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Background: There is a lack of data on training benchmarks to define competence in colorectal EMR (C-EMR) among advanced endoscopy trainees (AETs). Previous pilot data from our group demonstrated a relatively low proportion of AETs achieve competence on key cognitive and technical aspects of C-EMR. We aimed to perform an interim analysis on C-EMR training among AETs and assess their performance using the EMR-STAT during the first trimester of their advanced endoscopy fellowship (AEF).
Methods: Prospective multicenter study evaluating AETs C-EMR training using the EMR-STAT. The tool was previously validated in the pilot study for standardized evaluation of key cognitive and technical C-EMR skills (Figure 1). A 4-point scoring system was used to grade these endpoints. Global rating was provided using a 10-point scoring system. For interim analysis, competence was defined as a score of 3 or 4 for each endpoint and ≥7 for overall assessment. Cumulative sum analysis was used to establish competence for cognitive and technical components of C-EMR and overall performance. Prior to the study, participating AETs completed questionnaire about their GI fellowship training in endoscopic resection.
Results: Twenty-five AETs from 18 institutions are enrolled in this ongoing study. On survey questionnaire, the AETs reported having performed a mean of 41.4 C-EMRs (interquartile range [IQR]: 10-50) before the onset of their AEF and most received cognitive training in C-EMR during their general GI fellowship (n=20; 80%). In the first trimester of their AEF, out of the 25 AETs, 15 have performed a mean of 9.1 C-EMRs (range 1-30). Mean lesion size was 26.7±11.6 and mean EMR time of 26.1±18.1 minutes. En-bloc resection rate for polyp sizes 11-20 mm was 41.3% (19/46). Competence in cognitive skills, such as assessment of polyp morphology and pit/vascular pattern, was achieved by AETs in 90.4% and 83.1%, respectively. AETs were graded as competent in submucosal lift injection and snare resection in 69.9% and 63.2%, respectively. Overall competence based on the global score was attained in 53.7% of the cases. On cumulative sum analysis, only 2 AETs crossed the competence threshold for cognitive skills and 1 AET for technical skills. The minimum threshold to achieve competence was 18 C-EMRs (Figure 2).
Conclusions: Standardized evaluation of competence in C-EMR training is critical for quality assurance in patient care. There was high variability in the number of C-EMRs performed by AETs and low overall en-bloc resection rates for polyps 11-20 mm in size. In aggregate, AETs were graded as competent in only half of the C-EMR cases and only 2 AETs have crossed the minimum threshold of competence. Ongoing data acquisition from this study will provide insight into the current state of C-EMR training during AEF and establish competence thresholds for quality metrics.

Figure 1. EMR Standardized Assessment Tool (EMR-STAT)

Figure 1. EMR Standardized Assessment Tool (EMR-STAT)

Figure 2. Representation of the learning curves among AETs by using cumulative sum (CUSUM) analysis for core cognitive and technical skills during C-EMR training.

Figure 2. Representation of the learning curves among AETs by using cumulative sum (CUSUM) analysis for core cognitive and technical skills during C-EMR training.

Background: The recently developed CAD EYE system (Fujifilm, Tokyo, Japan), which provides artificial intelligence (AI) -aided endoscopic diagnosis, has the potential to improve the detection for colorectal polyps. It is essential that gastroenterology trainees improve the quality of total colonoscopy (CS) operations and accelerate their technical progress. The aim of this study was to determine the utility of CAD EYE for CS by comparing endoscopic observation using CAD EYE with conventional endoscopic observation (i.e., white light imaging) in outpatients undergoing CS performed by gastroenterology trainees (i.e., beginner endoscopists).
Methods: This was a multi-center, randomized controlled trial at Ureshino Medical Center, Karatsu Red Cross Hospital and Saga University Hospital (UMIN000044031). The study received an academic research grant from the Japanese Society of Gastrointestinal Endoscopy in 2021. Patients were divided into group A (observed using CAD EYE) and group B (observed using white light imaging). Six gastroenterologists with limited experience in CS (i.e., trainees in their third or fourth year after graduation) performed CS using a back-to-back method in pairs with a gastroenterology specialist. The primary endpoint was the adenoma detection rate. The secondary endpoints were the adenoma miss rate (AMR) and 14 assessment of competency in endoscopy tool scores. The learning curve of each trainee was evaluated using the cumulative sum control chart.
Results: We analyzed 231 cases (113 in group A, 118 in group B) enrolled from May 2021 to March 2022. There was no difference in the adenoma detection rate of trainees between group A and group B (58.4% versus 61.0%, respectively; p=0.690). There was a significantly lower AMR (26.6% versus 39.7%, respectively; p=0.036) and number of missed adenomas per patient (0.5 versus 0.9, respectively; p=0.004) in group A compared with group B. Group A also scored significantly higher than group B on two items of the assessment of competency in endoscopy tool score—i.e., pathology identification (2.26 versus 2.07, respectively; p=0.030) and interpretation and identifying location of pathology (2.18 versus 2.00, respectively; p=0.038). For the cumulative sum learning curve of trainees, the number of cases in which multiple adenomas were missed by the six trainees who performed CS was lower in group A. Even after accumulating cases, the number of missed adenomas remained consistently lower in group A.
Conclusions: The use of CAD EYE can decrease the AMR and improve the ability to accurately locate and identify colorectal adenomas. Thus, CAD EYE is particularly useful for CS in beginning endoscopists.

Background:
Epidemiologic data highlight the suboptimal impact of screening and surveillance in Barrett’s esophagus (BE). PEEC and PEEN, similar to post-colonoscopy colorectal cancer, undermines the effectiveness of these practices. Using a population-based cohort study, we aimed to conduct a time trend analysis on PEEC and PEEN rates and neoplasia detection rate (NDR) among newly-diagnosed BE patients.

Methods:
This study was conducted in Denmark, Finland and Sweden from 2006-2020. We included data from the national patient, cancer, causes of death and prescribed drug registries. Patients with newly diagnosed BE were included and excluded patients with prior upper GI cancer, or BE endoscopic therapy. Demographics, country, year of diagnosis, smoking, Charlson comorbidity index score, medications, and hospital volume were collected. PEEC and PEEN were defined as EAC or HGD/EAC, respectively, diagnosed 30-365 days from the index endoscopy that diagnosed BE. NDR was defined as HGD/EAC diagnosed from 0-29 days and incident HGD/EAC was diagnosed >365 days. Patients were followed until diagnosis of HGD/EAC, death or end of study period. Incidence rates (IR)/100,000 person-years (pyrs) for the entire study cohort and for 3 calendar periods: 2006-2010, 2011-2015 and 2016-2020 and incidence rate ratios (IRR) with 95% CI with Poisson regression were calculated. A graphical representation of the predicted probability of EAC by month in the first year after entry is reported and for the 3 calendar periods.

Results:
20,588 newly diagnosed BE patients (mean age 64.6 years, 67% men, Sweden 64.6%, Denmark 14.8% and Finland 20.6%) were included. 279 patients were diagnosed with EAC: NDR (41, 14.6%), PEEC (65, 23.2%) and incident EAC (173, 62%). Overall IRs for NDR, PEEC and incident EAC were 2521 (95% CI 1857-3425), 369 (289-470) and 199 (172-231) /100,000 pyrs. The IRs/100,000 pyrs in the 3 calendar periods for NDR and PEEC were: 2006-2010: 3151 and 194, 2011-2015: 2633 and 271 and 2016-2020: 2080 and 590, respectively (Table 1). Diagnoses of HGD were only available in Swedish database, where 279 patients were diagnosed with HGD/EAC: NDR (41, 14.6%), PEEN (48, 17.2%) and incident HGD/EAC (190, 68,1%). Time-trends in IRs for NDR and PEEN in Sweden were: 2006-2010: 4587 and 260; 2011-2015: 3752 and 333 and 2016-2020: 3501 and 669, respectively (Table). Figure highlights the probability of EAC in the first year after index endoscopy overall and based on age, sex and year of endoscopy. Increasing age and male sex were significant predictors for NDR and PEEC.

Conclusions:
Despite improvements in endoscopic technology, this study showed a decline in NDR with a concurrent 2-3 time increase in PEEC and PEEN rates. Future studies should assess the impact of interventions (education, quality metrics and artificial intelligence) in improving NDR and reducing PEEC/PEEN in practice.

<b>Table: Incidence rates and incidence rate ratios for NDR, PEEC/PEEN and incident HGD/EAC – overall and based on the three calendar periods</b>

Table: Incidence rates and incidence rate ratios for NDR, PEEC/PEEN and incident HGD/EAC – overall and based on the three calendar periods

<b>Figure 1: Probability of PEEC in the overall cohort and based on sex, age and year of diagnosis of Barrett’s esophagus</b>

Figure 1: Probability of PEEC in the overall cohort and based on sex, age and year of diagnosis of Barrett’s esophagus

Background:
Single center studies suggest that adenoma detection rates (ADR) vary between gastroenterologists and surgeons. The generalizability of these findings is unclear. We sought to compare ADR between gastroenterologists and surgeons in the US Veterans Health Administration national healthcare system and to examine the association of patient demographic factors with ADR.

Methods:
We identified colonoscopy procedures of all indications using CPT codes from VA national electronic health records between October 2018-September 2022. We used a previously validated text recognition algorithm to determine histology from the associated pathology reports of patients aged 45-75. We classified providers from administrative codes for surgery and gastroenterology. After excluding providers with fewer than 50 colonoscopy procedures, we calculated each provider ADR as the percentage of colonoscopies with at least one adenoma or adenocarcinoma. We compared average ADR in surgeons and gastroenterologists using a 2-tailed t-test and compared the proportion of providers with ADR <30% using a chi-square test. We also calculated provider ADR in patients with different demographics (gender, race, ethnicity, geographic location and FIT+ testing within one year of colonoscopy) and used a generalized linear model to compare the ADRs before and after adjustment for patient demographics.

Results:
We identified 669,434 colonoscopies by 1,095 unique providers. Gastroenterologists (n=906; 82.7%) conducted 88.8% (n=594,710). The patient demographics are shown in the Table. ADR of surgeons (41.4%; 95% CI [39.5, 43.4]) was significantly lower than that of gastroenterologists (53.33%; 95% CI [52.7, 54.0]), p<0.0001 both before and after adjusting for differences in patient demographics. ADRs <30% were observed in 38 of 189 (20.1%) surgeons compared to 19 of 906 (2.1%) of gastroenterologists; p<0.0001. Surgeon ADRs were distributed across proportionally lower values than gastroenterology ADRs (Figure). Within both provider groups, higher ADRs were observed in men vs. women, in whites vs. non-whites, and in patients with a prior vs. no prior FIT test positive, though surgeon ADR remained consistently lower than gastroenterologist ADR. Among the colonoscopies performed after a positive FIT test, the ADR was significantly lower for surgeons (57.3%; 95% CI [53.7, 60.9]) than gastroenterologists (65.9%; 95% CI [64.8, 67.0]), p<0.0001.

Conclusion:
In this large US national healthcare system colonoscopy cohort, surgeons had a significantly lower ADR for colonoscopy of all indications and a higher proportion of endoscopists with ADRs < 30% than gastroenterologists, irrespective of patient demographics. Our findings highlight potential opportunities for targeted quality improvement and further evaluation of colonoscopy training parameters for surgical specialties.

Table. Adenoma Detection Rates of Gastroenterologists and Surgeons by Patient Demographics

Table. Adenoma Detection Rates of Gastroenterologists and Surgeons by Patient Demographics

Figure: Distribution Histograms of Gastroenterologist and Surgeon Adenoma Detection Rates.<br /> Note: Lines represent the 2-period moving averages of number of providers within each ADR range for GIs and surgeons, respectively.

Figure: Distribution Histograms of Gastroenterologist and Surgeon Adenoma Detection Rates.
Note: Lines represent the 2-period moving averages of number of providers within each ADR range for GIs and surgeons, respectively.

INTRODUCTION:
Improvements in colonoscopy quality are associated with reductions in interval colorectal cancer death. However, measurement of colonoscopy quality in practice remains challenging. We aim to describe and validate an interactive tool for artificial intelligence (AI) assessment of colonoscopy quality (AI-CQ) using recorded videos.

METHODS:
Based on quality guidelines, metrics were selected for AI development: insertion time (IT), withdrawal time (WT), retroflexion frequency, polyp detection rate (PDR), polyps per colonoscopy (PPC), and number of right colon evaluations. We also developed two novel metrics: withdrawal time excluding polypectomy time (WT-PT) and high-quality withdrawal time (HQ-WT; withdrawal time with clear colon image). The AI model was pre-trained using a self-supervised vision transformer on unlabeled colonoscopy images (n = 1x10⁷) mutually exclusive from all other datasets. The vision transformer model was finetuned for multi-label classification on another mutually exclusive colonoscopy image dataset (n = 9854) using anatomical, procedural, and pathological labels (label n = 14). During inference, colonoscopy video frame predictions were generated at a resolution of one frame per second and employed a binary threshold of ≥ 0.5 to denote presence; these predictions were subsequently used to calculate all metrics. A timeline of video predictions and metric calculations were presented to clinicians in addition to the raw video using a web-based application. The model was developed using videos at a single hospital and externally validated using 50 screening and surveillance colonoscopy videos from 6 colonoscopists at a second hospital.

RESULTS:
The interactive AI-CQ tool is presented (Figure). The cecum was reached in 48/50 cases; AI-CQ accuracy to identify cecal intubation was 88%. In 6 cases, AI-CQ did not identify the cecum due to inadequate bowel preparation obscuring landmarks (n=4) and failure to recognize landmarks (n=2).

IT (p = 0.26) and WT (p = 0.34) were similar between manual and AI-CQ measurements and significantly (p < 0.001) positively correlated (Table). On average, HQ-WT was 45.9% (IQR: 14) of, and significantly correlated with (ρ = 0.85; p < 0.001), normal WT time. Mean WT-PT was 567s, similar to mean normal colonoscopy WT (558s).

AI-CQ produced similar PDR (p = 0.66) and PPC compared to manual (p = 0.34). Rectal retroflexion was correctly identified in 95.2% of colonoscopies and the number of right colon evaluations in all colonoscopies.

DISCUSSION:
AI-CQ can be utilized to rapidly measure quality and facilitates AI-augmented review of inspection and polypectomy technique to provide actionable feedback. Further, novel inspection metrics such as WT-PT and HQ-WT, which can only be feasibly calculated by AI, may prove beneficial but require further study.

The AI-CQ is an interactive tool that automatically identifies multiple landmark events during a colonoscopy (e.g., the time the cecum is reached, when a polyp is identified, what tool is utilized to remove the polyp, etc.). This facilitates measurement of multiple colonoscopy metrics as well as allows the reviewer to rapidly watch a segment of the colonoscopy video to provide actionable feedback.

The AI-CQ is an interactive tool that automatically identifies multiple landmark events during a colonoscopy (e.g., the time the cecum is reached, when a polyp is identified, what tool is utilized to remove the polyp, etc.). This facilitates measurement of multiple colonoscopy metrics as well as allows the reviewer to rapidly watch a segment of the colonoscopy video to provide actionable feedback.

Manual and Artificial Intelligence Colonoscopy Quality (AI-CQ) timings and polyp detection. Data presented as median (IQR) unless noted. ** p < 0.001

Manual and Artificial Intelligence Colonoscopy Quality (AI-CQ) timings and polyp detection. Data presented as median (IQR) unless noted. ** p < 0.001

Background: GI endoscopy procedures are critical for the screening, diagnosis, and treatment of a variety of patient signs/symptoms. However, similar to other medical disciplines, they are a source of environmental waste generation and energy consumption in form of plastic, sharps, personal protective equipment (PPE), cleaning supplies and energy.

Methods: We prospectively collected data on total waste generation of a single large academic endoscopy unit over a 2-month period (May-June 2022). During this time period, detailed data on items used for every patient were collected from the point of patient entry to the endoscopy unit until discharge including procedure type, accessories used, IV tubing, number of biopsy jars, linen, PPE usage etc. In addition, reprocessing related waste generation for each procedure and energy utilization for the unit (endoscopy equipment, lights, computers etc.) for each day were also collected. The waste generated was stratified into biohazardous, non-biohazardous, or potentially recyclable items (to determine opportunities to improve/maximize recycling of waste). No patient information was collected, and the study was approved by the IRB.

Results: We prospectively analyzed waste generation for 450 consecutive procedures over a 2-month period. The total waste generated during this time period was 1398.6 kg - 61.6% directly going to landfill, 33.3% biohazard waste and 5.1% sharps. The average per procedure waste directly going to landfill was 2.19 kg which approximates to 9,189 kg for an entire year or 219 kg/100 procedures. 20% of the total waste generated was potentially recyclable (i.e. plastic CO₂ tubing, O₂ connector, syringes etc.). This could reduce total waste going to landfill by 8.6 kg per day (2,580 kg per year) or 61 kg per 100 procedures (Figure 1). Endoscope reprocessing generated 194 gallons of liquid waste (=735.26 kg.) per day or 1385 gallons per 100 procedures. In total, the annual waste generation approximated the size of 2 football fields. Finally, energy consumption in the endoscopy unit was 277.1 kW hour energy per day (=8.2 gallons of gasoline) or ~1980 kW hour per 100 procedures. Energy consumption for 100 procedure amounts to 1200 miles of distance (i.e. Seattle to San Diego) traveled by an average fuel efficiency car.

Conclusion: On average, every 100 routine GI endoscopy procedures (EGD/colonoscopy) are associated with 218 kg. landfill waste generation, and 2000kW hour energy consumption. Potentially recyclable materials account for 20% of the total waste – this can be a simple initial step to reduce waste going to landfill. These data could serve as an actionable model for health-systems to reduce total waste generation, landfill, and water waste towards environmentally sustainable endoscopy units.

Figure 1. Average daily waste distribution in the endoscopy unit

Figure 1. Average daily waste distribution in the endoscopy unit

Table 1. Total waste production and energy per day and per 100 procedures

Table 1. Total waste production and energy per day and per 100 procedures

Background and aims: Endoscopic transpapillary gallbladder stenting (ETGS) and endoscopic ultrasound-guided transmural stenting (EUGS) has been proposed as an alternative treatment in patients with acute cholecystitis (AC) who are not surgical candidate. We compared the outcomes of ETGS and EUGS in patients with AC at high surgical risk during an18-month follow-up.
Methods: We enrolled patients with AC at high surgical risk (Charlson Comorbidity Index ≥6) between 2021-2022. Patients were randomized to group A (received ETGS) and group B (received EUGS). A 7-Fr, 15-cm double-pigtail plastic stent (DPS) was used for ETGS. A 15- or 16-mm lumen-apposing metal stent (LAMS) or a 10x60 mm fully covered self-expandable metal stent with a 7-Fr/5-cm DPS for metallic stent anchoring (FCSEMS-DPS) were used for EUGS.
Result: We randomized 42 patients into group A (n=22) and group B (n=20). Group A had lower technical success rate (TSR) but did not reach statistical significance when compared to group B [19/22 (86.4%) vs. 20/20 (100%); p=0.09] and had similar clinical success rate (CSR) [19/19 (100%) vs. 20/20 (100%); p=1.00] (Table). Three patients did not achieve ETGS due to an acute angle of the cystic duct(n=1) and cystic duct stone obstructing a guidewire advancing into the gallbladder(n=2). The management after ETGS failure included subsequent EUGS (n=2) and EUS-guided gallbladder aspiration (n=1). Procedure-related adverse events (PAE) rates did not differ between group A and B (13.6% vs. 20%; p=0.58). In group A, 2 patients had recurrence after 9 months (at day 285 and 436) due to stent occlusion and both received ETGS stent replacement. In group B, FCSEMS-DPS migration was seen in one patient on routine plain film at 2 weeks after EUGS and this patient developed early recurrence at day 71, eventually this patient had LAMS as a replacement. At 3, 6, 12, and 18 months, the rates of recurrent AC in those who still survived were not statistically different [groups A and B: 0% (0/20) vs. 5.6% (1/18); p=0.56, 0% (0/18) vs. 7.1% (1/14); p=0.35, 5.9% (1/17) vs. 8.3% (1/12); p=0.47 and 13.3% (2/15) vs. 9.1% (1/11); p=0.64, respectively]. Death unrelated to gallstone was noted in 4 and 7 patients in group A and B, respectively (range 8-563 days after procedure). Kaplan-Meier plots demonstrated that the rates of recurrence were comparable between the two groups (p=0.61) during follow-up (median 394 days; range 8-700 days) (Figure).
Conclusion: ETGS tended to have a lower TSR compared to EUGS with comparable CSR and PAEs in the patients with AC who are not surgical candidate. During an 18-month follow-up, recurrent AC tended to be higher in ETGS group due to stent occlusion that developed at 9 months or later. For EUGS, early tubular stent migration was the only cause for recurrence, LAMS should be more preferred to prevent stent migration.

<b>Table. Outcomes of ETGS and EUGS in patients with acute calculous cholecystitis at high surgical risk (n=42)</b>

Table. Outcomes of ETGS and EUGS in patients with acute calculous cholecystitis at high surgical risk (n=42)

<b>Figure.</b><b> Kaplan-Meier analysis demonstrated </b><b>r</b><b>ecurrence-free survival curve in patients with acute calculous cholecystitis at high surgical risk who received ETGS and EUGS and had clinical success (n=39) </b>

Figure. Kaplan-Meier analysis demonstrated recurrence-free survival curve in patients with acute calculous cholecystitis at high surgical risk who received ETGS and EUGS and had clinical success (n=39)

Background: Several studies have demonstrated targeted next-generation sequencing (NGS) of biliary brushings and/or biopsy specimens can improve the identification of neoplastic bile duct strictures. However, these reports have largely been limited to retrospective analyses, single institutional experiences, and/or utilized NGS panels that were insufficiently comprehensive to account for the diversity of neoplasms that can cause a neoplastic stricture. The aim of this study was to prospectively evaluate NGS on a multi-institutional cohort of patients with a bile duct stricture in real-time.

Methods: Among seven institutions within a 3-year period, 1208 biliary specimens from 754 patients were submitted for targeted NGS that included two panels: a 28-gene NGS panel with 167 fusion genes (n=218) and a 161-gene NGS panel with 823 fusion genes (n=536). The NGS results were correlated with clinical presentation, history of primary sclerosing cholangitis (PSC), pathologic findings and follow-up. A stricture was designated as benign or neoplastic based on diagnostic pathology and/or a clinical course of >12 months.

Results: The sensitivity and specificity of NGS of biliary specimens for neoplasia were 82% and 96%, respectively. In comparison, pathologic evaluation had a sensitivity of 49% and a specificity of 100%. The combination of NGS and pathologic evaluation improved the sensitivity of both assays to 88%. Moreover, the addition of NGS to pathologic evaluation improved the sensitivity of biliary brushings from 36% to 84% and biliary biopsies from 47% to 87%. An expanded NGS panel (161 genes and 823 fusion genes) also showed improved sensitivity from 73% to 87% over a more limited panel (28 genes and 167 fusion genes). Repeat pathologic and NGS testing was performed for 118 patients and overall sensitivity increased to 91% but maintained a high specificity of 94%. Among 96 PSC patients, NGS had an 84% sensitivity as compared to pathologic evaluation with a 30% sensitivity. Of note, no statistically significant differences were observed in the performance of NGS based on the location of the patient’s stricture.

Conclusions: Through a prospective, multi-institutional study, the combination of NGS and pathologic evaluation of both biliary brushings and biopsy specimens improved the detection of neoplastic bile duct strictures. Furthermore, targeted NGS increased the sensitivity of identifying neoplasia in PSC patients.

Background: Analysis from the Centres for Disease Control and Preventions (CMS) suggests the prevalence of obesity in the U.S. was 41.9% in 2017, and is expected to increase to 50% by 2030. Obesity is a major risk factor for multiple chronic diseases (such as type II diabetes and cardiovascular disease) and can lead to reduced quality of life as well as increased risk of death. Lifestyle modification (LM) has traditionally been a first-line treatment for adults with obesity but recent guidelines recommend bariatric intervention. Endoscopic sleeve gastroplasty (ESG) is a reversible, endoluminal organsparing bariatric procedure that has demonstrated sustained weight loss in people with obesity. The MERIT randomized, controlled trial (RCT) recently showed that ESG with concomitant LM (‘ESG’) led to significant and durable additional excess weight loss versus LM alone (‘LM’) among adults with class I (BMI 30.0-34.9 kg/m2) and class II obesity (BMI 35.0-39.9 kg/m2) as well as improvements in obesity-related comorbidities including type 2 diabetes.
Aim: We aimed to provide the first US cost-utility analysis of ESG vs LM among people with class II obesity.
Methods: The model was built from the perspective of the commercial US payor and methods were aligned with ISPOR recommendations. We used a 6-state Markov model that included 5 BMI-based health states and an additional absorbing death state (Figure 1). Clinical parameters were informed the MERIT Trial. Six-month cycles were used in the first year to reflect the significant and rapid weight loss observed with ESG and annual cycles were used thereafter. Estimates of utility for each health state, disutilities for adverse events, and the incidence of obesity-related comorbidities were based on published literature. One-way sensitivity and probabilistic sensitivity analyses were undertaken.
Results: ESG is highly cost-effective compared to LM from the US perspective. The base-case incremental cost-effectiveness ratio (ICER) for ESG vs LM was $9,281/QALY. The estimated incidence of diabetes had the largest impact on the ICER in one-way sensitivity analyses, though ESG was consistently cost effective across all sensitivity and dominant (cost-saving and improving quality of life) in scenario analyses with no upper bound ICER estimate exceeding $23,000/QALY gained, at a willingness to pay ratio of $50,000/QALY.
Conclusion: Compared with LM alone, ESG is a highly cost-effective treatment option for adults and should be used in selected patients requiring bariatric intervention from the US commercial perspective. Further clinical studies are required the cost effectiveness of ESG with other bariatric obesity interventions including LSG and pharmacological agents.

Cost Utility Model Structure

Christopher Chapman

University of Chicago

Appearances