Hiramoto B, Flanagan R, Muftah M, Shah ED, Chan WW. Centrally Distributed Adiposity as a Modifiable Risk Factor for Fecal Incontinence: U.S. Population-Based Analysis. Clinical gastroenterology and hepatology : the official clinical practice journal of the American Gastroenterological Association. Published online 2024. 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 healthcare utilization. The impact of obesity on FI remains unclear, with differing conclusions using BMI as 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 2005-2010. 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 7,606 participants were included, with an overall FI prevalence of 9.2%. When stratified by quartiles of body measurements, FI was increasingly prevalent from 1st to 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 to the 1st quartile of body measurements (OR:1.77, CI:1.11-2.80, p=0.017), 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 US adults, whereas BMI was not consistently correlated. This suggests bowel continence may depend more on how body mass is distributed.

Krause AJ, Greytak M, Kaizer AM, et al. Diagnostic Yield of Ambulatory Reflux Monitoring Systems for Evaluation of Chronic Laryngeal Symptoms. The American journal of gastroenterology. 2024;119(4):627-634. doi:10.14309/ajg.0000000000002557

INTRODUCTION: Among patients with chronic laryngeal symptoms, ambulatory reflux monitoring off acid suppression is recommended to evaluate for laryngopharyngeal reflux (LPR). However, reflux monitoring systems are diverse in configuration and monitoring capabilities, which present a challenge in creating a diagnostic reference standard in these patients. This study aimed to compare diagnostic yield and performance between reflux monitoring systems in patients with chronic laryngeal symptoms.

METHODS: This multicenter, international study of adult patients referred for evaluation of LPR over a 5-year period (March 2018-May 2023) assessed and compared diagnostic yield of pathologic gastroesophageal reflux (GER+) on ambulatory reflux monitoring off acid suppression.

RESULTS: Of 813 patients, 296 (36%) underwent prolonged wireless pH, 532 (65%) underwent 24-hour pH-impedance monitoring, and 15 (2%) underwent both tests. Overall diagnostic yield for GER+ was 36% and greater for prolonged wireless pH compared with that for 24-hour pH-impedance monitoring (50% vs 27%; P < 0.01). Among 15 patients who underwent both prolonged wireless pH and 24-h pH-impedance monitoring, concordance between systems for GER+ was 40%. The most common source of discordance was strong evidence of GER+ across multiple days on prolonged wireless pH compared with no evidence of GER+ on pH-impedance.

DISCUSSION: In this multicenter international study of patients with chronic laryngeal symptoms referred for LPR evaluation, diagnostic yield of ambulatory reflux monitoring off acid suppression was 36% and rose to 50% when using wireless pH monitoring. In patients referred for chronic laryngeal symptoms, 24-hour pH-impedance monitoring may risk a low negative predictive value in patients with unproven GER+ disease.

Lechien JR, Vaezi MF, Chan WW, et al. The Dubai Definition and Diagnostic Criteria of Laryngopharyngeal Reflux: The IFOS Consensus. The Laryngoscope. 2024;134(4):1614-1624. doi:10.1002/lary.31134

OBJECTIVE: The objective of this work was to gather an international consensus group to propose a global definition and diagnostic approach of laryngopharyngeal reflux (LPR) to guide primary care and specialist physicians in the management of LPR.

METHODS: Forty-eight international experts (otolaryngologists, gastroenterologists, surgeons, and physiologists) were included in a modified Delphi process to revise 48 statements about definition, clinical presentation, and diagnostic approaches to LPR. Three voting rounds determined a consensus statement to be acceptable when 80% of experts agreed with a rating of at least 8/10. Votes were anonymous and the analyses of voting rounds were performed by an independent statistician.

RESULTS: After the third round, 79.2% of statements (N = 38/48) were approved. LPR was defined as a disease of the upper aerodigestive tract resulting from the direct and/or indirect effects of gastroduodenal content reflux, inducing morphological and/or neurological changes in the upper aerodigestive tract. LPR is associated with recognized non-specific laryngeal and extra-laryngeal symptoms and signs that can be evaluated with validated patient-reported outcome questionnaires and clinical instruments. The hypopharyngeal-esophageal multichannel intraluminal impedance-pH testing can suggest the diagnosis of LPR when there is >1 acid, weakly acid or nonacid hypopharyngeal reflux event in 24 h.

CONCLUSION: A global consensus definition for LPR is presented to improve detection and diagnosis of the disease for otolaryngologists, pulmonologists, gastroenterologists, surgeons, and primary care practitioners. The approved statements are offered to improve collaborative research by adopting common and validated diagnostic approaches to LPR.

LEVEL OF EVIDENCE: 5 Laryngoscope, 134:1614-1624, 2024.

Lodhia NA, Hiramoto B, Horton L, Goldin AH, Thompson CC, Chan WW. Obesity Is Associated with Altered Rectal Sensitivity in Chronic Constipation. Digestive diseases and sciences. 2024;69(3):884-891. doi:10.1007/s10620-023-08246-z

BACKGROUND: Defecation dysfunction may contribute to chronic constipation (CC), but the impact of obesity on anorectal physiology in CC remains unclear. We aimed to evaluate the relationship between obesity and anorectal function on physiologic testing in patients presenting with CC.

METHODS: This was a retrospective cohort study of consecutive adults who underwent high resolution anorectal manometry (HRAM) at a tertiary center for CC. Patient demographics, clinical history, surgical/obstetric history, medications, and HRAM results were reviewed. Patients were classified into obese (BMI > 30 kg/m2) vs non-obese (BMI < 30 kg/m2) groups at the time of HRAM. Fisher-exact/student t-test for univariate analyses and general linear regression for multivariable analysis were performed.

RESULTS: 383 adults (mean 50.3 years; 85.8% female) with CC were included. On HRAM, patients with obesity had lower anal sphincter resting tone (37.3 vs 48.5 mmHg, p = 0.005) and maximum squeeze pressure (104.8 mmHg vs 120.0 mmHg, p = 0.043). No significant differences in dyssynergia (61% vs 53%, p = 0.294) and failed balloon expulsion (18% vs 25%, p = 0.381) were found between obese and non-obese groups. On balloon distention testing, the maximum tolerated (163.5 vs 147.6 mL, p = 0.042) and urge sensation (113.9 vs 103.7 mL, p = 0.048) volumes were significantly increased among patients with obesity. After adjusting for potential confounders, obesity remained independently associated with increased maximum tolerated volume (β-coefficient 13.7, p = 0.049).

CONCLUSION: Obesity was independently associated with altered rectal sensitivity among patients with CC. Altered rectal sensation may play an important role in CC among patients with obesity. Anorectal physiology testing should be considered to understand the pathophysiology and guide management.

Shah ED, Curley MA, Patel A, Lo WK, Chan WW. Heartburn Relief is the Major Unmet Need for Drug Development in Gastroesophageal Reflux Disease: Threshold Value Analysis. Clinical gastroenterology and hepatology : the official clinical practice journal of the American Gastroenterological Association. Published online 2024. doi:10.1016/j.cgh.2024.01.049

BACKGROUND AND AIMS: Heartburn symptoms contribute to healthcare-seeking among patients with gastroesophageal reflux disease (GERD). Despite clinical guidance, management is often dictated by insurance restrictions. Several potassium-competitive acid blockers (PCAB) are under development as a new class of therapy. We performed economic analyses to align GERD drug development with the needs of gastroenterologists, insurers and patients in a value-based environment.

METHODS: A decision-analytic model was constructed to compare vonoprazan 20mg daily (an example of a potassium-competitive acid blocker[PCAB]), common over-the-counter or prescription proton pump inhibitor (PPI) regimens, and no treatment over a one-year time horizon. Clinical responses were evaluated based on the proportions of heartburn-free days in a recent phase 3 multicenter trial. Healthcare utilization for persistent reflux symptoms was derived from national observational studies compared to healthy controls. Costs and quality-adjusted life years [QALY] were reported.

RESULTS: Without insurance coverage for appropriate therapy, patients spend $4,443 and insurers spend $3,784 on average per year for inadequately treated GERD symptoms. Our model estimates that PCABs could save at least $3,000 in annual costs to patients and insurers, could generate QALY gains (+0.06/year), and could be cost-saving to insurers as a covered option at a price up to $8.57/pill, if these drugs are able to demonstrate similar effectiveness to PPIs in future trials evaluating heartburn relief and erosive esophagitis healing to regulators. Threshold prices reflect pricing after all pharmacy benefits manager rebates and discounts.

DISCUSSION: We demonstrate that aiming GERD-related drug development toward heartburn relief appears critical to align cost-effective incentives for industry and insurers with those of patients and gastroenterologists.

Muftah M, Barshop K, Redd WD, Goldin AH, Lo WK, Chan WW. Baseline Peripheral Eosinophil Count Independently Predicts Proton Pump Inhibitor Response in Eosinophilic Esophagitis. Journal of clinical gastroenterology. 2024;58(3):242-246. doi:10.1097/MCG.0000000000001845

GOALS: To assess the predictive value of baseline peripheral absolute eosinophil counts (AECs) for proton pump inhibitor (PPI) response in eosinophilic esophagitis (EoE).

BACKGROUND: PPI leads to histologic remission in  50% of EoE patients, although there are few distinguishing clinical features between PPI-responsive (PPI-r-EoE) and nonresponsive (PPI-nr-EoE) diseases. Peripheral eosinophilia is present in  50% of EoE cases and is associated with eosinophil density on esophageal biopsy and worse clinical outcomes. The association between peripheral eosinophilia and PPI-responsiveness in EoE remains unclear.

STUDY: This is a retrospective cohort study of adult EoE patients at a tertiary center between 2012 and 2016. All patients underwent twice daily PPI trials for ≥8 weeks followed by repeat esophageal biopsies and were classified as PPI-r-EoE or PPI-nr-EoE based on histologic response (<15 eosinophils/high power field). Baseline peripheral AEC was obtained within 1 month before index endoscopy. Analyses were performed using Fisher exact/Student t test (univariate) and logistic regression (multivariable).

RESULTS: One hundred eighty-three patients (91 PPI-nr-EoE and 92 PPI-r-EoE) were included. Mean peripheral AEC was higher among PPI-nr-EoE patients (0.41 vs 0.24 K/µL, P = 0.013). Baseline peripheral eosinophilia (>0.5 K/µL) was more prevalent among patients with PPI-nr-EoE (70.4% vs 45.5%, P = 0.023) and a history of food impaction (51.9% vs 23.7%, P = 0.0082). On multivariable analyses, peripheral eosinophilia remained an independent predictor for PPI response (adjacent odds ratio = 2.86, CI: 1.07-7.62, P = 0.036) and food impaction (adjacent odds ratio = 2.80, CI: 1.07-7.35, P = 0.037).

CONCLUSIONS: Baseline peripheral eosinophilia independently predicts PPI nonresponse and food impaction in EoE patients. Peripheral AEC may help therapy selection in EoE and prevent delays in achieving histologic remission.

Shah ED, Ahuja NK, Brenner DM, et al. Optimizing the Management Algorithm for Adults With Functional Constipation Failing a Fiber/Laxative Trial in General Gastroenterology: Cost-Effectiveness and Cost-Minimization Analysis. The American journal of gastroenterology. 2024;119(2):342-352. doi:10.14309/ajg.0000000000002515

INTRODUCTION: Anorectal function testing is traditionally relegated to subspecialty centers. Yet, it is an office-based procedure that appears capable of triaging care for the many patients with Rome IV functional constipation that fail empiric over-the-counter therapy in general gastroenterology, as an alternative to empirical prescription drugs. We aimed to evaluate cost-effectiveness of routine anorectal function testing in this specific population.

METHODS: We performed a cost-effectiveness analysis from the patient perspective and a cost-minimization analysis from the insurer perspective to compare 3 strategies: (i) empiric prescription drugs followed by pelvic floor physical therapy (PFPT) for drug failure, (ii) empiric PFPT followed by prescription drugs for PFPT failure, or (iii) care directed by up-front anorectal function testing. Model inputs were derived from systematic reviews of prospective clinical trials, national cost data sets, and observational cohort studies of the impact of chronic constipation on health outcomes, healthcare costs, and work productivity.

RESULTS: The most cost-effective strategy was upfront anorectal function testing to triage patients to appropriate therapy, in which the subset of patients without anal hypocontractility on anorectal manometry and with a balloon expulsion time of at least 6.5 seconds would be referred to PFPT. In sensitivity analysis, empiric PFPT was more cost effective than empiric prescription drugs except for situations in which the primary goal of treatment was to increase bowel movement frequency. If adopted, gastroenterologists would refer ∼17 patients per year to PFPT, supporting feasibility.

DISCUSSION: Anorectal function testing seems to be an emergent technology to optimize cost-effective outcomes, overcoming testing costs by phenotyping care.

Muftah M, Hartnett DA, Flanagan R, et al. Allergic phenotype identified on allergen testing is associated with proton pump inhibitor nonresponse in eosinophilic esophagitis. Journal of gastroenterology and hepatology. Published online 2024. doi:10.1111/jgh.16469

BACKGROUND AND AIM: Food/environmental allergens have been associated with eosinophilic esophagitis (EoE); however, the correlation between allergy profiles and disease responsiveness to proton pump inhibitor (PPI) therapy remains unclear. We aimed to assess the association between food/environmental allergies identified on allergen testing and histologic response to PPI in patients with treatment-naive EoE.

METHODS: Adults with newly diagnosed EoE who underwent formal testing for food/environmental allergies at a tertiary center were included. All patients underwent twice-daily PPI for 8 weeks with subsequent repeat endoscopy and biopsy to assess histologic response. Patients with <15 eosinophils/hpf on post-PPI mucosal biopsies were classified as responders (PPI-r-EoE), while those with ≥15 eosinophils/hpf were nonresponders (PPI-nr-EoE).

RESULTS: Sixty-one patients met inclusion criteria (21 PPI-r-EoE vs 40 PPI-nr-EoE). Demographic, clinical, and endoscopic finding variables were similar between groups. Positive food allergen test was more prevalent among PPI-nr-EoE patients (82.5% vs 42.9%, P = 0.003). On multivariable analysis, positive food allergen testing remained an independent predictor for PPI nonresponse (aOR 0.15, CI: 0.04-0.58, P = 0.0006). Positive environmental allergen testing was highly prevalent, with no significant differences between groups (77.5% vs 95.2%, P = 0.14). However, higher number of positive environmental allergens (23.3% [≥5 allergens] vs 73.3% [<5 allergens], P = 0.003) and specific aeroallergens correlated with PPI-nr-EoE.

CONCLUSION: Positive food allergy testing and increased environmental allergens predicted lower likelihood of histologic response to PPI in EoE. Our findings support an allergic phenotype of EoE that may less likely respond to PPI therapy. Formal allergen testing may play a role in therapy selection and tailored management in EoE.

Shah ED, Yadlapati R, Chan WW. Optimizing the Management Algorithm for Esophageal Dysphagia After Index Endoscopy: Cost-Effectiveness and Cost-Minimization Analysis. The American journal of gastroenterology. 2024;119(1):97-106. doi:10.14309/ajg.0000000000002521

INTRODUCTION: Guidelines advise esophageal motility testing for dysphagia when structural disorders are ruled out, but cost concerns impede adoption. We evaluated cost-effective positioning of esophageal motility testing in the algorithm to evaluate esophageal dysphagia.

METHODS: We developed a decision analytic model comparing 3 strategies: (i) esophageal manometry, (ii) screening impedance planimetry followed by esophageal manometry if needed, or (iii) nonalgorithmic usual care. Diagnostic test accuracy was adapted to expected rates of esophageal motility disorders in general gastroenterology populations. We modeled routine testing for all patients with nonstructural/mechanical dysphagia compared with selective testing with strong suspicion for achalasia. Cost outcomes were defined on national commercial and Medicare datasets stratified on age and sex. Health outcomes were modeled on populations with achalasia. The time horizon was 1 year.

RESULTS: Motility testing was preferred over nonalgorithmic usual care due to cost savings rather than health gains. To commercial insurers, routine esophageal manometry for nonstructural/mechanical dysphagia would be cost-saving below a reimbursed cost of $2,415. Screening impedance planimetry would be cost saving below a reimbursed cost of $1,130. The limit for reimbursed costs would be lower for patients older than 65 years to achieve cost savings mainly due to insurance. Sex did not significantly influence cost-effectiveness. Patients and insurers preferred routine screening impedance planimetry before manometry when the index of suspicion for achalasia was below 6%.

DISCUSSION: Aligning with practice guidelines, routine esophageal motility testing seems cost saving to patients and insurers compared with nonalgorithmic usual care to evaluate nonstructural/mechanical dysphagia. Choice of testing should be guided by index of suspicion.