Outcomes included “after at least 12 months follow-up: measures of weight change, fat content (for example body mass index) or fat distribution (for example waist-hip ratio); quality of life, ideally measured using a validated instrument; obesity related co-morbidities (for example diabetes, hypertension).
They reported: “Twenty six studies were included. Three RCTs and three prospective cohort studies compared surgery with non-surgical management, and 20 RCTs compared different bariatric procedures. The risk of bias of many trials was uncertain; just five had adequate allocation concealment. A meta-analysis was not appropriate. Surgery results in greater weight loss than conventional treatment in moderate (body mass index greater than 30) as well as severe obesity. Reductions in co-morbidities, such as diabetes and hypertension, also occur. Improvements in health-related quality of life occurred after two years, but effects at ten years are less clear. Surgery is associated with complications, such as pulmonary embolism,
and some postoperative deaths occurred. Five different bariatric procedures were assessed, but some comparisons were assessed by just one trial. The limited evidence suggests that weight loss following gastric bypass is greater than vertical banded gastroplasty or adjustable gastric banding, but similar to isolated sleeve gastrectomy and banded gastric bypass. Isolated sleeve gastrectomy appears to result in greater weight loss than adjustable gastric banding. Evidence comparing vertical banded gastroplasty with adjustable gastric banding is inconclusive. Data on the comparative safety of the bariatric procedures was limited. Weight loss and quality of life were similar between open and laparoscopic surgery. Conversion
from laparoscopic to open surgery may occur.”
They concluded: “Surgery is more effective than conventional management. Certain procedures produce greater weight loss, but data are limited. The evidence on safety is even less clear. Due to limited evidence and poor quality of the trials, caution is required when interpreting comparative safety and effectiveness.”
Delaet D, Schauer D. Obesity in adults. Clinical Evidence 2011;03(604):1-25.
In this report, the systematic review by Colquit and colleagues appeared to be the main source of evidence on LSG.
Delaet and Schauer reported the results of a systematic evidence review “…to answer the following clinical questions: What are the effects of drug treatments in adults with obesity? What are the
effects of bariatric surgery in adults with morbid obesity?” Outcomes included mortality, weight loss and adverse events. Included studies were RCTs and systematic review up to September, 2010. For LSG, they
reported: [Compared with gastric banding], “Sleeve gastrectomy may be more effective at increasing weight loss at 1 and 3 years (low-quality evidence). [Compared with gastric bypass], Sleeve gastrectomy seems more effective at increasing mean excess-weight loss at 1 to 2 years (moderate-quality evidence).” They noted that “we found no clinically important results from RCTs about sleeve gastrectomy compared with non-surgical treatment, or compared with vertical banded gastroplasty or biliopancreatic diversion in obese people.” They further noted that “we don't know whether sleeve gastrectomy is effective.”
ECRI Institute Health Technology Assessment Information Service. Emerging Technology Evidence
Report: Laparoscopic sleeve gastrectomy for obesity. Plymouth Meeting (PA): ECRI Institute; February 2011. Available at https://www.ecri.org/Documents/TA/Gastrectomy_CER.pdf.Summary at: https://www.ecri.org/Documents/Reprints/Laparoscopic_Sleeve_Gastrectomy_for_Obesity(Managed_Care)_October2011.pdf
All comparative findings were rated inconclusive. Only 2 RCTs (Himpens, 2006 and Karamanakos, 2008) met inclusion and evaluated weight loss as a health outcome. No LSG RCT evaluated mortality or focused on patients ≥ 65 years of age. The ECRI Institute conducted a systematic evidence review on LSG. Included studies were controlled studies published in English up to November, 2010. They identified 21 studies with 2633 patients and reported:
1. “How do clinical efficacy outcomes of LSG compare to other bariatric procedures?
No conclusions are currently possible regarding the comparative clinical efficacy of LSG because of the very small quantity of data, much of which came from small, low-quality studies.
An insufficient amount of evidence for each comparison was available to reach conclusions about how the
effectiveness of LSG compares to other bariatric procedures.”
2. “How do perioperative outcomes of LSG compare to other bariatric procedures?
An insufficient amount of evidence for each comparison was available to reach conclusions about how perioperative outcomes associated with LSG compare to other bariatric procedures.”
3. “How do AE [adverse event] rates for LSG compare to those of other bariatric procedures?
No conclusions can be drawn regarding comparative safety because so few studies reported the same AEs.”
4. “What AEs were reported for LSG?
The overall mortality rate was 0.9 percent for super obese patients and 0.2 percent for morbidly obese patients (including one suicide). The proportion of patients requiring reoperation for any reason was 3.5 percent in the super obese group and 2.3 percent in the morbidly obese group. The most common AE was leaking, which most frequently occurred perioperatively. However, at less than 2 percent, the rate was
low. The other AEs occurred at rates of less than 1 percent overall. Super obese patients had several instances of serious events that were not reported in the lower BMI patients, such as need for ventilator support or development of renal failure.”
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 Technol Assess 2009;13:1-190, 215-357, iii-iv.
In this review, only 2 RCTs (Himpens, 2006 and Karamanakos, 2008) met the authors’ inclusion criteria. These studies evaluated weight loss as a health outcome. No LSG RCT evaluated mortality or focused on patients ≥ 65 years of age.
Picot and colleagues reported the results of a systematic evidence review “to assess the clinical effectiveness and cost-effectiveness of bariatric surgery for obesity.” The population included adult with body mass index (BMI) ≥ 30 kg/m2. Outcomes included “after at least 12 months follow-up:
measures of weight change; quality of life (QoL); perioperative and postoperative mortality and morbidity; change in obesity-related comorbidities; cost-effectiveness.” Included studies were RCTs and controlled studies up to August, 2008.
N.B. Although this evidence review uses the quality adjusted life year (QALY) framework, CMS has not adopted any specific QALY or similar threshold that is necessary for Medicare coverage.
They reported: “a total of 5386 references were identified of which 26 were included in the clinical
effectiveness review: three randomised controlled trials (RCTs) and three cohort studies compared surgery with nonsurgical interventions and 20 RCTs compared different surgical procedures. Bariatric surgery was a more effective intervention for weight loss than non-surgical options. In one large cohort study weight loss was still apparent 10 years after surgery, whereas patients receiving conventional treatment had gained weight. Some measures of QoL improved after surgery, but not others.
After surgery, statistically fewer people had metabolic syndrome and there was higher remission of Type 2 diabetes than in non-surgical groups. In one large cohort study the incidence of three out of six comorbidities assessed 10 years after surgery was significantly reduced compared with conventional therapy. Gastric bypass (GBP) was more effective for weight loss than vertical banded gastroplasty (VBG) and adjustable gastric banding (AGB). Laparoscopic isolated sleeve gastrectomy (LISG) was more effective than AGB in one study. GBP and banded GBP led to similar weight loss and results for GBP versus LISG and VBG versus AGB were equivocal. All comparisons of open versus laparoscopic surgeries found similar weight losses in each group. Co-morbidities after surgery improved in all groups, but with no significant differences between different surgical interventions. Adverse event reporting varied; mortality ranged from none to 10%. Adverse events from conventional therapy included intolerance to medication, acute cholecystitis and gastrointestinal problems. Major adverse events following surgery, some necessitating reoperation, included anastomosis leakage, pneumonia, pulmonary embolism, band slippage and band erosion.
Bariatric surgery was cost-effective in comparison to non-surgical treatment in the reviewed published
estimates of cost-effectiveness. However, these estimates are likely to be unreliable and not generalisable because of methodological shortcomings and the modeling assumptions made. Therefore a new economic model was developed. Surgical management was more costly than non-surgical management in each of the three patient populations analysed, but gave improved outcomes. For morbid obesity, incremental cost-effectiveness ratios (ICERs) (base case) ranged between £2000 and £4000 per quality adjusted life year (QALY) gained. They remained within the range regarded as cost-effective from an National Health Service (NHS) decision-making perspective when assumptions for deterministic sensitivity analysis were changed. For BMI ≥ 30 and < 40, ICERs were £18,930 at two years and £1397 at 20 years, and for BMI ≥ 30 and < 35, ICERs were £60,754 at two years and £12,763 at 20 years. Deterministic and probabilistic sensitivity analyses produced ICERs which were generally within the range considered cost-effective, particularly at the long twenty year time horizons, although for the BMI 30-35 group some ICERs were above the acceptable range.”
They concluded: “Bariatric surgery appears to be a clinically effective and cost-effective intervention for moderately to severely obese people compared with non-surgical interventions. Uncertainties remain and further research is required to provide detailed data on patient QoL; impact of surgeon experience on outcome; late complications leading to reoperation; duration of comorbidity remission; resource use. Good-quality RCTs will provide evidence on bariatric surgery for young people and for adults with class I or class II obesity. New research must report on the resolution and/or development of comorbidities such as Type 2 diabetes and hypertension so that the potential benefits of early intervention can be assessed.”
Klarenbach S, Padwal R, Wiebe N, Hazel M, Birch D, Manns B, Karmali S, Sharma A,
Tonelli M. Bariatric Surgery for Severe Obesity: Systematic Review and Economic Evaluation [Internet]. Ottawa: Canadian Agency for Drugs and Technologies in Health; 2010 (Technology report;no. 129). [cited 2010-09-20]. Available from: http://www.cadth.ca/en/publication/2667
Padwal R, Klarenbach S, Wiebe N, Birch D, Karmali S, Manns B, Hazel M, Sharma AM, Tonelli M. Bariatric surgery: a systematic review and network meta-analysis of randomized trials. Obes Rev 2011;12:602-21. doi:
10.1111/j.1467-789X.2011.00866.x. Epub 2011 Mar 28.
Klarenbach and colleagues reported the results of a systematic evidence review “to assess the evidence on clinical effectiveness and safety, and the economic implications of using different bariatric surgery methods in adult patients with severe obesity, as compared with standard care (i.e., lifestyle modification: diet and exercise medical counseling) with or without pharmacological therapy.” The target population included “severely obese adults (16 years or older), with an accepted indication for bariatric surgery: BMI of 40 kg/m2 or more (or BMI of 35 kg/m2 or more with at least one obesity-related comorbidity).” Outcomes included “weight change (primary outcome), all-cause mortality, control of comorbidities, medication burden, hospitalization, health-related quality of life (QoL), excision of redundant tissue after weight loss (body contouring), joint operations, reoperations, gastrointestinal disturbances, and surgical sequelae.” Included studies were quasi-randomized trials or RCTs up to February, 2009.
They reported: “We identified 63 trials. Four trials compared a form of bariatric surgery to standard care, 31 compared one form of bariatric surgery to another form of bariatric surgery, and the remaining assessed a variant of a bariatric surgery. At one year, network analysis was used to rank the effectiveness in reducing BMI (from most to least efficacious): jejunoileal bypass, loop gastric bypass, mini-gastric bypass, BPD, sleeve gastrectomy, RYGB, horizontal gastroplasty (HG), vertical banded gastroplasty, adjustable gastric banding (AGB), and standard care. The results of network analysis at two and three to five years were similar. Of these procedures, sleeve gastrectomy, RYGB, and AGB are commonly performed in contemporary practice. The remaining procedures are uncommonly performed (e.g., BPD) or have been abandoned. Direct evidence supported mixed evidence findings for AGB compared with RGYB (direct evidence at one year: mean difference [MD] 5.8 kg/m2 [95% CI: 1.9 to 9.7]; at two years: 7.2 kg/m2 [5.5 to 8.9]; at three years to five years: 6.4 kg/m2 [4.9 to 7.9]). Direct evidence for sleeve gastrectomy did not show significant differences compared with other procedures or was unavailable. AGB was associated with a higher risk of slippage or dilation (risk difference [RD] 6.1% [1.3 to 11]) and procedure conversion or reversals (RD 8.3% [2.8 to 14]), and a lower risk of stenosis (RD 15% [8.3 to 22]), ulceration (RD 9.9% [4.0 to 16]), herniation (RD 4.5% [0.5 to 8.4]), and wound infection (RD 6.3% [1.4 to 11]) compared with RYGB. AGB was associated with shorter lengths-of-stay compared with RYGB (MD 1.7 days [1.3 to 2.0]).”
They concluded: “The clinical review of effectiveness and safety found that although data from large,
adequately powered, long-term RCTs are lacking, bariatric surgery seems to be more effective than standard care for the treatment of severe obesity in adults. Procedures that are mainly diversionary (for example, BPD) result in the greatest amounts of weight loss, hybrid procedures are of intermediate effectiveness (for example, RYGB), and restrictive procedures (for example, AGB) result in the least amounts of weight loss.
RYGB and AGB tended to lead to trade-offs between the risk of adverse events and the need for procedure
conversion or reversals. For sleeve gastrectomy, the evidence base was limited. The volume-outcome review found that higher surgical volumes were associated with better clinical outcomes. We were unable to identify thresholds for surgical volume that were associated with better clinical outcomes.”
In this review, only 1 RCT (Karamanakos, 2008) met inclusion criteria. This study evaluated weight loss as a health outcome. No LSG RCT evaluated mortality or focused on patients ≥ 65 years of age.
Walsh J. Sleeve gastrectomy as a stand alone bariatric procedure for obesity. California
Technology Assessment Forum. October 13,2010. Available at http://www.ctaf.org/content/assessment/detail/1210.
Walsh reported the results of a technology assessement on sleeve gastrectomy “review the scientific evidence for the use of sleeve gastrectomy (SG) also known as vertical sleeve gastrectomy (VSG) or laparoscopic sleeve gastrectomy (LSG) as a stand-alone surgical treatment for the treatment of obesity.” The assessment evaluated the following 5 criteria as typical of the CTAF approach:
- The technology must have final approval from the appropriate government regulatory bodies - Criterion 1 is met.
- The scientific evidence must permit conclusions concerning the effectiveness of the technology regarding health outcomes. - Criterion 2 is met.
- The technology must improve net health outcomes - Criterion 3 is not met.
- The technology must be as beneficial as any established alternatives - Criterion 4 is not met.
- The improvement must be attainable outside the investigational settings - Criterion 5 is not met.
The author concluded:
“Bariatric surgery might be indicated for individuals who are unable to control their weight with conservative measures. The current standards of care for bariatric surgery are the RYGB and LGB. SG was initially used as the first part of a two part procedure, but subsequent information has suggested that SG alone may be enough for some individuals. SG is technically easier than RYGB and so is an attractive surgical option especially in morbidly obese patients.
The results of multiple case series and retrospective studies have suggested that SG as a primary procedure is associated with a significant reduction in excess weight loss. The complication rate ranged from 0-4.1% and complications included leaks, bleeding, strictures and mortality.
Only two randomized controlled trials have compared SG to another surgical procedure. These trials included a total of 112 participants who were followed from one to three years. Among the 80 participants followed for three years, there were a similar number of complications in the SG and the RYGB groups, although the complications in the SG group were more severe. To date, long term outcomes from registry studies are relatively limited, but longer term follow-up will provide additional important information.”
3. Internal technology assessment
Birkmeyer NJ, Dimick JB, Share D, Hawasli A, English WJ, Genaw J, Finks JF, Carlin AM, Birkmeyer JD;
Michigan Bariatric Surgery Collaborative. Hospital complication rates with bariatric surgery in Michigan. JAMA 2010;304:435-42.
Birkmeyer and colleagues reported the results of an analysis of the Michigan Bariatric Surgery Collaborative registry “to assess complication rates of different bariatric procedures and variability in rates of serious complications across hospitals and according to procedure volume and center of excellence (COE) status.” The registry contains data voluntarily submitted from 25 hospitals that perform at
least 25 bariatric procedures per year. All patients undergoing bariatric surgery from June 2006 to September 2009 (n = 15,275) were included. Patients undergoing revisional surgery and duodenal switch procedures were excluded. Main outcome was 30 day complication rate. Long term outcomes were not evaluated. It was unclear if outcomes data were independently adjudicated. Median age was 46 years. There were no reported patients ≥ 60 years. Median BMI was 46 kg/m2. Men comprised 21% of the population. There were 854 sleeve gastrectomy (SG) procedures. The proportion of SGs that were single stand-alone procedures was not reported. There was no reported control group.
The authors reported: “Overall, 7.3% of patients experienced perioperative complications, most of which were wound problems and other minor complications. Serious complications were most common after gastric bypass (3.6%; 95%confidence interval [CI], 3.2%-4.0%), followed by sleeve gastrectomy (2.2%; 95% CI, 1.2% - 3.2%), and laparoscopic adjustable gastric band (0.9%; 95% CI, 0.6% - 1.1%) procedures (P< .001). Mortality occurred in 0.04% (95% CI, 0.001%-0.13%) of laparoscopic adjustable gastric band, 0 sleeve gastrectomy, and 0.14% (95% CI, 0.08% - 0.25%) of the gastric bypass patients.” They concluded: “The frequency of serious complications among patients undergoing bariatric surgery in Michigan was relatively low. Rates of serious complications are inversely associated with hospital and surgeon procedure volume, but unrelated to COE accreditation by professional organizations.”
DeMaria EJ, Pate V, Warthen M, Winegar DA. Baseline data from American Society for Metabolic and
Bariatric Surgery-designated Bariatric Surgery Centers of Excellence using the Bariatric Outcomes Longitudinal Database. Surg Obes Relat Dis 2010;6:347-55. Epub 2010.
DeMaria and colleagues reported the results of an analysis of the Bariatric Outcomes Longitudinal Database (BOLD), “a registry of self-reported bariatric surgery patient information from the American Society for Metabolic and Bariatric Surgery Bariatric Surgery Center of Excellence participants” to describe baseline characteristics and initial outcomes. Long term outcomes were not evaluated. From June 2007 to May 2009, data from 57,918 patients were submitted by over 450 facilities. Mean age was about 47 years (5.67% were > 65 years). Men comprised 21% of the population. Mean BMI was about 46 kg/m2. There were 1328 SG procedures. The proportion of SGs that were single stand-alone procedures was not reported. It was unclear if outcomes data were independently adjudicated. There was no reported control group. The author reported: “Through May 2009, 78 deaths were reported at any point after the index procedure, for a mortality rate of .13%. The 90-day mortality rate was .11%, and the 30-day mortality rate was .09%.” Data by procedures were not reported. Data for older adults were not presented separately.
Helmiö M, Victorzon M, Ovaska J, Leivonen M, Juuti A, Jaser N, Peromaa P, Tolonen P, Hurme S, Salminen P. SLEEVEPASS: A randomized prospective multicenter study comparing laparoscopic sleeve gastrectomy and gastric bypass in the treatment of morbid obesity: preliminary results. Surg Endosc. 2012 Apr 5. [Epub ahead of print]
Helmio and colleagues reported the results of a randomized trial “to determine the preliminary 30-day morbidity and mortality of RYGB and SG” at a single center in Finland. A total of 240 obese patients
were randomized to undergo either RYGB (n=117) or SG (n=121). Primary outcomes were 30 day mortality and
morbidity which included bleeding, infections, bowel perforations. Inclusion criteria were: “(1) BMI ≥40 or BMI ≥35 with a significant comorbidity associated with morbid obesity (type 2 diabetes, hypertension, obstructive sleep apnea, dyslipidemia, and arthrosis), (2) age = 18–60 years, and (3) previous successfully instituted and supervised but failed adequate diet and exercise program. Median age was 49 years (range 23-67). Men comprised 30% of the study population. Median pre-operative BMI was about 45 kg/m2. The authors reported no 30 day mortality and 30 day morbidity that did not differ significantly between groups. They concluded: “At 30-day analysis SG is associated with a shorter operating time and fewer early minor complications compared to RYGB. There were no significant differences in major
complications or early reoperations. Long-term follow-up is required to determine the effect on weight loss, resolution of obesity-related comorbidities, and improvement of quality of life.”
Himpens J, Dapri G, Cadière GB. A prospective randomized study between laparoscopic gastric banding
and laparoscopic isolated sleeve gastrectomy: results after 1 and 3 years. Obes Surg 2006 Nov;16:1450-6.
Himpens and colleagues reported the results of a randomized trial “to compare the laparoscopic adjustable GB (LGB, also referred to as LAGB) and laparoscopic isolated SG in terms of weight loss, feeling of hunger,
craving for eating sweets, gastroesophageal reflux disease (GERD), complications and re-operations, reporting the results after 1 year and 3 years.” Eighty patients were randomized to LGB (n = 40) or LSG (n = 40). Inclusion criteria were not reported. Outcomes included weight loss and adverse events. Univariate Chi-square and Mann-Whitney tests were used for the analyses. Median age was 36 years (LGB) and 40 years (LSG). Gender was not reported. Median BMI was 37 for LGB versus 39 for LSG. The authors reported: “Median weight loss after 1 year was 14 kg (-5 to + 38) for GB and 26 kg (0 to 46) for SG (P < 0.0001); and after 3 years was 17 kg (0 to 40) for GB and 29.5 kg (1 to 48) for SG (P < 0.0001). Median decrease in BMI after 1 year was 15.5 kg/m2 (5 to 39) after GB and 25 kg/m2 (0 to 45) after SG (P < 0.0001); and after 3 years was 18 kg/m2 (0 to 39) after GB and 27.5 kg/m2 (0 to 48) after SG (P = 0.0004).” They concluded: “Weight loss and loss of feeling of hunger after 1 year and 3 years are better after SG than GB. GERD is more frequent at 1 year after SG and at 3 years after GB. The number of re-operations is important in both groups, but the severity of complications appears higher in SG.”
Hutter MM, Schirmer BD, Jones DB, Ko CY, Cohen ME, Merkow RP, Nguyen NT. First report from the American College of Surgeons Bariatric Surgery Center Network: laparoscopic sleeve gastrectomy has morbidity and effectiveness positioned between the band and the bypass. Ann Surg 2011;254:410-20.
Hutter and colleagues reported the results of an analysis of the American College of Surgeons Bariatric Surgery Center Network (ACS-BSCN) Accreditation Program “to assess the safety and effectiveness of the
laparoscopic sleeve gastrectomy (LSG) as compared to the laparoscopic adjustable gastric band (LAGB), the laparoscopic Roux-en-Y gastric bypass (LRYGB) and the open Roux-en-Y gastric bypass (ORYGB) for the treatment of obesity and obesity related diseases.”
The ACS-BSCN “accredits facilities in the United States that have undergone an independent, voluntary and rigorous peer evaluation in accordance with nationally recognized bariatric surgical standards.” Outcomes included “30-day, 6-month, and 1-year outcomes including morbidity and mortality, readmissions, and reoperations as well as reduction in body mass index (BMI) and weight-related co-morbidities.” Long term outcomes were not evaluated. It was unclear if outcomes data were independently adjudicated. From July 2007 to September 2010, data on 28,616 patients were voluntarily submitted by 190 hospitals. There were
944 LSG procedures. There was no control group. Of these, mean age was about 47 years (5.93% were ≥ 60 years). Men comprised about 25% of the population. Mean BMI was about 46 kg/m2. Data for older adults were not presented separately.
The authors reported: “The LSG has higher risk-adjusted morbidity, readmission and reoperation/intervention rates compared to the LAGB, but lower reoperation/intervention rates compared to the LRYGB and ORYGB. There were no differences in mortality. Reduction in BMI and most of the weight-related co-morbidities after the LSG also lies between those of the LAGB and the LRYGB/ORYGB.” They concluded: “LSG has morbidity and effectiveness positioned between the LAGB and the LRYGB/ORYGB for data up to 1 year. As obesity is a lifelong disease, longer term comparative effectiveness data are most critical,
and are yet to be determined.”
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. Ann Surg 2008;247:401-7.
Karamanakos and colleagues reported the results of a randomized clinical trial “to evaluate and compare the effects of laparoscopic Roux-en-Y gastric bypass (LRYGBP) with laparoscopic sleeve gastrectomy (LSG) on body weight, appetite, fasting, and postprandial ghrelin and peptide-YY (PYY) levels.” Inclusion and exclusion criteria were not reported. A total of 32 patients were randomly assigned to LRYGBP (n = 16) or LSG (n = 16). Measurements were recorded at months 1, 3, 6, and 12 postoperatively. Univariate Student t test was used for the analyses. Mean age was about 34 years. Men comprised about 16% of the study population. Mean baseline BMI was about 45 kg/m2.
They reported: “Body weight and body mass index (BMI) decreased markedly (P < 0.0001) and comparably after either procedure. Excess weight loss was greater after LSG at 6 months (55.5% +/- 7.6% vs. 50.2% =/- 6.5%, P = 0.04) and 12 months (69.7% =/- 14.6% vs. 60.5% =/- 10.7%, [P= 0.05]).” They concluded: “PYY levels increased similarly after either procedure. The markedly reduced ghrelin levels in addition to increased PYY levels after LSG are associated with greater appetite suppression and excess weight loss compared with LRYGBP.”
Nienhuijs SW, de Zoete JP, Berende CA, de Hingh IH, Smulders JF. Evaluation of laparoscopic sleeve
gastrectomy on weight loss and co-morbidity. Int J Surg. 2010;8(4):302-4. Epub 2010 Mar 19.
The authors reported the results of a case series of 74 patients who received LSG to evaluate weight loss and co-morbidity. Procedures were performed at one center in the Netherlands from about 2006-2008. Inclusion criteria were not specifically reported. Median age was 42 years (range 16-66). Median BMI was 51 (range 35-94). Median postoperative follow up was 12 months. The authors reported median percentage of excess weight loss was 49.6%. Of the 74 patients, 16 (22%) had postoperative complications.
The authors concluded: “In summary, the laparoscopic sleeve gastrectomy is effective in reduction of weight and co-morbidity. When the complication rate decreases with experience, it can be regarded as a safe technique. Therefore, patient’s selection is recommendable for initial surgical experience. With a shorter operative time and less postoperative complications it has the possibilities to replace the gastric bypass as the standard treatment for patients suffering from morbid obesity. Supposedly, more benefits could be revealed as a result food follows the physiological route. Furthermore, the possibility remains available to convert a sleeve gastrectomy into a gastric bypass in cases of weight reducing failures. On the other
hand, the present results were only of short term nature and other long follow-up data are lacking yet, there are possibilities of regaining weight after a sleeve gastrectomy, dilatation of the pouch and complications following re-intervention. So, the gastric bypass remains the gold standard and long follow-up after sleeve gastrectomy is necessary.”
Schauer PR, Kashyap SR, Wolski K, Brethauer SA, Kirwan JP, Pothier CE, Thomas S, Abood B, Nissen
SE, Bhatt DL. Bariatric surgery versus intensive medical therapy in obese patients with diabetes. N Engl J Med 2012 Apr 26;366(17):1567-76.
Schauer and colleagues reported the results of a single center, randomized trial “to compare intensive medical therapy with surgical treatment (gastric bypass or sleeve gastrectomy) as a means of improving
glycemic control in obese patients with type 2 diabetes.” One hundred and fifty obese patients with
uncontrolled diabetes were randomized to receive intensive medical therapy alone (n = 43) or with either Roux-en-Y gastric bypass (n = 50) or sleeve gastrectomy (n = 49) at a single center in the U.S. Primary outcome was glycated hemoglobin level of 6.0% or less at 12 months. Inclusion criteria included BMI 27-43, aged 20-60 years and glycated hemoglobin level > 7.0%. Mean age was 49 years. Men comprised 34% of the participants. Mean BMI was about 36 with 34% having a BMI < 35.
The authors reported “[t]h proportion of patients with the primary end point was 12% (5 of 41 patients) in the medical therapy group versus 42% (21 of 50 patients) in the gastric-bypass group (P = 0.002) and 37%
(18 of 49 patients) in the sleeve-gastrectomy group (P = 0.008).” Numbers of adverse events per group were
18.6% (8/43), 52% (26/50) and 22.4% (11/49), respectively.
The authors concluded: “In obese patients with uncontrolled type 2 diabetes, 12 months of medical therapy plus bariatric surgery achieved glycemic control in significantly more patients than medical therapy alone. Further study will be necessary to assess the durability of these results.” Bariatric procedures were performed laparoscopically by a single surgeon at a single site. The number of patients that withdrew was higher in the medical therapy group (7 versus 1 in the LSG group). Long term follow-up was not available.
Stroh C, Weiner R, Horbach T, Ludwig K, Dressler M, Wolff S, Lippert H, Büsing M, Schmidt U,
Manger T. Results of sleeve gastrectomy in Germany—Data on Nationwide Survey on quality assurance in bariatric surgery in Germany. Surgical Science, 2012, 3, 169-176.
Stroh and colleagues reported the results of an analysis of 1478 laparoscopic sleeve gastrectomies performed at 45 hospitals in Germany from 2006-2009. The data were obtained from the Nationwide Survey on bariatric surgery, a voluntary registry, but all certified centers of bariatric surgery in Germany have to contribute. Mean age of patients was about 43 years (range not reported). Mean BMI was 53 kg/m2. Mean follow up time was not reported but bariatric data have been reported since 2005, LSG since 2006. The authors reported 9 reported deaths (0.6%). Leak rate was about 3%. The authors concluded: “SG is a common and hype bariatric procedure in Germany, but postoperative complication rate is high. Data on the long-term effect of SG on weight loss and amelioration of comorbidities need to be
evaluated. More detailed analyzes are necessary to establish the position of SG in the bariatric surgery. Further studies should also include examinations on long-term complications and redo-procedure after SG.”
The MEDCAC was not convened for this review.
5. Evidence-based guidelines
An Internet-based search of www.guideline.gov (i.e., the National Guideline Clearinghouse) using the search terms “sleeve gastrectomy,” “bariatric surgery,” or “obesity” did not reveal any LSG surgery-specific guidelines. The SAGES guideline for clinical application of laparoscopic bariatric surgery was found during the search. While the SAGES guidelines provided guidelines for specific bariatric surgeries (LBPD +\-
DS, RGB, and AGB) it didn’t include guidelines for LSG. Instead, it included this statement: “LSG is validated as providing effective weight loss and resolution of comorbidities to 3 to 5 years (level II, grade C). The VA/DoD clinical practice guideline for screening and management of overweight and obesity was returned in the search; however, it did not include LSG in its bariatric surgery recommendations and
stated, “there is insufficient evidence to recommend for or against the routine use of bariatric surgery in those over 65 years of age and patients with a substantial surgical risk”. In addition, there were guidelines for the prevention and management of obesity (http://www.healthquality.va.gov/obesity/obe06_final1.pdf).
6. Professional Society Position Statements
American Society for Metabolic & Bariatric Surgery. Updated Position Statement on Sleeve Gastrectomy as a Bariatric Procedure. 2011. Available at: http://s3.amazonaws.com/publicASMBS/GuidelinesStatements/PositionStatement/ASMBS-SLEEVE-STATEMENT-2011_10_28.pdf.
The American Society for Metabolic and Bariatric Surgery (ASMBS) posted an update of their position statement:
Summary and Recommendations.
“Substantial comparative and long-term data are now published in the peer-reviewed literature demonstrating durable weight loss, improved medical comorbidities, long-term patient satisfaction, and improved quality of life after SG. The ASMBS therefore recognizes SG as an acceptable option as a primary bariatric procedure and as a first stage procedure in high risk patients as part of a planned staged approach."
“Based on the current published literature, SG has a risk/benefit profile that lies between the laparoscopic adjustable gastric band and the laparoscopic Roux-en-Y gastric bypass. As with any bariatric procedure, long-term weight regain can occur and, in the case of SG, this could be managed effectively with re-intervention. Informed consent for SG used as a primary procedure should be consistent with consent provided for other bariatric procedures and should include the risk of long-term weight gain. Surgeons performing SG are encouraged to continue to prospectively collect and report outcome data in the peer-reviewed scientific literature.”
This update was posted on the ASMBS site but has not yet been published in a peer reviewed journal. Long term data were extracted from 6 single site observational studies all with small sample sizes (n < 50), high loss to follow-up (20 - 90%) and/or high rate of revisional surgery (> 20%).
7. Expert Opinion
Except as may be noted elsewhere in this memorandum, we have not received expert opinion on this issue.
8. Public Comments
Initial 30 day comment period
CMS received 180 timely public comments. One hundred seventy-nine of them supported the inclusion of LSG as a covered surgery in the bariatric surgery NCD. There were no comments specifically about CED. Comments can be viewed on the CMS website (http://www.cms.gov/medicare-coverage-database/details/nca-view-public-comments.aspx?NCAId=258&ExpandComments=n&NcaName=Bariatric+Surgery+for+the+Treatment+of+Morbid+Obesity+(2nd+Recon)&bc=ACAAAAAAIAAA&
Public Comment Period on the Proposed Decision: 03/29/2012 – 04/28/2012
CMS received 421 public comments on the proposed decision memorandum. Over half of the comments were copies of a form letter claiming that proposed decision memo had an incomplete review of available evidence, did not consider the entire Medicare population, and will diminish access to care for patients. In addition, the form letter cited four studies which will be addressed below. The form letter did not include a response to CMS’ proposal for coverage with evidence development or the proposed sunset provision. Most of the form letters were submitted by commenters involved in the business or care of bariatric surgery patients.
Three comments supported CMS’ proposed decision memorandum: two of these were from bariatric surgeons and one was from a manufacturer of a gastric band device. In general, all three supporting commenters agreed that while short term outcomes were available, there are insufficient medium and long term data. The remaining 418 commenters did not support the proposed decision. None of the comments expressed an interest or plan to develop a clinical trial, though one commenter stated, “ if CMS does proceed with its plans to restrict Medicare coverage of sleeve gastrectomy to patients enrolled in a trial, our group would be well positioned to participate.”
One commenter noted: (1) there are no high quality studies or randomized controlled trials that specifically address the use of LSG in Medicare-eligible patients, (2) the absence of such studies requires the generalization of data regarding younger adults to an older population, which may not be clinically appropriate, and (3) no published study (regardless of study population demographics) reported long-term outcomes with an adequate number of participants.
CMS partially agrees with the comment. The Medicare beneficiary population is diverse. Though the vast majority of our beneficiaries qualify based on advanced age, there are younger beneficiaries whose eligibility is based on chronic disability from various causes or on end stage renal disease being treated with dialysis. We have become aware since the publication of our proposed decision of new evidence reporting LSG outcomes in younger patients. We agree with the commenter that long term outcomes have not been reported.
Another commenter stated that his patients experienced weight regain after 5 years and expressed concern
about sleeve recidivism. Another commenter stated, “intuitively this operation will be associated with regain of most of the weight lost.”
We are not aware of any published long term data that would refute the commenter’s anecdotal assertion.
A form letter, submitted by over half the commenters, cited four studies as additional evidence, asserting that CMS did not consider these when developing the proposed decision memorandum. The studies are:
- Himpens, J et al. Long-term Results of Laparoscopic Sleeve Gastrectomy for Obesity. Ann Surg 2010;252: 319–324,
- O’Keefe, K et al. Bariatric Surgery Outcomes in Patients Aged 65 Years and Older at an American Society for Metabolic and Bariatric Surgery Center of Excellence. Obes Surg (2010) 20:1199–1205,
- Leonetti, F et al. Obesity, Type 2 Diabetes Mellitus, and Other Comorbidities: A Prospective Cohort Study of Laparoscopic Sleeve Gastrectomy vs. Medical Treatment. [published online ahead of print April 16, 2012]. Arch Surg. doi:10.1001/archsurg.2012.222,
- Schauer, P et al. Bariatric Surgery versus Intensive Medical Therapy in Obese Patients with Diabetes. N Engl J Med 2012; 366:1567-1576.
The original study by Himpens was included in our initial analysis and a follow up publication. A later report, referenced in the form letter, was published evaluating the six year durability of the three year randomized sleeve gastrectomy results. However, the persuasiveness of the study was limited by incomplete follow-up due to lack of data on 23 of the original 53 patients in the study. This absence of data on over one-third of the subjects is a significant weakness and we believe it creates significant
uncertainty about the authors’ conclusions.
The study by O’Keefe and colleagues did not meet our inclusion criteria since only six of the subjects were reported to have received LSG. This number is too small to give us confidence that the authors’ conclusions can be generalized to beneficiaries who would receive LSG.
The study by Leonetti did not meet our inclusion criteria on health outcomes due to its limited sample size for an observational study and use of biometric primary outcomes.
The study by Schauer was in fact included in our review in the proposed decision memorandum. While the study was encouraging, it does not include the Medicare aged population and we are not confident it represents the Medicare disabled population.
CMS received nine other references in the public comments and reviewed each study.
Of these, seven did not meet our review inclusion criteria because of inadequate sample size or reliance on limited primary outcomes such as biometric markers alone. Two studies (Nienhuijs, 2010; Stroh, 2009) were added to our review. Nienhuijs 2010 is a case series of 74 patients in the Netherlands from 2006-2008, median age of 42. One of the conclusions is “...When the complication rate decreases with experience, it can be regarded as a safe technique.” Stroh 2012 is a registry report from 45 hospitals in Germany from 2006-2009, with mean age of 43 years. One of the conclusions is that the postoperative complication rate is high and that data on the long-term effect on weight loss and amelioration of comorbidities need to be evaluated.
The majority of commenters did not support CED for LSG. Some stated they believed that requiring a
clinical trial is redundant, cost-ineffective and in conflict with CMS published standard of scientific integrity and relevance. Others noted that randomized clinical trials (RCTs) may work when refining a technique for the same surgery, but is difficult to do to compare medical management to a surgery. Several commenters asserted that requiring CED as a condition of coverage results in disparity of care.
Although CMS proposed CED, as explained in the analysis section of this decision memorandum, we believe coverage of stand-alone LSG in patients with the three clinical criteria described in our proposed decision: a body-mass index (BMI) of ≥ 35 kg/m2, at least one co-morbidity related to obesity, and previous lack of success with medical treatment for obesity, should be determined by our local administrative contractors, who are in a better position to consider characteristics of individual beneficiaries and the performance of bariatric surgery facilities within their jurisdictions.
Several commenters stated that the decision was focused on Medicare beneficiaries 65 years old and older and that many Medicare beneficiaries less than 65 years old have co-morbidities that would benefit from LSG. Some providers indicated that they do not perform LSG on patients older than 65. Others stated that Medicare patients have the highest morbidity of any other patients and would benefit from LSG.
Additional evidence persuades us that LSG could possibly improve health outcomes for carefully selected Medicare beneficiaries, however, we do not believe that the current evidence base supports a broad positive coverage determination for all Medicare beneficiaries. As we note above, the beneficiary population is diverse; younger beneficiaries inherently have other medical conditions that are sufficiently burdensome to cause permanent disability or the need for chronic dialysis.
In our proposed decision, the evidence for CED was entirely comprised of studies enrolling younger adult subjects. With inclusion of the trial by Schauer, the evidence again supported LSG for younger adults who met the trial inclusion and exclusion criteria. This allowed a more complete evaluation of the characteristics of the study participants, but we did not find direct evidence that any trial subjects with chronic disability or ESRD requiring dialysis (which would support generalizability to younger Medicare
beneficiaries) were enrolled. The trial by Schauer was given greater evidentiary weight in the consideration since it was a randomized controlled trial and recently performed at an academic center in the U.S. with support from the NIH.
Several commenters listed clinical criteria for which they believe LSG is more appropriate than other
bariatric surgeries currently covered by Medicare. Some of the patient characteristics they listed
included inability to tolerate supplements, the need to be maintained on non-steroidal medications, and transplant patients who require more absorption of anti-rejection medications.
CMS is unaware of any methodologically robust studies evaluating broad patient selection strategies for patient allocation among various bariatric surgery options.
Several commenters stated that the laparoscopic adjustable gastric banding (LAGB) currently covered by Medicare has a very high failure rate and is currently covered by Medicare. These commenters wondered why CMS continues to cover this procedure yet had proposed CED for LSG.
While coverage of LAGB is outside the scope of this review, CMS appreciates being notified of treatments that are alleged to be harmful or ineffective.
Some commenters stated that Medicare has already required center of excellence programs, which are capturing data through the Bariatric Outcomes Longitudinal Database (BOLD) and the Bariatric Surgery Center Network (BSCN) database, and should use those data to make an unrestricted determination of LSG coverage.
As a reminder to the casual reader, open and laparoscopic Roux-en-Y gastric bypass (RYGBP); laparoscopic adjustable gastric banding (LAGB); and open and laparoscopic biliopancreatic diversion with duodenal switch (BPD/DS) are only covered by Medicare when performed at facilities that are: (1) certified by the American College of Surgeons as a Level 1 Bariatric Surgery Center (program standards and requirements in effect on February 15, 2006); or (2) certified by the American Society for Bariatric Surgery as a Bariatric Surgery Center of Excellence (program standards and requirements in effect on February 15,
2006). The program standards include data collection. The American College of Surgeons developed a bariatric database titled Bariatric Surgery Center Network (BSCN) database. The American Society for Bariatric Surgery developed a bariatric database name Bariatric Outcomes Longitudinal Database (BOLD).
We appreciate the premise of the commenters, but to date the materials produced pursuant to those initiatives have characteristics that limit their persuasiveness. While the data included in the public comment was helpful, to our knowledge it has not been published in a peer review journal. We prefer in
order to maximize public transparency that CMS’ evidentiary review relies on analysis of mature complete data sets that have been published in peer-review journals. We do not believe this is the case with the bariatric surgery databases referenced by the commenter.
We are not aware of published LSG studies using BOLD data.
CMS reviewed the 2011 Hutter et al study published that used American College of Surgeons—Bariatric Surgery Center Network (BSCN) accreditation program, and its prospective, longitudinal, data collection system based on standardized definitions and collected by trained data reviewers. The article is titled, The First Report from the American College of Surgeons Bariatric Surgery Center Network: Laparoscopic
Sleeve Gastrectomy has Morbidity and Effectiveness Positioned Between the Band and the Bypass. Of the 28,616 patients evaluated, 944 had the sleeve gastrectomy. The mean age was 46.5. No data specific to Medicare population or people over 65 was included in this article. The follow up was one year only. The author acknowledged the need for longer term outcomes and stated,“as obesity is a lifelong disease, longer term comparative effectiveness of these procedures at 5 years, 10 years and beyond, are most critical, and are yet to be determined.
Several commenters affected by obesity offered stories of their personal struggles.
While we acknowledge that some individuals are sincerely conveying their personal experiences with obesity and bariatric surgery, we must point out that evidence from formal clinical studies is more persuasive to draw confident conclusions about the impact of medical technologies.
VIII. CMS Analysis
National coverage determinations (NCDs) are determinations by the Secretary with respect to whether or not a particular item or service is covered nationally by Medicare (§1862(l) of the Act).
In order to be covered by Medicare, an item or service must fall within one or more benefit categories
contained within Part A or Part B, and must not be otherwise excluded from coverage. Moreover, section 1862(a)(1) of the Social Security Act in part states, with limited exceptions, no payment may be made under part A or part B for any expenses incurred for items or services:
- Which, are not reasonable and necessary for the diagnosis or treatment of illness or injury or to improve the functioning of a malformed body member (§1862(a)(1)(A)), or
- In the case of research conducted pursuant to section 1142, which is not reasonable and necessary to carry out the purposes of that section. ((§1862(a)(1)(E)).
Section 1142 of the Social Security Act describes the authority of the AHRQ. Under section 1142, research may be conducted and supported on the outcomes, effectiveness, and appropriateness of health care services and procedures to identify the manner in which diseases, disorders, and other health conditions can be prevented, diagnosed, treated, and managed clinically.
Section 1862(a)(1)(E) allows Medicare to cover under coverage with evidence development (CED) certain items or services for which the evidence is not adequate to support coverage under section 1862(a)(1)(A) and where additional data gathered in the context of a clinical setting would further clarify the impact of these items and services on the health of Medicare beneficiaries. For your convenience, the 2006 CED guidance document is available at http://www.cms.gov/determinationprocess/downloads/ced.pdf
As noted earlier, our review sought the answer to the question below. We have repeated it here for the convenience of the reader.
- Is the evidence sufficient to determine that laparoscopic sleeve gastrectomy improves health outcomes for Medicare beneficiaries who have a BMI ≥ 35 kg/m2, have at least one co-morbidity of obesity and have been previously unsuccessful with medical treatment?
Obesity is a risk factor for cardiovascular disorders and arthritis related conditions. However, many individuals who have a BMI ≥ 35 kg/m2 are asymptomatic and may be relatively healthy when the decision for surgery is considered. Consideration of long term benefits and harms must be carefully
weighed to ensure that there is a clinically meaningful benefit, as bariatric surgery does historically have significant associated morbidity risks and even mortality. In Medicare population, who generally have comorbidities, there are additional concerns. Flum and colleagues (2005) noted that “patients aged 65 years or older had a substantially higher risk of death within the early postoperative period than younger patients.” Evidence beyond a short timeframe would be helpful to demonstrate benefit given the initial postoperative risk and the permanent, irreversible nature of the surgery.
Initially sleeve gastrectomy was performed as “the gastric component of the ASMBS-approved bariatric procedure of biliopancreatic diversion with duodenal switch and began its evolution as a primary operation with the observation that a single-stage laparoscopic duodenal switch in super obese patients with major
co-morbidities demonstrated a high risk of complications and mortality” (ASMBS, 2010). In this situation, sleeve gastrectomy was considered “a risk reduction strategy for high-risk patients” (ASMBS, 2010). We do not believe evidence in this context is applicable to our analysis of LSG as a definitive, stand-alone bariatric procedure for obesity. For our analysis, high quality evidence specifically on stand-alone LSG is needed to determine if it improves health outcomes in the population of interest. This historical occurrence does point out that this gastric restrictive procedure was initially done for short term weight loss, as a precursor to perhaps a more effective, permanent strategy of malabsorption. Without comparative data we do not know the effect of either procedure alone.
We did not find any RCTs that compared LSG to medical management or another bariatric surgery approach that focused on adults who were ≥65 years old. Three bariatric surgery registry analyses (Birkmeyer, 2010, DeMaria, 2010 and Hutter, 2011) were published and included adults who were ≥65 years of age; however, results were not presented separately in these analyses. Thus, a review of these publications could not establish the risk/benefit profile of LSG for older patients.
Since the evidence specifically for older adults is very limited and we have younger beneficiaries who may be putative candidates for LSG, we considered evidence on health outcomes in younger populations. This is also relevant since about 16% of Medicare beneficiaries are under the age of 65 and qualify based on disability. However, generalizability from a young, non-disabled population to a disabled population is difficult to establish broadly and may depend on consideration of individual patient factors.
There were three published RCTs (Himpens, 2006; Karamanakos, 2008; Schauer, 2012) which evaluated weight loss as a primary outcome or secondary outcome but no published RCT evaluated mortality. Mortality either from comorbidities or as a complication from surgery is an important consideration.
The RCT by Himpens reported three-year outcomes while the RCTs by Karamankos reported 1-year results. Since the publication of the proposed decision, an additional RCT (Schauer, 2012) was published and enhanced the evidence base for younger adults with complicated obesity, though the results were only reported for 1
year. We had noted that the two earlier RCTs did not necessarily represent the LSG procedure currently performed in the U.S. and multiple component approach to obesity. The recent trial by Schauer et al. included an intensive medical therapy group and thus helped address these evidentiary concerns.
Schauer et al. had a primary outcome of glycated hemoglobin level (a biomarker) and would not have met our review inclusion criteria if weight change were not a reported secondary outcome. In the absence of mortality data, long term weight loss is a more persuasive outcome since the obvious intent of the bariatric surgery is reduction of weight to produce improvements in chronic co-morbidities. These investigators also plan to report 4 year follow-up results which will be extremely important to assess longer term benefits and harms. While long term outcomes on the benefits and harms of LSG have not yet been reported from the clinical trials, some data on adverse events are available from the large registries, but the data may not have been systematically collected. The reports so far do not suggest any significant differences between LSG and other forms of bariatric surgery, but we do know that not all bariatric surgeries target the same areas of the digestive system. Additionally, we do not know the effect on outcomes and adverse events in general of different surgical techniques, which also complicates current data interpretation.
As Flum noted, age is an important factor in adverse outcomes from bariatric surgery. DeMaria
noted that the “role of bariatric procedures in patients outside the commonly defined age range (18 to 60 years) is not well established”, but also reported that a number of other factors have been found “to contribute to increased mortality include lack of experience on the part of the surgeon or the program,
advanced patient age, male sex, severe obesity (BMI ≥ 50), and coexisting conditions.” While recent trials have focused on patients 60 years and younger, the Medicare population for younger adults is quite variable in terms of co-morbidities and disabilities as mentioned earlier. The younger Medicare population’s unique characteristics such as disability make applying the study findings on younger study participants less precise. Since no study stratified participants by payor or disability, conclusions based on younger, apparently non-disabled study participants without ESRD cannot be confidently applied broadly to younger, disabled Medicare beneficiaries. While some selected younger disabled Medicare beneficiaries may benefit from LSG, no generalized conclusions can be made for all younger Medicare beneficiaries.
Although CMS proposed CED and we continue to believe that methodologically rigorous clinical trials would address important questions, we also understand that LSG is not commonly considered for older patients, which is reflected in the lack of older subjects in the reported clinical studies. New evidence could support the broader identification of patients who would be more likely to benefit from LSG and might permit us to make a more general positive national coverage determination in the future. New evidence on the long
term benefit of LSG would assist patients and their treating physicians who make choices from the available bariatric surgery options.
Beyond the three clinical criteria described in our proposed decision: a body-mass index (BMI) ≥ 35 kg/m2, at least one co-morbidity related to obesity, and previously lack of success with medical
treatment for obesity, we are not able at this time to identify broadly applicable clinical predictors of successful LSG. While LSG may be promising for some individuals with obesity, the underlying disease conditions leading to their Medicare eligibility may speak to pertinent clinical factors that would make
LSG more or less appropriate management.
Other Medicare covered bariatric surgeries are furnished in facilities that meet certain certification requirements established. We expect that LSG would more likely be furnished as an additional option in facilities that already have established bariatric programs, rather than in any newly developed LSG-only program.
In summary, we believe coverage of stand-alone LSG in patients with the three clinical criteria described above should be determined by our local administrative contractors, who are in a better position to consider characteristics of individual beneficiaries and the performance of bariatric surgery facilities within their jurisdictions.
Obesity is increasing in older adults in general. “The prevalence of overweight and obesity is increasing among older age groups in developed countries, in both sexes, all ages, all races, all educational levels, both smokers and nonsmokers; an increase in BMI has been observed even among people with the highest levels of BMI” (Zamboni et al., 2005). In the general population, the United States Preventive Services Task Force (USPSTF) noted that “obesity is especially common in African Americans, some Hispanic populations, and Native Americans and some health sequelae reflect similar ethnic differences.” Hutter and colleagues (2011) reported that white patients comprised 67.48% of patients who underwent LSG.
The available evidence does not clearly and broadly distinguish the patients who will experience an improved outcome from those who will derive harm such as postoperative complications or adverse effects from LSG. However, taking into consideration the seriousness of obesity, the possibility of benefit in highly selected patients in qualified centers, we believe that local Medicare contractor determination on a
case-by-case basis balances these considerations in the interests of our beneficiaries. Our local contractors are in a better position to consider characteristics of individual beneficiaries and the performance of eligible bariatric centers within their jurisdictions. Therefore, Medicare Administrative Contractors acting within their respective jurisdictions will make an initial determination of coverage under section 1862(a)(1)(A) and we are not making a national coverage determination under section 1869(F).
Medicare Administrative Contractors acting within their respective jurisdictions may determine coverage of stand-alone laparoscopic sleeve gastrectomy (LSG) for the treatment of co-morbid conditions related to obesity in Medicare beneficiaries only when all of the following conditions A-C are satisfied.
- The beneficiary has a body-mass index (BMI) ≥ 35 kg/m2,
- The beneficiary has at least one co-morbidity related to obesity, and
- The beneficiary has been previously unsuccessful with medical treatment for obesity.
Appendix A: General Methodological Principles of Study Design
General Methodological Principles of Study Design
(Section VI of the Proposed Decision Memorandum)
General Methodological Principles of Study Design
When making national coverage determinations, CMS evaluates relevant clinical evidence to determine whether or not the evidence is of sufficient quality to support a finding that an item or service is reasonable and necessary. The overall objective for the critical appraisal of the evidence is to determine to what degree we are confident that: 1) the specific assessment questions can be answered conclusively; and 2) the intervention will improve health outcomes for patients.
We divide the assessment of clinical evidence into three stages: 1) the quality of the individual studies; 2) the generalizability of findings from individual studies to the Medicare population; and 3) overarching conclusions that can be drawn from the body of the evidence on the direction and magnitude of the intervention’s potential risks and benefits.
The methodological principles described below represent a broad discussion of the issues we consider when reviewing clinical evidence. However, it should be noted that each coverage determination has its unique methodological aspects.
Assessing Individual Studies
Methodologists have developed criteria to determine weaknesses and strengths of clinical research. Strength of evidence generally refers to: 1) the scientific validity underlying study findings regarding causal relationships between health care interventions and health outcomes; and 2) the reduction of bias. In general, some of the methodological attributes associated with stronger evidence include those listed below:
- Use of randomization (allocation of patients to either intervention or control group) in order to minimize bias.
- Use of contemporaneous control groups (rather than historical controls) in order to ensure comparability between the intervention and control groups.
- Prospective (rather than retrospective) studies to ensure a more thorough and systematical assessment of factors related to outcomes.
- Larger sample sizes in studies to demonstrate both statistically significant as well as clinically significant outcomes that can be extrapolated to the Medicare population. Sample size should be large enough to make chance an unlikely explanation for what was found.
- Masking (blinding) to ensure patients and investigators do not know to which group patients were assigned (intervention or control). This is important especially in subjective outcomes, such as pain or quality of life, where enthusiasm and psychological factors may lead to an improved perceived outcome by either the patient or assessor.
Regardless of whether the design of a study is a randomized controlled trial, a non-randomized controlled trial, a cohort study or a case-control study, the primary criterion for methodological strength or quality is the extent to which differences between intervention and control groups can be attributed to the intervention studied. This is known as internal validity. Various types of bias can undermine internal validity. These include:
- Different characteristics between patients participating and those theoretically eligible for study but not participating (selection bias).
- Co-interventions or provision of care apart from the intervention under evaluation (performance bias).
- Differential assessment of outcome (detection bias).
- Occurrence and reporting of patients who do not complete the study (attrition bias).
In principle, rankings of research design have been based on the ability of each study design category to minimize these biases. A randomized controlled trial minimizes systematic bias (in theory) by selecting a sample of participants from a particular population and allocating them randomly to the intervention and control groups. Thus, in general, randomized controlled studies have been typically assigned the greatest strength, followed by non-randomized clinical trials and controlled observational studies. The design, conduct and analysis of trials are important factors as well. For example, a well designed and conducted observational study with a large sample size may provide stronger evidence than a poorly designed and conducted randomized controlled trial with a small sample size. The following is a representative list of study designs (some of which have alternative names) ranked from most to least methodologically rigorous in their potential ability to minimize systematic bias:
- Randomized controlled trials
- Non-randomized controlled trials
- Prospective cohort studies
- Retrospective case control studies
- Cross-sectional studies
- Surveillance studies (e.g., using registries or surveys)
- Consecutive case series
- Single case reports
When there are merely associations but not causal relationships between a study’s variables and outcomes, it is important not to draw causal inferences. Confounding refers to independent variables that systematically vary with the causal variable. This distorts measurement of the outcome of interest because its effect size is mixed with the effects of other extraneous factors. For observational, and in some cases randomized controlled trials, the method in which confounding factors are handled (either through stratification or appropriate statistical modeling) are of particular concern. For example, in order to interpret and generalize conclusions to our population of Medicare patients, it may be necessary for studies to match or stratify their intervention and control groups by patient age or co-morbidities.
Methodological strength is, therefore, a multidimensional concept that relates to the design, implementation and analysis of a clinical study. In addition, thorough documentation of the conduct of the research, particularly study selection criteria, rate of attrition and process for data collection, is essential for CMS to adequately assess and consider the evidence.
Generalizability of Clinical Evidence to the Medicare Population
The applicability of the results of a study to other populations, settings, treatment regimens and outcomes assessed is known as external validity. Even well-designed and well-conducted trials may not supply the evidence needed if the results of a study are not applicable to the Medicare population. Evidence that provides accurate information about a population or setting not well represented in the Medicare program would be considered but would suffer from limited generalizability.
The extent to which the results of a trial are applicable to other circumstances is often a matter of judgment that depends on specific study characteristics, primarily the patient population studied (age, sex, severity of disease and presence of co-morbidities) and the care setting (primary to tertiary level of care, as well as the experience and specialization of the care provider). Additional relevant variables are treatment regimens (dosage, timing and route of administration), co-interventions or concomitant therapies,
and type of outcome and length of follow-up.
The level of care and the experience of the providers in the study are other crucial elements in assessing a study’s external validity. Trial participants in an academic medical center may receive more or different attention than is typically available in non-tertiary settings. For example, an investigator’s lengthy and detailed explanations of the potential benefits of the intervention and/or the use of new equipment provided to the academic center by the study sponsor may raise doubts about the applicability of study findings to community practice.
Given the evidence available in the research literature, some degree of generalization about an intervention’s potential benefits and harms is invariably required in making coverage determinations for the Medicare population. Conditions that assist us in making reasonable generalizations are biologic plausibility, similarities between the populations studied and Medicare patients (age, sex, ethnicity and clinical presentation) and similarities of the intervention studied to those that would be routinely available in community practice.
A study’s selected outcomes are an important consideration in generalizing available clinical evidence to Medicare coverage determinations. One of the goals of our determination process is to assess health outcomes. These outcomes include resultant risks and benefits such as increased or decreased morbidity and mortality. In order to make this determination, it is often necessary to evaluate whether the strength of the evidence is adequate to draw conclusions about the direction and magnitude of each individual outcome relevant to the intervention under study. In addition, it is important that an intervention’s benefits are clinically significant and durable, rather than marginal or short-lived. Generally, an intervention is not
reasonable and necessary if its risks outweigh its benefits.
If key health outcomes have not been studied or the direction of clinical effect is inconclusive, we may also evaluate the strength and adequacy of indirect evidence linking intermediate or surrogate outcomes to
our outcomes of interest.
Assessing the Relative Magnitude of Risks and Benefits
Generally, an intervention is not reasonable and necessary if its risks outweigh its benefits. Health outcomes are one of several considerations in determining whether an item or service is reasonable and necessary. CMS places greater emphasis on health outcomes actually experienced by patients, such as quality of life, functional status, duration of disability, morbidity and mortality, and less emphasis on outcomes that patients do not directly experience, such as intermediate outcomes, surrogate outcomes, and laboratory or radiographic responses. The direction, magnitude, and consistency of the risks and benefits across studies are also important considerations. Based on the analysis of the strength of the evidence, CMS
assesses the relative magnitude of an intervention or technology’s benefits and risk of harm to Medicare beneficiaries.
Appendix B – Excluded Studies
Behrens C, Tang BQ, Amson BJ. Early results of a Canadian laparoscopic sleeve gastrectomy experience. Can J Surg 2011;54:138-43.
Bohdjalian A, Langer FB, Shakeri-Leidenmühler S, Gfrerer L, Ludvik B, Zacherl J, Prager G. Sleeve gastrectomy as sole and definitive bariatric procedure: 5-year results for weight loss and ghrelin. Obes Surg 2010;20:535-40. Epub 2010 Jan 22.
Chopra A, Chao E, Etkin Y, Merklinger L, Lieb J. Delany H. Laparoscopic sleeve gastrectomy for obesity: can it be considered a definitive procedure? Surg Endosc 2011 Dec 17. [Epub ahead of print]
D'Hondt M, Vanneste S, Pottel H, Devriendt D, Van Rooy F, Vansteenkiste F. Laparoscopic sleeve gastrectomy as a single-stage procedure for the treatment of morbid obesity and the resulting quality of life, resolution of comorbidities, food tolerance, and 6-year weight loss. Surg Endosc 2011;25:2498-504.
Himpens J, Dobbeleir J, Peeters G. Long-term results of laparoscopic sleeve gastrectomy for obesity. Ann Surg 2010;252:319-24.
Johnston D, Dachtler J, Sue-Ling HM, King RF, Martin G. The Magenstrasse and Mill operation for morbid obesity. Obes Surg 2003;13:10-6.
Leivonen MK, Juuti A, Jaser N, Mustonen H. Laparoscopic sleeve gastrectomy in patients over 59 years: early recovery and 12-month follow-up. Obes Surg 2011;21:1180-7.
Nath A, Leblanc KA, Hausmann MG, Kleinpeter K, Allain BW. Romero R. Laparoscopic sleeve gastrectomy: our first 100 patients. JSLS 2010;14:502-8. doi: 10.4293/108680810X12924466007809.
Sabbagh C, Verhaeghe P, Dhahri A, Brehant O, Fuksa D, Badaoui R, Regimbeau JM. Two-year results on morbidity, weight loss and quality of life of sleeve gastrectomy as first procedure, sleeve gastrectomy after failure of gastric banding and gastric banding. Obes Surg 2010;20:679-84.
Sarela AI, Dexter SP, O'Kane M, Menon A, McMahon MJ. Long-term follow-up after laparoscopic sleeve gastrectomy: 8-9-year results. Surg Obes Relat Dis. 2011 Jul 20. [Epub ahead of print]
Strain GW, Saif T, Gagner M, Rossidis M, Dakin G, Pomp A. Cross-sectional review of effects of laparoscopic sleeve gastrectomy at 1, 3, and 5 years. Surg Obes Relat Dis 2011;7:714-9.
Weiner RA, Weiner S, Pomhoff I, Jacobi C, Makarewicz W, Weigand G. Laparoscopic sleeve gastrectomy—influence of sleeve size and resected gastric volume. Obes Surg 2007;17:1297-305.
Zacharoulis D, Sioka E, Papamargaritis D, Lazoura O, Rountas C, Zachari E, Tzovaras G. Influence of the Learning Curve on Safety and Efficiency of Laparoscopic Sleeve Gastrectomy. Obes Surg 2011 May 12. [Epub
ahead of print]
Appendix C – References Submitted by Public Commenters
Aarts EO, Janssen IM, Berends FJ. The gastric sleeve: losing weight as fast as micronutrients? Obes Surg. 2011 Feb;21(2):207-11.
Abbatini F, Capoccia D, Casella G, Coccia F, Leonetti F, Basso N. Type 2 diabetes in obese patients with body mass index of 30-35 kg/m2: sleeve gastrectomy versus medical treatment. Surg Obes Relat Dis. 2012
Jan-Feb;8(1):20-4. Epub 2011 Jul 13.
Bayham BE, Greenway FL, Bellanger DE, O'Neil CE. Early resolution of type 2 diabetes seen after Roux-en-Y gastric bypass and vertical sleeve gastrectomy. Diabetes Technol Ther. 2012 Jan;14(1):30-4. Epub 2011 Sep
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. Obes Surg. 2010 Apr;20(4):447-53. Epub 2010 Jan 26.
Himpens J, Dobbeleir J, Peeters G. Long-term results of laparoscopic sleeve gastrectomy for obesity. Ann Surg. 2010 Aug;252(2):319-24.
Leonetti F, Capoccia D, Coccia F, Casella G, Baglio G, Paradiso F, Abbatini F, Iossa A, Soricelli E, Basso N. Obesity, Type 2 Diabetes Mellitus, and Other Comorbidities: A Prospective Cohort Study of Laparoscopic Sleeve Gastrectomy vs Medical Treatment. Arch Surg. 2012 Apr 16.
Leyba JL, Aulestia SN, Llopis SN. Laparoscopic Roux-en-Y gastric bypass versus laparoscopic sleeve gastrectomy for the treatment of morbid obesity. A prospective study of 117 patients. Obes Surg. 2011
Kashyap SR, Bhatt DL, Schauer PR; STAMPEDE Investigators. Bariatric surgery vs. advanced practice medical management in the treatment of type 2 diabetes mellitus: rationale and design of the Surgical Therapy And
Medications Potentially Eradicate Diabetes Efficiently trial (STAMPEDE). Diabetes Obes Metab. 2010 May;12(5):452-4.
Mingrone G, Panunzi S, De Gaetano A, Guidone C, Iaconelli A, Leccesi L, Nanni G, Pomp A, Castagneto M, Ghirlanda G, Rubino F. Bariatric surgery versus conventional medical therapy for type 2 diabetes. N Engl J Med. 2012 Apr 26;366(17):1577-85. Epub 2012 Mar 26.
Nienhuijs SW, de Zoete JP, Berende CA, de Hingh IH, Smulders JF. Evaluation of laparoscopic sleeve gastrectomy on weight loss and co-morbidity. Int J Surg. 2010;8(4):302-4. Epub 2010 Mar 19.
Nocca D, Guillaume F, Noel P, Picot MC, Aggarwal R, El Kamel M, Schaub R, de Seguin de Hons C, Renard E, Fabre JM. Impact of laparoscopic sleeve gastrectomy and laparoscopic gastric bypass on HbA1c blood level and
pharmacological treatment of type 2 diabetes mellitus in severe or morbidly obese patients. Results of a multicenter prospective study at 1 year. Obes Surg. 2011 Jun;21(6):738-43.
O'Keefe KL, Kemmeter PR, Kemmeter KD. Bariatric surgery outcomes in patients aged 65 years and older at an American Society for Metabolic and Bariatric Surgery Center of Excellence. Obes Surg. 2010 Sep;20(9):1199-205.
Saif T, Strain GW, Dakin G, Gagner M, Costa R, Pomp A. Evaluation of nutrient status after laparoscopic sleeve gastrectomy 1, 3, and 5 years after surgery. Surg Obes Relat Dis. 2012 Feb 1.
Sarela AI, Dexter SP, O'Kane M, Menon A, McMahon MJ. Long-term follow-up after laparoscopic sleeve gastrectomy: 8-9-year results. Surg Obes Relat Dis. 2011 Jul 20.
Schauer PR, Kashyap SR, Wolski K, Brethauer SA, Kirwan JP, Pothier CE, Thomas S, Abood B, Nissen SE, Bhatt DL. Bariatric surgery versus intensive medical therapy in obese patients with diabetes. N Engl J Med 2012 Apr 26;366(17):1567-76.
Schlienger JL, Pradignac A, Luca F, Meyer L, Rohr S. Medical management of diabetes after bariatric surgery. Diabetes Metab. 2009 Dec;35(6 Pt 2):558-61.
Stroh C, Birk D, Flade-Kuthe R, Frenken M, Herbig B, Höhne S, Köhler H, Lange V, Ludwig K, Matkowitz R, Meyer G, Pick P, Horbach T, Krause S, Schäfer L, Schlensak M, Shang E, Sonnenberg T, Susewind M, Voigt H, Weiner R, Wolff S, Wolf AM, Schmidt U, Lippert H, Manger T; Bariatric Surgery Working Group. Results of sleeve gastrectomy-data from a nationwide survey on bariatric surgery in Germany. Obes Surg. 2009 May;19(5):632-40. Epub 2009 Jan 29.