Bariatric Surgery for the Treatment of Morbid Obesity - Facility Certification Requirement

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The Centers for Medicare & Medicaid Services (CMS) has determined that the evidence is sufficient to conclude that continuing the requirement for certification for bariatric surgery facilities would not improve health outcomes for Medicare beneficiaries. Therefore, CMS has decided to remove this certification requirement. CMS also decided that no changes be made to the bariatric surgery procedures that are deemed covered in section 100.1 of the National Coverage Determination (NCD) Manual. The evidence continues to support that 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) continue to be reasonable and necessary for Medicare beneficiaries who have a body-mass index (BMI) ≥ 35, have at least one co-morbidity related to obesity, and have been previously unsuccessful with medical treatment for obesity. Lastly, we decided to change the title to better reflect the scope of the NCD and to make it clear in the manual that under the existing policy the local Medicare Administrative Contractors have the authority to make coverage decisions for certain patients for any bariatric surgery procedures not specifically identified as covered or non-covered by an NCD. In addition, to the decision above, CMS is renumbering and consolidating its manual for section 100.1. This is an administrative change only to make it easier for the public to read and understand the NCD manual. There is no change in coverage because of the renumbering and consolidation. The additional NCDs related to bariatric surgery will be consolidated and subsumed into section 100.1 of the NCD Manual. These include sections 40.5, 100.8, 100.11 and 100.14. The changes to the manual are reflected in attachment Appendix C.

Decision Memo: To: Administrative File: CAG-00250R3 From: 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 Lori Paserchia, MD Lead Medical Officer Deirdre O’Connor Lead Health Policy Analyst Subject: Decision Memorandum for CAG #00250R3 Reconsideration of Facility Certification Requirement for Coverage of Covered Bariatric Surgery Procedures Date: September 24, 2013 I. Decision The Centers for Medicare & Medicaid Services (CMS) has determined that the evidence is sufficient to conclude that continuing the requirement for certification for bariatric surgery facilities would not improve health outcomes for Medicare beneficiaries. Therefore, CMS has decided to remove this certification requirement. CMS also decided that no changes be made to the bariatric surgery procedures that are deemed covered in section 100.1 of the National Coverage Determination (NCD) Manual. The evidence continues to support that 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) continue to be reasonable and necessary for Medicare beneficiaries who have a body-mass index (BMI) ≥ 35, have at least one co-morbidity related to obesity, and have been previously unsuccessful with medical treatment for obesity. Lastly, we decided to change the title to better reflect the scope of the NCD and to make it clear in the manual that under the existing policy the local Medicare Administrative Contractors have the authority to make coverage decisions for certain patients for any bariatric surgery procedures not specifically identified as covered or non-covered by an NCD. In addition, to the decision above, CMS is renumbering and consolidating its manual for section 100.1. This is an administrative change only to make it easier for the public to read and understand the NCD manual. There is no change in coverage because of the renumbering and consolidation. The additional NCDs related to bariatric surgery will be consolidated and subsumed into section 100.1 of the NCD Manual. These include sections 40.5, 100.8, 100.11 and 100.14. The changes to the manual are reflected in attachment Appendix C. II. Background The following acronyms are used throughout this document. For the readers convenience they are listed here in alphabetical order. ACS - American College of Surgeons AHRQ - Agency for Healthcare Research and Quality ASMBS - American Society for Metabolic and Bariatric Surgery BMI - body-mass index BSCOE - Bariatric Surgery Center of Excellence CE - composite event CI – confidence interval COE - center of excellence CVA- cerebrovascular accident DD – difference-in-difference DGR - diagnosis-related group DVT - deep vein thrombosis LABS - Longitudinal Assessment of Bariatric Surgery LAGB - laparoscopic adjustable gastric banding LRYGB - laparoscopic Roux-en-Y gastric bypass MBSAQIP - Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program MBSC – Michigan Bariatric Surgery Collaborative NCA - National Coverage Analysis NCD - National Coverage Determination NIDDK - National Institute of Diabetes, Digestive and Kidney Diseases NIH - National Institutes of Health OR - odds ratio ORYGB - open Roux-en-Y gastric bypass ResDAC - Research Data Assistance Center RR – relative risk RYGB - Roux-en-Y gastric bypass SD -standard deviation SG - sleeve gastrectomy SRC - Surgical Review Corporation TAVR - Transcatheter Aortic Valve Replacement UHC - University HealthSystem Consortium The scope of this national coverage analysis (NCA) includes a review of the evidence on whether the facility certification requirement continues to improve outcomes for covered bariatric surgery procedures in the Medicare population. CMS also plans to make a number of administrative changes to the NCD. These administrative changes are further explained in section III.A of this document. We believe these administrative changes will make referencing the NCD on bariatric surgery easier for the public. In February 2006, CMS completed a reconsideration of a national coverage determination (NCD) for bariatric surgery and published a final decision memorandum, which is available at http://www.cms.gov/medicare-coverage-database/details/nca-decision-memo.aspx?NCAId=160 . The requestors for that 2006 reconsideration had asked that Medicare cover numerous bariatric surgical procedures. CMS performed a review of the available evidence at that time and ultimately concluded that the evidence supported coverage for certain procedures and not for others. However, the coverage decision also specified, “CMS has determined that covered bariatric surgery procedures are reasonable and necessary only when performed at facilities that are: (1) certified by the American College of Surgeons (ACS) 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 (BSCOE) (program standards and requirements in effect on February 15, 2006) (CMS Bariatric Surgery 2006).” In the review and analysis of the evidence at that time, CMS identified several facility and physician criteria that were believed to be essential for optimizing outcomes for bariatric surgery. These criteria focused on the competency of surgeons, training and experience that met national standards and training and experience in managing morbidly obese patients prior to, during and following surgery. There was a rapid increase in the rate of bariatric surgery procedures at that time, resulting in a need to establish practice standards (Livingston 2004). We found that both the ACS and the American Society for Bariatric Surgery (currently the American Society for Metabolic and Bariatric Surgery (ASMBS)) had existing certification programs in place that met or exceeded the criteria outlined in the decision memorandum of 2006. The facility certification requirement that CMS established in the 2006 decision was supported by the evidence at that time of rapid growth of bariatric surgery programs, improved outcomes in the older Medicare population at higher volume facilities and with higher volume surgeons (Flum 2005) and by consensus opinion for the need for facility standards from the professional societies and other physicians in comments submitted in response to the proposed decision memorandum for bariatric surgery (CMS Bariatric Surgery 2006). Commenters supported the certification requirement, including a volume requirement, as documented in supporting comments provided through the public comment process on the proposed decision memorandum (CMS Bariatric Surgery 2006). CMS has now been asked to reevaluate this facility certification requirement. While CMS established a requirement for facility certification, often this is referred to as a center of excellence (COE) program. III. History of Medicare Coverage In 2006, CMS established a National Coverage Determination (NCD) on Bariatric Surgery for the Treatment of Morbid Obesity (NCD Manual Section 100.1 http://www.cms.gov/Regulations-and-Guidance/Guidance/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 these bariatric procedures are 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 co-morbidity. In June 2012, CMS reconsidered the NCD specifically regarding the laparoscopic sleeve gastrectomy (LSG) procedure and determined 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/m 2 , The beneficiary has at least one co-morbidity related to obesity, and The beneficiary has been previously unsuccessful with medical treatment for obesity. A. Current Reconsideration CMS received a formal request from Dr. John Birkmeyer, Dr. Nancy Birkmeyer and Dr. Justin Dimick asking for a reconsideration of the NCD on bariatric surgery, specifically requesting that CMS abandon the requirement for facility certification/COE designation. CMS opened this national coverage analysis (NCA) to review the evidence on whether certification of bariatric surgery facilities improves outcomes in Medicare beneficiaries who undergo a currently covered bariatric surgery procedure. At this time, we also plan to make a number of changes to section 100.1 of the NCD Manual. These changes include changing the title to clearly reflect the scope of the bariatric surgery NCD and adding a statement to make it clear in the manual that under the existing policy the local Medicare Administrative Contractors have the authority to make coverage decisions for any bariatric surgery procedures not specifically identified as covered or non-covered by an NCD. In addition, we plan at this time to consolidate all of the bariatric surgery NCDs by subsuming related sections 40.5, 100.8, 100.11 and 100.14 into section 100.1. This is an administrative change and there is no change in the coverage due to the consolidation. We believe this administrative change will make it easier for the public to access our policy on bariatric surgery. 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. Note: This may not be an exhaustive list of all applicable Medicare benefit categories for this item or service. IV. Timeline of Recent Activities Date Action 01/24/2013 CMS initiates this national coverage analysis. Initial public comment period opens. 02/23/2013 Initial public comment period closes. 03/05/2013 Telephone conference with leadership of ASMBS. 06/27/2013 Proposed decision memorandum posted. 07/27/2013 Second comment period closes. 08/15/2013 Telephone conference with leadership of ASMBS. V. Food and Drug Administration (FDA) Status Various devices used in a bariatric surgery may fall under FDA regulatory oversight. However, our review is focused on the evidence for the CMS requirement for certification rather than FDA approval or clearance of a specific device. We continue to expect that those covered bariatric surgeries that include a device will only use devices that have been approved or cleared by FDA. 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. VII. Evidence A. Introduction In this NCD reconsideration, we reviewed evidence generated since we established the facility certification requirement in 2006. In reviewing the evidence, we focused on reports of analyses that compared outcomes in facilities that met those standards compared to facilities that did not meet those standards. We are concerned with short-term as well as long-term mortality and morbidity outcome rates in Medicare beneficiaries. B. Literature Search CMS performed its most recent literature search using PubMed on August 22, 2013 with the search terms “bariatric” and “center of excellence.” The following limitations were applied: Humans, Clinical Trial, English and Publication Date from 01/01/2006 to 08/22/2013. C. Discussion of Evidence Reviewed 1. Question: The question of interest for this NCA is: Is the evidence sufficient to conclude that facility certification (sometimes referred to as a COE designation) improves meaningful health outcomes for Medicare beneficiaries who undergo a covered bariatric surgery? 2. External technology assessment (TA) An external TA was not commissioned. 3. Internal technology assessment Three articles (Livingston 2009; Birkmeyer 2010; Dimick 2013) were submitted by the requester. The CMS literature search identified two of the articles submitted by the requester (Livingston and Birkmeyer) and two additional articles (Kwon 2012 and Kohn 2010). Two articles (Nguyen 2010; Flum 2011) were identified during a search of the bibliographies of other articles and one additional article (Nguyen 2012) was identified by public commenters. One article (Nguyen 2013 cited as Jafari et al. 2013) was submitted after the second public comment period. All nine articles are reviewed below. Livingston EH. Bariatric surgery outcomes at designated centers of excellence vs nondesignated programs. Arch Surg 2009;144:319-325. The author performed an analysis of data from the 2005 National Inpatient Survey, which is a population-representative sampling of hospital discharges obtained from 20% of all hospitalizations in the U.S. each year. The National Inpatient Survey is maintained by the Agency for Healthcare Research and Quality (AHRQ). Bariatric procedures were found by identifying diagnosis related group (DRG) code 288, which is used when the primary reason for hospitalization is for procedures for morbid obesity. The designation of COE was made by visually matching the list of hospitals included in the 2005 National Inpatient Survey and the list of COEs identified on the CMS website. The outcomes of interest were in-hospital mortality and complications; a complication was defined by use of the National Inpatient Survey clinical classification software diagnostic variable 238, which states “complication of surgical procedures or medical care.” Expected mortality was also calculated. Long term outcomes were not evaluated. Logistic regression was performed “to assess the effect of COE status and annual hospital procedure volume on bariatric procedure morbidity and mortality. In-hospital death was the dependent variable, and COE status, annual procedure volume, age and male sex were also entered into the regression equations.” At the time of the analysis, the National Inpatient Survey database listed 253 hospitals; 24 (9.5%) of these were designated as a COE. The CMS website listed 317 COEs during this time hence the analysis included 7.6% of the CMS-identified COEs. A total of 24,783 bariatric procedures were performed in the 253 hospitals included in the analysis; 5420 (28%) of these procedures were performed in a COE. The mean (SD) age was 42.9 (11.2) for the patients treated in a COE and 42.4 (10.7) for the patients treated in a non-COE. Patients greater than 65 years of age comprised 1.3% of patients in the COE group and 1.8% of patients in the non-COE group. Medicare-enrolled patients comprised 8.3% of the COE group and 8.0% of the non-COE group. Information about the BMI or the specific types of bariatric procedures performed was not reported. The author reported that the “mean number of cases performed per facility was substantially greater for COEs than for the hospitals that were not COEs.” The hospital mortality rate was 0.17% in COEs and 0.09% in non-COEs (difference not statistically significant). The complication rate was 6.3% in COEs and 6.4% in non-COEs (difference not statistically significant). After logistic regression modeling it was stated, “Procedure volume was inversely related to complication rates, where as patient age and teaching hospital status were positively associated with postoperative complications.” Upon further regression modeling, the author noted that “As hospital volumes decrease, the expected complication rate increases with profound expansion of the CIs [confidence interval] as the volumes become very low. There are approximately as many hospitals above the 95% CIs as there are below them, suggesting that hospitals may exhibit higher or lower than expected complication rates irrespective of their procedure volume status.” In addition, further analysis of the effect of arbitrarily assigning hospital volume to predefined categories found that “Bariatric procedures conducted at hospitals performing fewer than 125 cases per year would appear to have an 18% greater likelihood of being associated with complications.” The author noted some limitations to his analysis including the fact that the sampling of COEs was only 7.6% of the total number of existing COEs. The author commented, “I found that COEs perform substantially more bariatric procedures than non-COEs, yet both had commensurate outcomes. These findings suggest that the much larger number of hospitals that perform low volumes of bariatric procedures have outcomes similar to the high-volume COEs.” Nguyen NT, Hohmann S, Slone J, Varela E, Smith BR and Hoyt D. Improved bariatric surgery outcomes for Medicare beneficiaries after implementation of the Medicare national coverage determination. Arch Surg 2010;145:72-78. Nguyen and colleagues conducted a retrospective analysis of the University HealthSystem Consortium database, which contains administrative, clinical and financial data. The University HealthSystem Consortium is an alliance of 102 U.S. academic medical centers and approximately 150 affiliated hospitals. Discharge data for “all Medicare and Medicaid patients who underwent open or laparoscopic Roux-en-Y gastric bypass, laparoscopic biliopancreatic diversion with duodenal switch for the treatment of morbid obesity from October 1, 2004 to September 31, 2007” were analyzed as were the data for dual eligible patients. The goal of the analysis was to compare the outcomes and volumes of bariatric procedures performed on Medicare beneficiaries during the 18 months prior to and then during the 18 months after the 2006 NCD issued by CMS. Outcomes assessed were in-hospital mortality, peri-operative complications and observed-to-expected mortality ratio. Long term outcomes were not evaluated. Differences were determined using the Pearson chi-square test. A total of 6264 Medicare and Medicaid patients who met the study criteria underwent bariatric surgery for the treatment of morbid obesity; 3196 patients before the NCD and 3068 patients after NCD implementation. Sixty institutions performed bariatric surgery before NCD implementation and 45 after NCD implementation. The authors noted that “More than half of the patients were between 31 and 50 years of age (51.6% before the NCD and 49.9% after the NCD). There were significantly more individuals greater than 65 years of age within the group after the NCD implementation (7.5% vs 9.6%, P < 0.05).” In addition, the “proportions of patients with diabetes, hypertension, congestive heart failure, liver disease, and chronic pulmonary disease were not significantly different between the 2 groups.” Information regarding the BMI was not reported. Before the NCD, 82.5% of the patients were women while after the NCD 81.5% were women. After implementation of the NCD, “there was a doubling in the volume of laparoscopic gastric banding (231 vs 489 procedures), with a decrease in the volume of gastric bypass (2714 vs 2403 procedures); however, the proportion of laparoscopic gastric bypass procedures increased from 60.0% before the NCD to 77.2% after the NCD.” Regarding outcomes, the authors reported that “Compared with Medicare patients who underwent bariatric surgery before the NCD, patients who underwent bariatric surgery after the NCD had a lower overall complication rate (14.6% vs 10.4%; OR, 1.48; 95% CI, 1.21 – 1.82) and significantly lower rates of postoperative pulmonary complications (2.9% vs 1.7%; OR, 1.76; 95% CI, 1.10 – 2.82), wound infections (1.6% vs 0.7%; OR, 2.16; 95% CI, 1.10 – 4.25), and venous thrombosis or pulmonary embolisms (1.4% vs 0.6%; OR, 2.24; 95% CI, 1.07 – 4.67). No significant difference was seen in in-hospital mortality between groups (0.38% before the NCD vs 0.24% after the NCD). There was a trend toward improvement of the observed-to-expected mortality ratio from 1.07 before to 0.89 after implementation of the NCD.” Of note, the relevant table in the article reported that in-hospital mortality was 0.3% rather than 0.24% as reported in the above quote. In addition the authors stated, “The group before implementation of the NCD had more patients with a higher severity of illness. To eliminate this important confounding variable, we examined the outcomes of bariatric surgery specifically within a subset of patients with major and extreme (higher) severity of illness. Compared with Medicare and Medicaid patients with major or extreme severities of illness who underwent bariatric surgery before the NCD, patients who underwent bariatric surgery after the NCD had a lower overall complication rate (50.1% vs 40.2%; OR, 1.50; 95% CI, 1.09 – 2.07). In addition, because there is an increase in the number of laparoscopic gastric banding procedures after implementation of the NCD, we examined specifically the outcomes of laparoscopic and open gastric bypass procedures performed before and after implementation of the NCD. After implementation of the NCD, Medicare patients (excluding Medicaid patients) who underwent laparoscopic or open gastric bypass benefited from a shorter length of hospital stay and lower overall pulmonary complication rates.” Nguyen et al. addressed several limitations of their study: “The data derived from the UHC only represent in-hospital outcomes without follow-up data. Although data with regard to readmission to the same hospital are identified, any complications or deaths occurring during readmission to a different institution are not captured. The UHC database does not have the patients’ weights or body mass indexes for all patients, and these are important factors in computing risk adjustment of outcomes. In addition, the coding of certain complications may be inaccurate because postoperative adverse events can be subjectively defined and may be coded differently (eg, leaks). However, in-hospital mortality and length of stay are accurate end points because they do not require subjective interpretation. This study is also limited to academic centers, and the results may not be generalizable to nonacademic institutions.” The authors concluded, “the outcomes have improved since the implementation of the Medicare bariatric surgery NCD. Since the implementation of the NCD, the volume of bariatric procedures remained the same, whereas the number of institutions caring for morbidly obese patients decreased from 60 to 45. Concurrently, there was a doubling of laparoscopic gastric banding procedures and an increase in the proportion of laparoscopic gastric bypass procedures from 60.0% to 77.2%. Implementation of the NCD did not impede access to care because the volume of bariatric procedures performed on Medicare beneficiaries returned to baseline volume within 1 year after the NCD implementation and exceeded the baseline volume at 2 years after the NCD implementation.” 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;304:435-442. Birkmeyer et al. performed an analysis of data from the Michigan Bariatric Surgery Collaborative (MBSC) 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 contained data voluntarily submitted from 25 hospitals that performed at least 25 bariatric procedures per year. Data for the registry were collected by medical chart review. All patients undergoing bariatric surgery from June 2006 to September 2009 (n = 15,275) were included. Patients undergoing revisional surgery or duodenal switch procedures were excluded. The primary outcome was occurrence of a serious complication within 30 days of surgery, which was defined as potentially life-threatening or resulting in death or disability. Long term outcomes were not evaluated. The authors selected annual hospital and surgeon volume categories “using a combination of generally accepted volume cut points and empirical derivation based on the distribution of patients, hospitals, and surgeons. Sites were deemed centers of excellence if they were designated as such by the American College of Surgeons or the American Society of Metabolic and Bariatric Surgeons at any point during our study period.” Three categories were selected: Low (mean annual surgeon procedure volume of < 100 or mean annual hospital procedure volume of < 150; Medium (mean annual surgeon procedure volume of 100 - 249 or mean annual hospital procedure volume of 150 - 299); High (mean annual surgeon procedure volume of ≥ 250 or mean annual hospital procedure volume of ≥ 300). Median age was 46 years and there were no reported patients 60 years of age or older. Median BMI was 46 kg/m 2 . Men comprised 21% of the population. There were 854 sleeve gastrectomy (SG) procedures, 5380 laparoscopic adjustable gastric band procedures and 9041 open or laparoscopic gastric bypass procedures. Thirty-three (53%), 22 (36%) and 7 (11%) surgeons were in the low, medium and high volume categories, respectively. Ten (40%), nine (36%) and six (24%) hospitals were in the low, medium and high volume categories, respectively. Six of 10 low-volume hospitals, eight of nine medium-volume hospitals and five of six high-volume hospitals were designated as a COE. The authors reported that “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.” The authors further noted that “Risk of serious complications was inversely associated with average annual bariatric procedure volume (Table 2). For surgeon volume, rates in the low-, medium-, and high-volume categories were 3.8% (95% CI, 3.2% - 4.5%), 2.4% (95% CI, 2.1% - 2.8%), and 1.9% (95% CI, 1.4% - 2.3%), respectively (P for trend = 0.001). For hospital volume, adjusted rates of serious complications were 4.1% (95% CI, 3.0% - 5.1%), 2.7% (95% CI, 2.2%-3.2%), and 2.3% (95% CI, 2.0% - 2.6%) in low-, medium-, and high-volume hospitals, respectively (P for the trend < 0.001). Serious complication rates were about twice as high (4.0%; 95% CI, 2.8% - 5.3%) for low-volume surgeons at low-volume hospitals than for high-volume surgeons at high-volume hospitals (1.9%; 95% CI, 1.4% - 2.3%).” For the COE vs non-COE comparison, the authors found that “Overall, rates of serious complications were similar among patients undergoing surgery at a COE (2.7%; 95% CI, 2.5% - 3.1%) than for patients undergoing surgery at non-COE hospitals (2.0%; 95% CI, 1.5% - 2.4%). After adjustment for patient case and procedure mix, there remained no significant difference in rates of serious complications at COE and non-COE hospitals (adjust odds ratio (OR), 1.27; 95% CI, 0.72 – 2.25); P = 0.41). There also was no significant difference (adjusted OR, 1.34; 95% CI, 0.88 – 2.05; P = 0.18) in rates of serious complications in the COE hospitals compared with the non-COE hospitals within hospital procedure volume categories.” In their discussion, the authors stated that “procedure volume has been shown to be an important predictor of adverse outcomes in bariatric surgery.” They also noted a number of limitations to their study including the fact that “because all but 8 of the 25 hospitals were COE-accredited by the end of the study period, we had suboptimal statistical power for detecting differences in risk between COE and non-COE hospitals.” In addition, the authors acknowledged that their “study finding may not be generalizable outside of the state of Michigan.” The authors concluded that “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 not COE status.” Kohn GP, Galanko JA, Overby DW and Farrell TM. High case volumes and surgical fellowships are associated with improved outcomes for bariatric surgery patients: a justification of current credentialing initiatives for practice and training. J Am Coll Surg 2010;210:909. The authors conducted a retrospective analysis of data from 1998 to 2006 from the Nationwide Inpatient Sample database, which was comprised of 1,045 hospitals in 38 states (approximately a 20% stratified sample of all non-Federal hospitals). The goal of the analysis was to examine the effects of case volume and COE status on outcome. Based on the use of ICD-9-CM codes, the procedure groups included in the analysis were gastroplasty, gastric bypass, malabsorptive and laparoscopic adjustable gastric band. Prior to the posting of the 2006 NCD, a hospital's COE status was determined by searching the ACS and ASMBS/SRC websites. Since only hospitals currently certified could be found on these websites, the authors "assumed that current designation as such was in place throughout the study period." For that part of the database collected after the posting of the NCD, the authors determined a hospital's COE status by searching the CMS website. ICD-9-CM codes were used to determine the presence or absence of perioperative complications. For the purposes of the analysis, the occurrence of death or at least one of 15 distinct diagnosis codes resulted in a classification of "any complication." In-hospital mortality was the other outcome studied. Long term outcomes were not studied. Logistic regression modeling was performed. In this model, case volume was used as a continuous variable rather than as a binary variable (e.g., less than 125 cases versus 125 cases or more). The cohort consisted of 102,069 bariatric procedure cases. Patient characteristics such as age, gender or BMI were not reported. However, the authors determined the Charlson comorbidity index for each inpatient record, which is a way to characterize the degree of comorbidity for the patient (the higher the score, the greater the comorbidity). The mean (SD) Charlson index score steadily increased during this time period; the score was 0.308 (0.574) in 1998 and 0.557 (0.712) in 2006. The number of hospitals with an annual case volume of more than 125 steadily increased from 1 in 1998 to 51 in 2004 but then decreased to 37 in 2005 and 39 in 2006. With regards to outcomes, in an analysis that controlled for the Charlson score and year, the overall in-hospital mortality rate for all bariatric cases steadily decreased; the rate was 0.61% in 1998 and 0.13% in 2006. For perioperative complications, the authors noted that for all bariatric cases "Nearly all analyzed complication categories showed an inverse correlation with case volume, with any complication, death, requirement for postoperative abdominal drainage, acute pulmonary embolism, cardiac complications, splenectomy, acute renal failure, bacterial pneumonia, and acute respiratory failure rates achieving statistically significant improvement." No inverse correlation with increasing case volume was seen for acute DVT, myocardial infarction and acute CVA. In an analysis to determine the association between outcomes and COE designation for all bariatric cases after controlling for year, Charlson score and case volume, there was no statistically significant association between complications and the presence of a COE designation by ACS or by ASMBS except for respiratory failure (where a decrease in the rate of respiratory failure was associated with both the ACS-based and the ASMBS-based COE designations) and for acute DVT (where a decrease in the rate of acute DVT was associated with the ACS-based COE designation). Kohn et al. identified some limitations with their analysis. They sourced their data from an administrative database, which is dependent on the use of medical codes that can be clinically-nonspecific or ambiguous and revised periodically over time. These characteristics can lead to undetected, and therefore unaccounted for, changes in the data that were included in the analysis. In addition, the database comprised only a small (20%) sample of the possible hospitals and U.S. states in the U.S. The authors concluded that "the hypothesized positive volume-outcomes relationship of bariatric surgery has been shown with analysis of case volume as a continuous variable and without arbitrarily categorizing hospitals to case volume groups. The concept of volume-independent COE designation has been supported, although there is minimal association between outcomes and the credentialing process itself." Flum DR, Kwon S, MacLeod K, Wang B, Alfonso-Cristancho R, Garrison LP and Sullivan SD. The use, safety and cost of bariatric surgery before and after Medicare's national coverage decision. Ann Surg 2011;254:860-865. Flum et al. conducted a retrospective analysis of Medicare Part A and Part B data from January 1, 2004 through December 31, 2008 (i.e., a comparison of outcomes before and after implementation of the 2006 NCD) obtained via the Research Data Assistance Center as well as enrollment data from the Social Security Administration and the Railroad Retirement Board. The authors stated that “Temporal trends in bariatric procedures and mortality were evaluated by quarter. Procedures/100,000 CMS enrollees, numbers of unique surgeons and sites performing bariatric procedures were calculated.” Outcomes evaluated were 90-day mortality and readmission within 90 days of surgery. Long term outcomes were not evaluated. Logistic regression modeling was used to compare outcomes pre- and post-NCD implementation. In reporting the results of the study, the authors noted that a “total of 47,030 CMS patients underwent bariatric procedures between January 1, 2004 to December 31, 2008. The rates of bariatric procedures increased from 15.0 procedures/100,000 CMS enrollees in 2004 to 21.9/100,000 in 2005, then decreased to 17.8/100,000 in 2006 and increased thereafter to 23.8/100,000 and 29.1/100,000 in 2007 and 2008, respectively. There was a significant increase in the mean age of those undergoing procedures from pre-NCD to post-NCD (51.0 +/- 11.1 years vs 54.0 +/- 11.7 years, p < 0.001), whereas the nonage entitlement beneficiary group (ie, medically disabled or renal failure and under age 65) decreased from 85.7% to 73.8% in the post-NCD era (p < 0.001). Women comprised 76.8% of the patients before pre-NCD and 74.7% of the patients post-NCD. Information regarding the BMI was not reported. The mean comorbidity index of bariatric cases increased slightly post-NCD (0.91 to 0.96, p < 0.001) and those with comorbidity scores ≥ 3 increased post-NCD (5.9% vs 7.4%, p < 0.001). The most common procedures in the entire study period were laparoscopic roux-en-y gastric bypass (LRYGB, 43.9%), open roux-en-y gastric bypass (ORYGB. 28.5%), and LAGB (3.8%). There was a significant change in the type of gastric bypass surgery performed from ORYGB to LRYGB between the pre-NCD era (61.2% open and 38.8% laparoscopic) and post-NCD era (20.8% open and 79.2% laparoscopic). There was a substantial increase in the LAGB procedures in the post-NCD (0% pre-NCD and 36.7% of all operations post-NCD). The numbers of sites and surgeons performing surgery decreased (absolute reductions of 48.6% and 47.8%, respectively) after the NCD and did not recover to reach pre-NCD levels." The authors noted that "Outcomes improved after the NCD (Table 2). The 90-day mortality rate pre-NCD was 1.5% (1.8% ORYGB, 1.1% LRYGB) and post-NCD was 0.7% (1.7% ORYGB, 0.8% LRYGB, 0.3% LAGB) (p < 0.001). After controlling for time trends (Fig. 3), the estimated pre-NCD 90-day mortality rate was 1.7% falling to 1.3% after the NCD (reduction in relative risk of 22.9%, p = 0.05)." More analysis of the 90-day mortality rate showed that the "unadjusted impact of the NCD on the rate of 90-day deaths was a reduction of 0.65% (p < 0.01). After controlling for covariates (age, sex, body mass index, and comorbidity index) and time trends this effect persisted, but the magnitude of the impact was lower - 0.36% (p = 0.03). After controlling for the change in procedure type, the observed reduction in mortality rate was no longer significant - 0.21% (p = 0.18)." The authors stated that in their study "adjusted analyses that accounted for temporal trends, sex, age, changes in procedure types and comorbidity index, found that reductions in 90-day mortality were largely accounted for by a shift to lower risk procedures and a change in patient characteristics (an increased proportion were Medicare-eligible related to age ≥ 65 years with fewer patients who were Medicare-eligible related to disability [age < 65]) and not necessarily the results of a shift to accredited centers." In conclusion, the authors noted that "the CMS bariatric surgery NCD was associated with a temporary reduction in case volume, a near halving of the 90-day mortality rate" and "significant decreases in serious complications and readmissions." In addition, the impact of the NCD on safety "in the CMS population seems to be accounted for mostly by shifts in procedure types and patient characteristics rather than in shifts of patients to accredited centers alone." Kwon S, Wang B, Wong E, Alfonso-Cristancho R, Sullivan SD and Flum DR. The impact of accreditation on safety and cost of bariatric surgery. Surg Obes Relat Dis 2012; ePub available online December 3, 2012. Kwon et al. performed a retrospective analysis of the MarketScan Commercial Claims and Encounter Database, which contains “claims for inpatient care for about 29.1 million patients < 65 years of age who have employer-sponsored insurance plans across broad geographic coverage.” The time frame was 2003 to 2009. Patients were included in this analysis if they were morbidly obese and did not have Medicare Supplemental insurance. The Medicare Supplemental database was used to identify centers performing bariatric surgery in the Medicare population after posting of the 2006 NCD; these centers were designated as COEs for the analysis. Centers that performed bariatric surgery on Medicare patients before but not after the NCD were designated as non-COEs for the analysis. The outcomes for the analysis were inpatient mortality and surgical complications. The goal of this analysis was to “assess the impact of COE accreditation on commercially insured patients distinct from other factors using a difference in difference approach between those having surgery at hospitals that did and did not become COEs before and after the NCD.” Kwon et al. chose the goal and methods for this analysis due to the results and limitations found in a prior analysis (Flum 2011). The authors noted that, in Flum, 2011, “our group evaluated fee-for-service CMS beneficiaries before and after the NCD and found that outcomes improved and costs were reduced but that this impact was most significantly influenced by a shift to safer procedures and to patients with lower risk clinical characteristics rather than through an independent effect of shifts to accredited centers. We found that distinguishing the effect of centers from shifts in patients and procedures and other temporal trends can be challenging. Because after the NCD, CMS beneficiaries could only receive treatment at COEs, teasing out the effect of center accreditation using Medicare data was even more challenging. Patients with commercial insurance are not necessarily limited to undergo bariatric surgery in COEs after the NCD. We hypothesized that commercially insured patients having surgery at non-COEs (after the NCD) might be an appropriate control to evaluate the effect of accreditation status on outcome compared with outcomes among patients with commercial insurance having surgery at COEs.” A total of 30,755 patients were included in the analysis; 14,989 had surgery during the 37 months prior to the NCD and 15,766 had surgery in the 43 months after the NCD. The overall mean (± SD) age was 43.9 (± 10.8) before the NCD and 43.9 (± 11.2) after the NCD. Females comprised 81.3% of the patients before the NCD and 78.5% after the NCD. The mean Charlson co-morbidity score was similar between the pre-NCD and post-NCD groups. The authors noted that “A total of 7896 patients underwent procedures at sites that became COEs after the NCD. Patients undergoing procedures in COEs in the post-NCD era were more likely to be males but were similar in terms of age and extent of co-morbid conditions compared with pre-NCD era (Table 1). In the COEs, there were significant shifts to more LRYGB and LAGB and less ORYGB. A total of 12,859 patients had surgery in non-COEs before and after the NCD. Patients at non-COE hospitals in the post-NCD era were similar in age but were more likely to be males and had a higher proportion of patients, with at least 1 co-morbidity compared with the pre-NCD era (Table 1). Significant shifts in procedures to more LRYGB and LAGB and away from ORYGB were also seen in the non-COEs.” With regards to outcomes, the authors reported an inpatient mortality rate of 0.3% before the NCD and 0.2% after the NCD (p = 0.1). In the COEs, the unadjusted in-hospital mortality rate was 0.3% before the NCD and 0.1% after the NCD (p = 0.01); in the non-COEs, the unadjusted in-hospital mortality rate was the same before and after the NCD (0.2%). For COEs, there was a statistically significant decrease in 90-day complications after the NCD compared to before the NCD (27.6% vs 36.4%, respectively; p < 0.05). The non-COEs also had a statistically significant decrease in the 90-day complication rate after the NCD compared to before the NCD (29.7% vs 36.3%, respectively; p < 0.001). To analyze the impact of accreditation on outcomes, Kwon et al. used a difference-in-difference model to account for temporal trends, varying patient risk and changes in procedural preferences over time. The authors reported that “After controlling for covariates (age, gender, and co-morbidity index), time trends (by adjusting for changes in outcomes pre- and post-NCD occurring in the non-COEs), and procedure types, there was a .04% decrease in the inpatient mortality rate (P = .1) at the COEs due to the NCD (Table 3).” However, a significant decrease in 90-day complication rates was found (- 2.7%; p = 0.01) at the COEs due to the NCD. The authors commented that the results of their analysis “suggest that the NCD produced a predominant shift of bariatric operations to COEs and a shift to safe procedures (LRYGB and LAGB) in the post-NCD period. Our DD regression model found that accreditation itself had a significant impact on 90-day complication and reoperation rates and not on inpatient mortality, readmissions, or payments.” Kwon et al. also noted the controversial issue of a volume-outcome relationship in bariatric surgery, which prompted the authors to state that “There may be other mechanisms by which the NCD may have exerted a center effect other than through shifts to higher volume hospitals. COE status through either accrediting body calls for multidisciplinary care team, education activities for patients, care pathways, mandatory reporting of outcomes and best practice infrastructure and personnel requirements. When evaluating COE effects on outcome, any of these factors may play a role, and distinguishing them is difficult if not impossible.” Kwon et al. noted a number of limitations with their analysis, including the use of data from an administrative database that did not contain clinical information that can provide important predictors of adverse outcomes such as BMI and a patient's functional status. The authors noted a second limitation in that the database "did not include hospital information such as their actual accreditation status at the time of the operation. Rather, we relied on a labeling strategy for the COE looking for those centers performing bariatric surgery on Medicare patients. Those centers that continued to perform surgery on CMS beneficiaries after the NCD were labeled COEs given that the risk of not being reimbursed likely compelled centers to perform surgery on CMS beneficiaries only if they were accredited. Patients may have been misclassified into the group undergoing operations at non-COEs when having their operations in the months before a center became a COE and some patients would have been misclassified as having their operation at a non-COE hospital if the hospital was a COE but performed no operations on CMS beneficiaries after the NCD. A third limitation concerned the difference-in-difference (DD) statistical methodology used to analyze the impact of accreditation on outcomes. The authors stated that "Analytically, although DD has been used to distinguish the effect of policy decision from other changing factors distinct from the NCD, an untestable assumption was made that a change in outcome in the COEs during our study period would have been the same as the change in the non-COEs had the NCD not occurred. Other insurers developed or adopted accreditation programs akin to the NCD criteria and may have affected non-COEs during this time period." The authors concluded that “the component of CMS’ NCD on bariatric surgery that related to shifting procedures to accredited centers did exert a positive effect on patient outcomes distinct from other factors. However, studies assessing the NCD’s impact on long-term effects, nonsafety outcomes such as weight loss and co-morbid condition improvements, costs, and quality of care are needed.” Nguyen NT, Nguyen B, Nguyen VQ, Ziogas A, Hohmann S and Stamos MJ. Outcomes of bariatric surgery performed at accredited vs nonaccredited centers. J Am Coll Surg 2012;215:467. Nguyen et al. conducted a retrospective analysis of data from the United HealthSystem Consortium database. Discharge data for all patients who underwent non-emergent open or laparoscopic Roux-en-Y gastric bypass, laparoscopic adjustable gastric banding or laparoscopic gastroplasty for morbid obesity between October 1, 2007 and December 31, 2009 were analyzed. COE status was first determined by searching the CMS website and then cross-referenced with the list on the ACS (both level 1 and 2) and the SRC websites. The goal was to compare the perioperative outcomes of bariatric procedures performed at COE versus non-COE centers. The primary outcome was in-hospital mortality; a