PUBLICATIONS

2025

Hiramoto B, Falahee BE, Muftah M, Flanagan R, Shah ED, Chan WW. Size of Pelvic Outlet as a Potential Risk Factor of Fecal Incontinence: A Population-Based Exploratory Analysis.. Clinical and translational gastroenterology. 2025;16(1):e00789. doi:10.14309/ctg.0000000000000789

INTRODUCTION: The impact of pelvic bone structure on fecal incontinence (FI) is unclear. We assessed the association between weight-adjusted pelvic area and FI.

METHODS: This was a population-based analysis of the National Health and Nutrition Examination Survey in 2005-2006. Participants who completed the bowel health survey and dual-energy x-ray absorptiometry were included.

RESULTS: On multivariable analysis of 2,772 participants, the lowest pelvic area quartile predicted increased FI compared with the third (odds ratio [OR]: 2.05, confidence interval [CI]: 1.18-3.56, P = 0.014) and fourth (OR: 1.94, CI: 1.02-3.70, P = 0.045) quartiles. Sex-stratified analyses found similar association among female patients only.

DISCUSSION: Small pelvic area on dual-energy x-ray absorptiometry is a potential risk factor of FI.

Hiramoto B, Muftah M, Flanagan R, Shah ED, Chan WW. Cost-Effectiveness Analysis of Current Treatment Options for Eosinophilic Esophagitis.. The American journal of gastroenterology. 2025;120(1):161-172. doi:10.14309/ajg.0000000000003104

INTRODUCTION: The management strategies for eosinophilic esophagitis include proton pump inhibitors (PPIs), swallowed topical corticosteroids (tCSs), elimination diets, and the biologic agent dupilumab, although there remains little guidance on the selection of initial treatment. We performed cost-effectiveness analyses to compare these approaches of first-line therapy.

METHODS: A Markov model was constructed from a payer perspective to evaluate the cost-effectiveness of first-line therapies for eosinophilic esophagitis, including PPI, tCS, and 6-food elimination diet (SFED), with crossover in treatments for primary and secondary nonresponse. The primary outcome was incremental cost-effectiveness ratio at 2 and 5-year time horizons. Secondary analyses included modeling from a societal perspective that also accounted for patient-specific costs, as well as a separate simplified model comparing dupilumab with tCS and PPI.

RESULTS: In the base-case scenario (5-year time horizon), the average costs were SFED: $15,296.81, PPI: $16,153.77, and tCS: $20,975.33 as initial therapy, with SFED being the dominant strategy (more effective/less costly), while PPI offered the lowest cost on a 2-year time horizon. From a societal perspective, PPI was the dominant initial strategy on both 2 and 5-year time horizons. Among pharmacologic therapies, PPI was the most cost-effective first-line option. Dupilumab was not cost-effective relative to tCS, unless the quarterly cost is reduced from $7,311 to $2,038.50 per price threshold analysis under permissive modeling conditions.

DISCUSSION: SFED was the most effective/least costly first-line therapy from the payer perspective while PPI was more cost-effective from the societal perspective. PPI is also the most cost-effective pharmacologic strategy. Dupilumab requires substantial cost reductions to be considered cost-effective first-line pharmacotherapy.

Chan WW, Sharma N, Gyawali P. The Role of Gastroesophageal Reflux in Airway Inflammation.. The American journal of gastroenterology. 2025;120(1):60-64. doi:10.14309/ajg.0000000000003205

Gastroesophageal reflux disease occurs when the barrier at the esophagogastric junction is weakened, allowing for transient relaxations of the lower esophageal sphincter or disruption of the esophagogastric junction. This leads to the refluxate traveling up the esophagus, and potentially into the pharynx, where it can be aspirated into the airway. The refluxate can cause a range of symptoms, including sore throat, coughing, wheezing, and shortness of breath, which may occur with or without visible airway inflammation. Both experimental and clinical studies have shown that aspirated refluxate can directly damage the airway lining and trigger immune responses that contribute to airway injury and inflammation. While traditional diagnostic tests for gastroesophageal reflux disease can identify abnormal reflux patterns, there is a need for more specific methods to predict airway inflammation or therapeutic outcomes related to reflux aspiration.

2024

Shah ED, Chan WW, Jodorkovsky D, et al. Optimizing the Management Algorithm for Heartburn in General Gastroenterology: Cost-Effectiveness and Cost-Minimization Analysis.. Clinical gastroenterology and hepatology : the official clinical practice journal of the American Gastroenterological Association. 2024;22(10):2011-2022.e5. doi:10.1016/j.cgh.2023.08.026

BACKGROUND AND AIMS: Heartburn is the most common symptom seen in gastroenterology practice. We aimed to optimize cost-effective evaluation and management of heartburn.

METHODS: We developed a decision analytic model from insurer and patient perspectives comparing 4 strategies for patients failing empiric proton pump inhibitors (PPIs): (1) PPI optimization without testing, (2) endoscopy with PPI optimization for all patients, (3) endoscopy with PPI discontinuation when erosive findings are absent, and (4) endoscopy/ambulatory reflux monitoring with PPI discontinuation as appropriate for phenotypic management. Health outcomes were respectively defined on systematic reviews of clinical trials. Cost outcomes were defined on Centers for Medicare and Medicaid Services databases and commercial multipliers for direct healthcare costs, and national observational studies evaluating healthcare utilization. The time horizon was 1 year. All testing was performed off PPI.

RESULTS: PPI optimization without testing cost $3784/y to insurers and $3128 to patients due to lower work productivity and suboptimal symptom relief. Endoscopy with PPI optimization lowered insurer costs by $1020/y and added 11 healthy days/y by identifying erosive reflux disease. Endoscopy with PPI discontinuation added 11 additional healthy days/y by identifying patients without erosive reflux disease that did not need PPI. By optimizing phenotype-guided treatment, endoscopy/ambulatory reflux monitoring with a trial of PPI discontinuation was the most effective of all strategies (gaining 22 healthy days/y) and saved $2183 to insurers and $2396 to patients.

CONCLUSIONS: Among patients with heartburn, endoscopy with ambulatory reflux monitoring (off PPI) optimizes cost-effective management by matching treatment to phenotype. When erosive findings are absent, trialing PPI discontinuation is more cost-effective than optimizing PPI.

Hiramoto B, Flanagan R, Muftah M, Shah ED, Chan WW. Centrally Distributed Adiposity as a Modifiable Risk Factor for Fecal Incontinence: United States Population-based Analysis.. Clinical gastroenterology and hepatology : the official clinical practice journal of the American Gastroenterological Association. 2024;22(9):1908-1916.e1. doi:10.1016/j.cgh.2024.04.002

BACKGROUND AND AIMS: Fecal incontinence (FI) is highly prevalent with substantial impacts on quality of life and health care utilization. The impact of obesity on FI remains unclear, with differing conclusions using body mass index (BMI) as a risk factor. We aimed to determine the association between obesity and FI, and whether this relationship is dependent on the distribution of adiposity (waist circumference-to-height ratio [WHtR]).

METHODS: This was a population-based analysis of the National Health and Nutrition Examination Survey, including participants who responded to the bowel health survey in 2005 to 2010. FI was defined by the accidental bowel leakage of solid stool, liquid, or mucus at least once in the past month. Stepwise multivariable logistic regression models were constructed to assess risk factors for FI.

RESULTS: A total of 7606 participants were included, with an overall FI prevalence of 9.2%. When stratified by quartiles of body measurements, FI was increasingly prevalent from the 1st to the 4th quartile for both WHtR (range, 5.3%-12.5%) and BMI (range, 7.1%-10.5%). WHtR was associated with FI and was a stronger predictor than BMI in all quartiles of body measurement. On multivariable analysis, WHtR remained a significant predictor of FI comparing the 4th with the 1st quartile of body measurements (odds ratio [OR], 1.77; 95% confidence interval [CI], 1.11-2.80; P = .017), whereas BMI was not. A WHtR cutoff of >0.592 optimized the Youden index in prediction of FI in the overall sample.

CONCLUSION: WHtR was independently associated with increased odds of FI in this nationally representative sample of United States adults, whereas BMI was not consistently correlated. This suggests bowel continence may depend more on how body mass is distributed.

Krause AJ, Carlson DA, Chan WW, et al. High Diagnostic Yield of Abnormal Endoscopic Findings in the Evaluation of Laryngopharyngeal Reflux.. Clinical gastroenterology and hepatology : the official clinical practice journal of the American Gastroenterological Association. 2024;22(8):1741-1743.e1. doi:10.1016/j.cgh.2024.01.012

Esophagogastroduodenoscopy (EGD) is recommended in patients with typical gastroesophageal reflux disease (GERD) symptoms (heartburn, regurgitation, chest pain) in the setting of proton pump inhibitor (PPI) nonresponse. EGD evaluates for erosive disease, assesses antireflux barrier integrity, excludes non-GERD conditions, and, in the absence of erosive findings, is followed by reflux testing.1,2 The diagnostic utility of EGD is less clear in the evaluation for laryngopharyngeal reflux (LPR), and the current reference standard is ambulatory reflux monitoring.1,3,4 This study of patients referred for evaluation of chronic laryngeal symptoms had the following aims: (1) to characterize endoscopic findings, (2) to discern whether findings differed between patients with or without concomitant esophageal reflux symptoms, and (3) to measure the association between endoscopic findings and objective GERD on ambulatory reflux monitoring.

Lo WK, Muftah M, Goldberg HJ, Sharma N, Chan WW. Concurrent abnormal non-acid reflux is associated with additional chronic rejection risk in lung transplant patients with increased acid exposure.. Diseases of the esophagus : official journal of the International Society for Diseases of the Esophagus. 2024;37(7). doi:10.1093/dote/doae020

Acid reflux has been associated with allograft injury and rejection in lung transplant patients; however, the pathogenic role of non-acid reflux remains debated. We aimed to evaluate the impact of concurrent abnormal non-acid reflux with acid reflux on chronic rejection in lung transplant patients with acid reflux. This was a retrospective cohort study of lung transplant recipients who underwent pre-transplant combined impedance-pH study off acid suppression. Only subjects with acid exposure >4% were included. Non-acid reflux (pH > 4) episodes >27 was considered abnormal per prior normative studies. Chronic rejection was defined as chronic lung allograft dysfunction (CLAD) per International Society for Heart and Lung Transplantation criteria. Time-to-event analyses were performed using Cox proportional hazards and Kaplan-Maier methods, with censoring at death, anti-reflux surgery, or last follow-up. In total, 68 subjects (28 abnormal/40 normal non-acid reflux) met inclusion criteria for the study. Baseline demographic/clinical characteristics were similar between groups. Among this cohort of patients with increased acid exposure, subjects with concurrent abnormal non-acid reflux had significantly higher risk of CLAD than those without on Kaplan-Meier analysis (log-ranked P = 0.0269). On Cox multivariable regression analysis controlling for body mass index, age at transplantation, and proton pump inhibitor use, concurrent abnormal non-acid reflux remained independently predictive of increased CLAD risk (hazard ratio 2.31, confidence interval: 1.03-5.19, P = 0.04). Presence of concurrent abnormal non-acid reflux in lung transplant subjects with increased acid exposure is associated with additional risk of chronic rejection. Non-acid reflux may also contribute to pathogenicity in lung allograft injury/rejection, supporting a potential role for impedance-based testing in this population.

INTRODUCTION: Adenoma per colonoscopy (APC) has recently been proposed as a quality measure for colonoscopy. We evaluated the impact of a novel artificial intelligence (AI) system, compared with standard high-definition colonoscopy, for APC measurement.

METHODS: This was a US-based, multicenter, prospective randomized trial examining a novel AI detection system (EW10-EC02) that enables a real-time colorectal polyp detection enabled with the colonoscope (CAD-EYE). Eligible average-risk subjects (45 years or older) undergoing screening or surveillance colonoscopy were randomized to undergo either CAD-EYE-assisted colonoscopy (CAC) or conventional colonoscopy (CC). Modified intention-to-treat analysis was performed for all patients who completed colonoscopy with the primary outcome of APC. Secondary outcomes included positive predictive value (total number of adenomas divided by total polyps removed) and adenoma detection rate.

RESULTS: In modified intention-to-treat analysis, of 1,031 subjects (age: 59.1 ± 9.8 years; 49.9% male), 510 underwent CAC vs 523 underwent CC with no significant differences in age, gender, ethnicity, or colonoscopy indication between the 2 groups. CAC led to a significantly higher APC compared with CC: 0.99 ± 1.6 vs 0.85 ± 1.5, P = 0.02, incidence rate ratio 1.17 (1.03-1.33, P = 0.02) with no significant difference in the withdrawal time: 11.28 ± 4.59 minutes vs 10.8 ± 4.81 minutes; P = 0.11 between the 2 groups. Difference in positive predictive value of a polyp being an adenoma among CAC and CC was less than 10% threshold established: 48.6% vs 54%, 95% CI -9.56% to -1.48%. There were no significant differences in adenoma detection rate (46.9% vs 42.8%), advanced adenoma (6.5% vs 6.3%), sessile serrated lesion detection rate (12.9% vs 10.1%), and polyp detection rate (63.9% vs 59.3%) between the 2 groups. There was a higher polyp per colonoscopy with CAC compared with CC: 1.68 ± 2.1 vs 1.33 ± 1.8 (incidence rate ratio 1.27; 1.15-1.4; P < 0.01).

DISCUSSION: Use of a novel AI detection system showed to a significantly higher number of adenomas per colonoscopy compared with conventional high-definition colonoscopy without any increase in colonoscopy withdrawal time, thus supporting the use of AI-assisted colonoscopy to improve colonoscopy quality ( ClinicalTrials.gov NCT04979962).