Comparing Costs and Outcomes of Treatments for Irritable Bowel Syndrome With Diarrhea: Cost-Benefit Analysis

Evaluating Equity in Clinical Trial Accessibility: An Analysis of Demographic, Socioeconomic, and Educational Disparities in Irritable Bowel Syndrome Drug Trials

INTRODUCTION

Irritable bowel syndrome (IBS), a disorder of gut-brain interaction, imposes a significant economic burden because of its high prevalence and the chronic nature of its symptoms. IBS currently has 7 United States Food and Drug Administration-approved treatments. Despite efforts to improve diversity in randomized controlled trials' participation, significant disparities remain in various medical fields; yet, these have not been thoroughly examined within the context of IBS. We aimed to investigate the demographic, socioeconomic, educational, and geographic disparities in IBS drug trials.

METHODS

We conducted a systematic review of phase 3 randomized controlled trials on United States Food and Drug Administration-approved drugs for the treatment of IBS with constipation and IBS with diarrhea in the United States. Data on participant demographics and trial site locations were extracted and analyzed to identify disparities.

RESULTS

Our analysis included 17 studies encompassing 21 trials with 17,428 participants. Approximately 77.3% of participants were female, with a mean age of 45.4 years. Race was reported in 95% of the trials, but only 35% disclosed ethnicity. White participants constituted the majority at 79.3%. Hispanics accounted for only 5.9%. Counties without trial sites had smaller average population sizes compared with trial and trial-adjacent counties. Socioeconomic indicators such as poverty rates, median household income, educational attainment, and broadband internet access were lower in counties without trial sites, with higher average Area Deprivation Index scores indicating greater deprivation.

DISCUSSION

The findings highlight significant disparities in IBS trial participation across race, ethnicity, gender, and socioeconomic backgrounds. This raises potential concerns about generalizability of trial outcomes and underscores the need for strategies to enhance inclusivity in clinical research.

Economic Evaluations of Non-Pharmacological Interventions for Treating Disorders of Gut-Brain Interaction: A Scoping Review

BACKGROUND AND OBJECTIVES

Disorders of gut-brain interaction are highly prevalent and burdensome conditions for both patients and healthcare systems. Given the limited effectiveness of pharmacotherapy in treating disorders of gut-brain interaction, non-pharmacological interventions are increasingly used; however, the value for money of non-pharmacological treatments is uncertain. This is the first review to assess the economic evaluation evidence of non-pharmacological interventions for disorders of gut-brain interaction.

METHODS

A scoping review was conducted in line with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews (PRISMA-ScR) guidelines. Reporting adhered to ISPOR's good practices for systematic reviews with cost and cost-effectiveness outcomes. Comprehensive searches were performed on 24 October, 2023, and an updated search was run on 18 May, 2024 in PubMed/MEDLINE, Embase, Web of Science, Scopus and the International HTA database, with two reviewers screening studies in parallel. The novel Criteria for Health Economic Quality Evaluation (CHEQUE) framework was used to assess methodological and reporting quality. Reporting quality was further assessed using the Consolidated Health Economic Evaluation Reporting Standards (CHEERS) 2022.

RESULTS

Fifteen studies were included. Most studies examined treatments for irritable bowel syndrome. Cognitive behavioural therapy, dietary interventions and sacral neuromodulation were cost effective. Acupuncture and physiotherapy were not. CHEQUE assessment showed 12 studies met at least 70% of the methodological criteria, and 14 studies achieved 70% or more for reporting quality.

CONCLUSIONS

This review highlights gaps in the current evidence base, particularly in the robustness and generalisability of results due to methodological inconsistencies. Future research should incorporate longer follow-ups, comprehensive cost assessments, subgroup analyses, equity considerations and clearer justifications for modelling assumptions.

A Novel, IBS-Specific IgG ELISA-Based Elimination Diet in Irritable Bowel Syndrome: A Randomized, Sham-Controlled Trial

BACKGROUND & AIMS

Personalized dietary therapies for irritable bowel syndrome (IBS) are needed and an immunoglobulin (Ig)G-antibody-based elimination diet presents a potential solution. However, existing studies have serious methodological limitations. This study aimed to assess the efficacy of an elimination diet by using a novel IBS-specific IgG assay.

METHODS

We conducted a randomized, double-blind, sham-controlled trial enrolling subjects with IBS from 8 centers. Subjects positive for ≥1 food on an 18-food IgG assay and an average daily abdominal pain intensity score between 3.0 and 7.5 on an 11.0-point scale during a 2-week run-in period were randomized to either an experimental antibody-guided diet or sham diet for 8 weeks. The primary outcome was a ≥30% decrease in abdominal pain intensity for ≥2 of the last 4 weeks of the treatment period.

RESULTS

Among 238 randomized subjects with IBS, 223 were included in the modified intention-to-treat analysis. A significantly greater proportion of subjects in the experimental diet group met the primary outcome than those in the sham diet group (59.6% vs 42.1%, P = .02). Subgroup analysis revealed that a higher proportion of subjects with constipation-predominant IBS and IBS with mixed bowel habits in the experimental diet group met the primary endpoint vs the sham group (67.1% vs 35.8% and 66% vs 29.5%, respectively).

CONCLUSIONS

Subjects on an IgG-guided elimination diet were more likely to achieve the primary endpoint than those on a sham elimination diet. Subgroup analysis suggests a more robust benefit for subjects with constipation-predominant IBS and IBS with mixed bowel habits. This highlights the potential effectiveness of a personalized elimination diet based on a novel IBS-specific IgG assay. A larger study is warranted to validate these observations. (ClinicalTrials.gov, Number NCT03459482.).

Non-pharmaceutical treatments for irritable bowel syndrome

Irritable bowel syndrome (IBS) is a chronic disorder of gut-brain interaction that impacts a significant portion of the population and is associated with substantial morbidity, reduced quality of life, and economic impact globally. The pathophysiology of IBS is complex and incompletely understood, and the heterogeneity of IBS is reflected in the variety of pharmaceutical and non-pharmaceutical therapies utilized for the management of IBS. Given limitations with pharmaceutical treatments, many patients with IBS seek non-pharmaceutical options. Several non-pharmaceutical treatments such as the low FODMAP diet and brain-gut behavior interventions such as gut directed hypnosis and cognitive behavioral therapy are now considered standard of care and are part of all major guidelines for the treatment of IBS. However, challenges with access to and optimal implementation of these therapies remain. This review focuses on the current evidence for common non-pharmaceutical treatments for IBS, including the latest advances in dietary and brain-gut behavioral care, in addition other complementary and integrative health practices and emerging therapies.

Results from a Cross-Sectional Observational Study Examining Irritable Bowel Syndrome Patients Six Months After Finishing Their Participation in the ViIBS Trial

BACKGROUND/OBJECTIVES

A recent clinical (ViIBS) trial investigating the effects of a balanced multi-strain synbiotic in irritable bowel syndrome (IBS) patients showed that twelve weeks of treatment resulted in significant improvements across all major IBS symptoms. The current observational study pursued three aims: investigate patients' attitude towards the intake of pro- or synbiotics during the six months after finishing their trial participation, determine the severity of IBS symptoms, and assess IBS diagnosis scores.

METHODS

During a single six-month follow-up examination, patients were asked about the intake of probiotics or synbiotics. For the study, former placebo-group patients who abstained from taking probiotics were compared with synbiotic-group patients who continued taking the tested synbiotic. IBS symptom severity was assessed with the IBS-Severity of Symptoms Scale and the IBS diagnosis score with the IBS questionnaire of the World Gastroenterology Organisation.

RESULTS

The control group comprised 17 patients (out of 70 from the placebo group participating in the follow-up) and the treatment group 75 (out of 91 examined). IBS symptom severity was significantly lower in the treatment group (23.5 ± 33.1) than in the placebo group (232.6 ± 35.1). IBS diagnosis scores were 5.9 ± 2.5 and 21.2 ± 2.0 in the treatment and control group, respectively.

CONCLUSIONS

Measurement values for the treatment group indicate the absence of IBS. The results indicate that the prolonged administration of the balanced multi-strain synbiotic can potentially reduce IBS symptom severity and IBS diagnosis scores to levels indicating the absence of IBS, an observation to be followed up in a controlled clinical trial.

Algorithms or biomarkers in patients with lower DGBI?

BACKGROUND

Several organizations have proposed guidelines or clinical decision tools for the management of patients with disorders of gut-brain interactions (DGBI) affecting the lower digestive tract including irritable bowel syndrome and chronic idiopathic constipation. Such algorithms are based on sequential therapeutic trials and modifying the treatment strategy based on efficacy and adverse events.

PURPOSE

The aims of this review are to evaluate the evidence for efficacy of second- and third-line pharmacotherapies and to assess the evidence for the alternative option to manage subgroups of patients with symptoms suggestive of lower DGBI based on diagnostic tests or documented dysfunctions. The preeminent tests to identify such subgroups that present with symptoms that overlap with lower DGBI are detailed: digital rectal examination as well as anorectal manometry and balloon expulsion for evacuation disorders, detailed measurements of colonic transit, and diagnosis of bile acid diarrhea or carbohydrate malabsorption based on biochemical measurements. The review also addresses the cost implications of screening to exclude alternative diagnoses and the costs of therapy associated with the therapeutic options following an algorithmic approach to treatment from the perspective of society, insurer, or patient. Finally, the costs of the diagnostic tests to identify actionable biomarkers and the evidence of efficacy of individualized therapy based on formal diagnosis or documentation of abnormal functions are detailed in the review.

Optimizing the Management Algorithm for Heartburn in General Gastroenterology: Cost-Effectiveness and Cost-Minimization Analysis

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.

Synbiotics as Treatment for Irritable Bowel Syndrome: A Review

Irritable bowel syndrome is a persistent disturbance of the function of the gastrointestinal tract with a prevalence of about 11.2% in the population at large. While the etiology of the disorder remains unclear, there is mounting evidence that the disturbance of the gut microbiota is at least one contributing factor. This insight resulted in clinical trials investigating the therapeutic effects of products containing probiotic microorganisms. Most studies with IBS patients have evaluated the therapeutic effects of mono- and multi-strain probiotics, but only a few studies have investigated the efficacy of synbiotics (combinations of probiotic bacteria and one or more prebiotic components). This review summarizes the results from eight randomized, placebo-controlled clinical trials that investigated the efficacy of synbiotic preparations (three mono-strain and five multi-strain products) in adult IBS patients. While data remain sparse, some of the surveyed clinical trials have demonstrated interesting efficacy results in IBS patients. To allow a judgment of the role played by synbiotics in the treatment of IBS patients, more high-quality clinical trials are needed.

Effectiveness of a Balanced Nine-Strain Synbiotic in Primary-Care Irritable Bowel Syndrome Patients-A Multi-Center, Randomized, Double-Blind, Placebo-Controlled Trial

The aim of the study was to characterize effects of a multi-strain synbiotic in patients with moderate to severe irritable bowel syndrome (IBS) of all stool form types. A total of 202 adult IBS patients were randomized (1:1) and after a four-week treatment-free run-in phase and were treated either with the synbiotic or a placebo for 12 weeks. The primary endpoints were the assessment of the severity of IBS symptoms (IBS-SSS) and the improvement of IBS global symptoms (IBS-GIS). Secondary endpoints comprised adequate relief (IBS-AR scale), stool form type (Bristol Stool Form Scale), bowel movements, severity of abdominal pain and bloating, stool pressure, feeling of incomplete stool evacuation, and adverse events. A total of 201 patients completed the study. Synbiotic treatment, in comparison to placebo, significantly improved IBS-SSS and IBS-GIS scores. At the end of the treatment, 70% of patients in the synbiotic group achieved adequate relief. After 12 weeks of treatment, the secondary endpoints were favorably differentiated in the synbiotic group when compared with the placebo group. Two patients in the synbiotic group reported transient adverse events (headache). The results indicate that treatment of IBS patients with the synbiotic significantly improved all major symptoms of IBS and was well-tolerated. The ClinicalTrials.gov registration was NCT05731232.

The function of the gut microbiota-bile acid-TGR5 axis in diarrhea-predominant irritable bowel syndrome

Imbalanced gut microbiota (GM) and abnormal fecal bile acid (BA) are thought to be the key factors for diarrhea-predominant irritable bowel syndrome (IBS-D), but the underlying mechanism remains unclear. Herein, we explore the influence of the GM-BA-Takeda G-protein-coupled receptor 5 (TGR5) axis on IBS-D. Twenty-five IBS-D patients and fifteen healthy controls were recruited to perform BA-related metabolic and metagenomic analyses. Further, the microbiota-humanized IBS-D rat model was established by fecal microbial transplantation (FMT) to investigate the GM-BA-TGR5 axis effects on the colonic barrier and visceral hypersensitivity (VH) in IBS-D. Finally, we used chenodeoxycholic acid (CDCA), an important BA screened out by metabolome, to evaluate whether it affected diarrhea and VH via the TGR5 pathway. Clinical research showed that GM associated with bile salt hydrolase (BSH) activity such as Bacteroides ovatus was markedly reduced in the GM of IBS-D, accompanied by elevated total and primary BA levels. Moreover, we found that CDCA not only was increased as the most important primary BA in IBS-D patients but also could induce VH through upregulating TGR5 in the colon and ileum of normal rats. TGR5 inhibitor could reverse the phenotype, depression-like behaviors, pathological change, and level of fecal BSH in a microbiota-humanized IBS-D rat model. Our findings proved that human-associated FMT could successfully induce the IBS-D rat model, and the imbalanced GM-BA-TGR5 axis may promote colonic mucosal barrier dysfunction and enhance VH in IBS-D.

IMPORTANCE

Visceral hypersensitivity and intestinal mucosal barrier damage are important factors that cause abnormal brain-gut interaction in diarrhea-predominant irritable bowel syndrome (IBS-D). Recently, it was found that the imbalance of the gut microbiota-bile acid axis is closely related to them. Therefore, understanding the structure and function of the gut microbiota and bile acids and the underlying mechanisms by which they shape visceral hypersensitivity and mucosal barrier damage in IBS-D is critical. An examination of intestinal feces from IBS-D patients revealed that alterations in gut microbiota and bile acid metabolism underlie IBS-D and symptom onset. We also expanded beyond existing knowledge of well-studied gut microbiota and bile acid and found that Bacteroides ovatus and chenodeoxycholic acid may be potential bacteria and bile acid involved in the pathogenesis of IBS-D. Moreover, our data integration reveals the influence of the microbiota-bile acid-TGR5 axis on barrier function and visceral hypersensitivity.

Differences in provider recommendations for Black/African American and White patients with irritable bowel syndrome

BACKGROUND

Health disparities and barriers to equitable care for patients from racial and ethnic minority backgrounds are common. We sought to evaluate disparities in management recommendations among Black/African American (AA) patients seeking care for IBS.

METHODS

We assembled a retrospective cohort of patients at two tertiary care centers who were self-identifying as Black/AA and attended a first gastroenterology consult for IBS. These patients were age- and sex-matched to White controls with IBS also attending an initial gastroenterology consult. Retrospective chart review determined patient demographics, income, comorbidities, as well as provider management recommendations including pharmacologic therapies and non-pharmacologic interventions.

KEY RESULTS

Among 602 IBS patients ages 14-88 (M ± SD = 43.6 ± 18.6 years) with IBS, those who identified as Black/AA (n = 301) had a lower estimated mean income and were significantly more likely to have a number of specific chronic medical conditions. Black/AA patients were significantly less likely to have implemented dietary changes for symptoms prior to receiving a diagnosis of IBS from a gastroenterologist. Black/AA patients were also less likely to receive a referral to a dietician within 1 year following their diagnosis of IBS (p = 0.01). Black/AA patients were prescribed pharmacologic therapy more often for constipation (41.9% vs. 34.6%, p = 0.01). It was more common for White patients to present at the initial encounter having already initiated a neuromodulator (41.9% vs. 27.9%, p < 0.001).

CONCLUSION & INFERENCES

Management recommendations for IBS appear to vary by race, specifically for dietary advice and referrals.

Abnormal gastrointestinal motility is a major factor in explaining symptoms and a potential therapeutic target in patients with disorders of gut-brain interaction

The objective of this article is to review the evidence of abnormal gastrointestinal (GI) tract motor functions in the context of disorders of gut-brain interaction (DGBI). These include abnormalities of oesophageal motility, gastric emptying, gastric accommodation, colonic transit, colonic motility, colonic volume and rectal evacuation. For each section regarding GI motor dysfunction, the article describes the preferred methods and the documented motor dysfunctions in DGBI based on those methods. The predominantly non-invasive measurements of gut motility as well as therapeutic interventions directed to abnormalities of motility suggest that such measurements are to be considered in patients with DGBI not responding to first-line approaches to behavioural or empirical dietary or pharmacological treatment.

Antibiotics and Probiotics for Irritable Bowel Syndrome

Irritable bowel syndrome (IBS) is a disorder of a gut-brain interaction characterised by abdominal pain and a change in stool form or frequency. Current symptom-based definitions and the classification of IBS promote heterogeneity amongst patients, meaning that there may be several different pathophysiological abnormalities leading to similar symptoms. Although our understanding of IBS is incomplete, there are several indicators that the microbiome may be involved in a subset of patients. Techniques including a faecal sample analysis, colonic biopsies, duodenal aspirates or surrogate markers, such as breath testing, have been used to examine the gut microbiota in individuals with IBS. Because of a lack of a clear definition of what constitutes a healthy gut microbiota, and the fact that alterations in gut microbiota have only been shown to be associated with IBS, a causal relationship is yet to be established. We discuss several hypotheses as to how dysbiosis may be responsible for IBS symptoms, as well as potential treatment strategies. We review the current evidence for the use of antibiotics and probiotics to alter the microbiome in an attempt to improve IBS symptoms. Rifaximin, a non-absorbable antibiotic, is the most studied antibiotic and has now been licensed for use in IBS with diarrhoea in the USA, but the drug remains unavailable in many countries for this indication. Current evidence also suggests that certain probiotics, including Lactobacillus plantarum DSM 9843 and Bifidobacterium bifidum MIMBb75, may be efficacious in some patients with IBS. Finally, we describe the future challenges facing us in our attempt to modulate the microbiome to treat IBS.

Current evidence for dietary therapies in irritable bowel syndrome

PURPOSE OF REVIEW

Diet appears to trigger symptoms in the majority of individuals with irritable bowel syndrome (IBS) and is associated with a reduced quality of life. There has been a recent focus on the role of dietary therapies to manage individuals with IBS. The aim of this review is to discuss the utility of traditional dietary advice (TDA), low-FODMAP diet (LFD) and gluten-free diet (GFD) in IBS.

RECENT FINDINGS

Several recent randomized controlled trials (RCTs) have been published demonstrating the efficacy of the LFD and GFD in IBS, with the evidence base for TDA being predominantly based on clinical experience, with emerging RCTs evaluating TDA. Only one RCT has been published to date comparing TDA, LFD and GFD head to head, with no difference noted between diets in terms of efficacy. However, TDA has been noted to be more patient-friendly and is commonly implemented as a first-line dietary therapy.

SUMMARY

Dietary therapies have been demonstrated to improve symptoms in patients with IBS. In view of insufficient evidence to recommend one diet over another currently, specialist dietetic input in conjunction with patient preference is required to determine implementation of dietary therapies. Novel methods of dietetic delivery are required in view of the lack of dietetic provision to deliver these therapies.

Efficacy and Acceptability of Dietary Therapies in Non-Constipated Irritable Bowel Syndrome: A Randomized Trial of Traditional Dietary Advice, the Low FODMAP Diet, and the Gluten-Free Diet

BACKGROUND & AIMS

Various diets are proposed as first-line therapies for non-constipated irritable bowel syndrome (IBS) despite insufficient or low-quality evidence. We performed a randomized trial comparing traditional dietary advice (TDA) against the low FODMAP diet (LFD) and gluten-free diet (GFD).

METHODS

Patients with Rome IV-defined non-constipated IBS were randomized to TDA, LFD, or GFD (the latter allowing for minute gluten cross-contamination). The primary end point was clinical response after 4 weeks of dietary intervention, as defined by ≥50-point reduction in IBS symptom severity score (IBS-SSS). Secondary end points included (1) changes in individual IBS-SSS items within clinical responders, (2) acceptability and food-related quality of life with dietary therapy, (3) changes in nutritional intake, (4) alterations in stool dysbiosis index, and (5) baseline factors associated with clinical response.

RESULTS

The primary end point of ≥50-point reduction in IBS-SSS was met by 42% (n = 14/33) undertaking TDA, 55% (n = 18/33) for LFD, and 58% (n = 19/33) for GFD (P = .43). Responders had similar improvements in IBS-SSS items regardless of their allocated diet. Individuals found TDA cheaper (P < .01), less time-consuming to shop (P < .01), and easier to follow when eating out (P = .03) than the GFD and LFD. TDA was also easier to incorporate into daily life than the LFD (P = .02). Overall reductions in micronutrient and macronutrient intake did not significantly differ across the diets. However, the LFD group had the greatest reduction in total FODMAP content (27.7 g/day before intervention to 7.6 g/day at week 4) compared with the GFD (27.4 g/day to 22.4 g/day) and TDA (24.9 g/day to 15.2 g/day) (P < .01). Alterations in stool dysbiosis index were similar across the diets, with 22%-29% showing reduced dysbiosis, 35%-39% no change, and 35%-40% increased dysbiosis (P = .99). Baseline clinical characteristics and stool dysbiosis index did not predict response to dietary therapy.

CONCLUSIONS

TDA, LFD, and GFD are effective approaches in non-constipated IBS, but TDA is the most patient-friendly in terms of cost and convenience. We recommend TDA as the first-choice dietary therapy in non-constipated IBS, with LFD and GFD reserved according to specific patient preferences and specialist dietetic input.

CLINICALTRIALS

gov: NCT04072991.

Impact of Rome IV irritable bowel syndrome on work and activities of daily living

BACKGROUND

Few studies have demonstrated the impact of irritable bowel syndrome (IBS) on work and activities of daily living.

METHODS

We collected demographic, gastrointestinal symptom, psychological health and quality of life data from 752 adults with Rome IV-defined IBS. We used the work productivity and activity impairment questionnaire for irritable bowel syndrome and the work and social adjustment scale to examine the degree of both impairment at work and in activities of daily living, as well as factors associated with these.

RESULTS

Of 467 individuals who were employed, 133 (28.5%) reported absenteeism, 373 (85.6%) presenteeism and 382 (81.8%) overall work impairment. A mean of 1.97 hours of work per week was lost due to IBS. Extrapolating this across the entire UK, we estimate that between 72 and 188 million hours of work are lost per year due to IBS in individuals of working age. Among all 752 participants, 684 (91.0%) reported any activity impairment with 220 (29.3%) reporting impairment in home management, 423 (56.3%) in social leisure activities, 207 (27.5%) in private leisure activities, and 203 (27.0%) in maintaining close relationships. Severe IBS, higher levels of anxiety, depression, somatization and gastrointestinal symptom-specific anxiety, and lower levels of IBS-related quality of life were associated with impairment in both work and activities of daily living.

CONCLUSION

Patients with IBS experience a substantial impact on their work and activities of daily living because of their IBS. Future studies should assess the impact of medical interventions on the ability to work and participate in social activities.

Price Is Right: Exploring Prescription Drug Coverage Barriers for Irritable Bowel Syndrome Using Threshold Pricing Analysis

BACKGROUND

Prescription drug costs exert profound effects on commercial insurance coverage and access to effective therapy.

AIMS

We aimed to assess threshold pricing to achieve budget neutrality of FDA-approved drugs treating irritable bowel syndrome from an insurance perspective, based on cost-savings resulting in decreased healthcare utilization through effective disease management.

METHODS

We constructed a decision-analytic model from an insurance perspective to assess the budget impact of IBS prescription drugs under usual insurance coverage levels in practice: (1) unrestricted drug access or (2) step therapy in a primary care population of middle-age, care-seeking IBS patients. Budget-neutral drug prices were then calculated which resulted in $0 budget impact to insurers with a short-term, one-year time horizon.

RESULTS

If used according to FDA labeling, IBS-D drugs cost between $4778 and $16,844 per year and IBS-C drugs cost between $4319 and $4955 per year. These drug costs often exceed insurance expenditures of $6999 for IBS-D and $3929 for IBS-C if left untreated. Therefore, for drugs to have $0 budget impact to insurers, their prices would need to be discounted 36.7-74.2% for IBS-D drugs and 59.3-82.5% for IBS-C. IBS drugs are already priced to support step therapy "failing one of several common, inexpensive IBS treatments with a responder rate > 30-40%," reflecting the subpopulation with more severe disease and greater healthcare costs.

CONCLUSIONS

Broader prescription drug coverage for patients failing common, inexpensive IBS treatments to which at least 30-40% of patients would typically respond appears warranted to enable gastroenterologists to offer personalized approaches targeting specific mechanisms of this heterogeneous disease.

Evaluating the Impact of Cost on the Treatment Algorithm for Chronic Idiopathic Constipation: Cost-Effectiveness Analysis

INTRODUCTION

Chronic idiopathic constipation (CIC) is a common and burdensome illness. We performed a cost-effectiveness analysis of the US Food and Drug Administration-approved CIC drugs to evaluate and quantify treatment preferences compared with usual care from insurer and patient perspectives.

METHODS

We evaluated the subset of patients with CIC and documented failure of over-the-counter (OTC) osmotic or bulk-forming laxatives. A RAND/UCLA consensus panel of 8 neurogastroenterologists informed model design. Treatment outcomes and costs were defined using integrated analyses of registered clinical trials and the US Centers for Medicare and Medicaid Services-supported cost databases. Quality-adjusted life years (QALYs) were calculated using health utilities derived from clinical trials. A 12-week time horizon was used.

RESULTS

With continued OTC laxatives, CIC-related costs were $569 from an insurer perspective compared with $3,154 from a patient perspective (considering lost wages and out-of-pocket expenses). CIC prescription drugs increased insurer costs by $618-$1,015 but decreased patient costs by $327-$1,117. Effectiveness of CIC drugs was similar (0.02 QALY gained/12 weeks or ∼7 healthy days gained/year). From an insurer perspective, prescription drugs (linaclotide, prucalopride, and plecanatide) seemed less cost-effective than continued OTC laxatives (incremental cost-effectiveness ratio >$150,000/QALY gained). From a patient perspective, the cost-effective algorithm started with plecanatide, followed by choosing between prucalopride and linaclotide starting at the 145-μg dose (favoring prucalopride among patients whose disease affects their work productivity). The patient perspective was driven by drug tolerability and treatment effects on quality of life.

DISCUSSION

Addressing costs at a policy level has the potential to enable patients and clinicians to move from navigating barriers in treatment access toward truly optimizing treatment choice.

The estimation of a preference-based single index for the IBS-QoL by mapping to the EQ-5D-5L in patients with irritable bowel syndrome

Purpose

The Irritable Bowel Syndrome Quality of Life (IBS-QoL) questionnaire is a commonly used and validated IBS-specific QoL instrument. However, this questionnaire is in contrast to the EQ-5D-5L, not preference-based and as such does not allow calculation of QALYs. The objective of this study was to describe the convergent- and known-group validity of both questionnaires and to develop a mapping algorithm from EQ-5D-5L which enable IBS-QoL scores to be transformed into utility scores for use in economic evaluations.

Methods

We used data from two multicenter randomized clinical trials, which represented the estimation and external validation dataset. The convergent validity was investigated by examining correlations between the EQ-5D-5L and IBS-QoL and the known-group validity by calculating effect sizes. Ordinary least squares (OLS), censored least absolute deviations (CLAD), and mixture models were used in this mapping approach.

Results

283 IBS patients were included (n = 189 vs. n = 84). Mean IBS-QoL score was 71.13 (SD 15.66) and mean EQ-5D-5L utility score was 0.73 (SD 0.19). The overall sensitivity of the IBS-QoL and EQ-5D-5L to discriminate between patient and disease characteristics was similar. CLAD model 4, containing the total IBS-QoL score and squared IBS-SSS (IBS severity scoring system), was chosen as the most appropriate model to transform IBS-QoL scores into EQ-5D-5L utility scores.

Conclusion

This study reports the development of an algorithm where the condition-specific questionnaire IBS-QoL can be used to calculate utility values for use in economic evaluations. Including a clinical measure, IBS-SSS, in the model improved the performance of the algorithm.

Supplementary Information

The online version contains supplementary material available at 10.1007/s11136-021-02995-y.

Pharmacologic, Dietary, and Psychological Treatments for Irritable Bowel Syndrome With Constipation: Cost Utility Analysis

Introduction. Irritable bowel syndrome (IBS) is the most common gastroenterology referral and one of the most common gastrointestinal complaints in primary care. We performed a cost-utility analysis of the most common treatments available in general practice for IBS with constipation (IBS-C), the most expensive IBS subtype. Methods. We developed a decision analytic model evaluating guideline-recommended and Food and Drug Administration-approved drugs, supplements, and dietary/psychological interventions. Model inputs were derived from "global symptom improvement" outcomes in systematic reviews of clinical trials. Costs were derived from national datasets. Analysis was performed with a 1-year time horizon from patient and payer perspectives. We analyzed a prototypical managed-care health plan with no cost-sharing to the patient. Results. From a payer perspective, global IBS treatments (including low FODMAP, cognitive behavioral therapy [CBT], neuromodulators), which are not specific to the IBS-C bowel subtype were less expensive than on-label prescription drug treatments. From a patient perspective, on-label prescription drug treatment with linaclotide was the least expensive treatment strategy. Drug prices and costs to manage untreated IBS-C were most important determinants of payer treatment preferences. Effects of treatment on missed work-days and need for repeated appointments to complete treatment were the most important determinants of treatment preference to patients. Discussion. Due mostly to prescription drug prices, neuromodulators, low FODMAP, and CBT appear cost-effective compared to on-label drug treatments from a payer perspective in cost-utility analysis. These findings may explain common treatment barriers in clinical practice.