Development of a Symptom-Focused Patient-Reported Outcome Measure for Functional Dyspepsia: The Functional Dyspepsia Symptom Diary (FDSD)

Patient-Reported Outcomes in Disorders of Gut-Brain Interaction

Disorders of gut-brain interaction are characterized by chronic gastrointestinal symptoms in the absence of abnormal endoscopic or radiologic findings or objective biomarkers that can be identified during routine clinical evaluation. The assessment of the symptom pattern and severity, therefore, is the key modality to evaluate the presence, impact, and evolution of these conditions, for both clinical and regulatory purposes. Patient-reported outcomes are structured symptom assessment questionnaires designed to evaluate symptom patterns, quantify severity of symptoms, and evaluate response to treatment at follow-up. This review provides an overview of currently available patient-reported outcomes for evaluating the main disorders of gut-brain interaction, specifically, functional dyspepsia; irritable bowel syndrome; and chronic constipation. It summarizes their content, level of validation for clinical practice and for research, and the regulatory approach to these conditions. Expected future developments and need for further research on patient-reported outcomes for these and other disorders of gut-brain interaction are highlighted.

Transcutaneous Auricular Vagal Nerve Stimulation Is Effective for the Treatment of Functional Dyspepsia: A Multicenter, Randomized Controlled Study

INTRODUCTION

Vagal nerve stimulation (VNS) can be used to modulate gastrointestinal motility, inflammation, and nociception. However, it remains unclear whether VNS is effective in adult patients with functional dyspepsia (FD). We investigated the effectiveness of transcutaneous auricular VNS (taVNS) in patients with FD.

METHODS

Consecutive patients with FD meeting Rome IV criteria with modified FD Symptom Diary score ≥10 were enrolled. Patients were randomly allocated to 10-Hz taVNS (V10 group), 25-Hz taVNS (V25 group), or sham group, with 30 minutes of treatment twice a day for 4 weeks. The primary outcome was the response rate at week 4, defined as the proportion of patients whose modified FD Symptom Diary score was reduced ≥5 when compared with the baseline. Secondary outcomes included adequate relief rate and adverse events.

RESULTS

A total of 300 patients were randomized to V10 (n = 101), V25 (n = 99), and sham groups (n = 100). After 4 weeks of treatment, V10 and V25 groups had a higher response rate (81.2% vs 75.9% vs 47%, both P < 0.001) and adequate relief rate (85.1% vs 80.8% vs 67%, both P < 0.05) compared with the sham group. There was no significant difference between V10 and V25 in response rate and adequate relief rate (both P > 0.05). The efficacy of taVNS (both 10 and 25 Hz) lasted at week 8 and week 12 during follow-up period. Adverse events were all mild and comparable among the 3 groups (1%-3%).

DISCUSSION

Our study firstly showed that 4-week taVNS (both 10 and 25 Hz) was effective and safe for the treatment of adult FD ( clinicaltrials.gov number: NCT04668534).

Patient-reported outcome measures in functional dyspepsia: a systematic review and COSMIN analysis

BACKGROUND

Functional dyspepsia (FD) as a type of disorders of brain-gut interaction (DBGI), patient self-reporting of its symptoms becomes an important component of clinical outcome assessment. We performed a systematic review using Consensus Based Standards for the Selection of Health Measurement Instruments (COSMIN) guidelines to identify the best available patient-reported outcome measure (PROM) of FD.

METHODS

The study was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). We searched four databases with no date limit, looking for previously confirmed PROMs for evaluating FD symptoms. An overall rating was then assigned based upon COSMIN guidelines, and the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach was used to assess the level of evidence for psychometric properties of included PROMs.

RESULTS

Thirty articles covering outcome indicators of 24 patient reports were included. The Leuven Postprandial Distress Scale (LPDS) showed adequate content validity and moderate quality evidence of adequate internal consistency to generate an A recommendation.

CONCLUSION

LPDS is currently the most recommended PROM for patient self-reported FD symptoms. However, it fails to assess two important areas of cross-cultural validity/ measurement invariance and measurement error. Future research can be continuously improved on this basis.

Placebo response in pharmacological trials in patients with functional dyspepsia-A systematic review and meta-analysis

BACKGROUND

Pharmacological trials in functional dyspepsia (FD) are associated with high placebo response rates. We aimed to identify the magnitude and contributing factors to the placebo response.

METHODS

We conducted a systematic review and meta-analysis including randomized controlled trials (RCTs) with a dichotomous outcome in adult patients with FD that compared an active pharmacotherapeutic treatment with placebo. Our main outcome was identification of the magnitude of the pooled placebo response rate for the following endpoints: symptom responder, symptom-free responder, adequate relief responder, and combined endpoint responder (i.e., the primary endpoint of each specific trial regarding treatment response). Several putative moderators (i.e., patient, disease, and trial characteristics) were examined.

KEY RESULTS

We included 26 RCTs in our analysis. The pooled placebo response rate was 39.6% (95% CI 30.1-50.0) using the symptom responder definition, 20.5% (12.8-31.0) using the symptom-free responder definition, 38.5% (33.8-43.6) using the adequate relief responder definition, and 35.5% (31.6-39.7) using the combined endpoint responder definition. A lower overall baseline symptom score was significantly associated with a higher placebo response rate. No other moderators were found to significantly impact the placebo response rate. Due to the lack of data, no analyses could be performed according to individual FD subtypes or symptoms.

CONCLUSIONS AND INFERENCES

The pooled placebo response rate in pharmacological trials in FD is about 39%, depending on which responder definitions is used. Future trials should consider applying an entry criterion based on minimal level of symptom severity to decrease the placebo response. We also suggest separate reporting of core FD symptoms pending more concrete harmonization efforts in FD trials.

British Society of Gastroenterology guidelines on the management of functional dyspepsia

Functional dyspepsia (FD) is a common disorder of gut-brain interaction, affecting approximately 7% of individuals in the community, with most patients managed in primary care. The last British Society of Gastroenterology (BSG) guideline for the management of dyspepsia was published in 1996. In the interim, substantial advances have been made in understanding the complex pathophysiology of FD, and there has been a considerable amount of new evidence published concerning its diagnosis and classification, with the advent of the Rome IV criteria, and management. The primary aim of this guideline, commissioned by the BSG, is to review and summarise the current evidence to inform and guide clinical practice, by providing a practical framework for evidence-based diagnosis and treatment of patients. The approach to investigating the patient presenting with dyspepsia is discussed, and efficacy of drugs in FD summarised based on evidence derived from a comprehensive search of the medical literature, which was used to inform an update of a series of pairwise and network meta-analyses. Specific recommendations have been made according to the Grading of Recommendations Assessment, Development and Evaluation system. These provide both the strength of the recommendations and the overall quality of evidence. Finally, in this guideline, we consider novel treatments that are in development, as well as highlighting areas of unmet need and priorities for future research.

Cannabidiol for Functional Dyspepsia With Normal Gastric Emptying: A Randomized Controlled Trial

INTRODUCTION

Cannabidiol (CBD), a CBR2 agonist with limited psychic effects, antagonizes CB1/CB2 receptors. Allelic variation CNR1 (gene for CBR1) rs806378 and FAAH rs324420 were associated with altered gut motility and sensation. This study aimed to compare the pharmacodynamics and clinical effects of a 4-week treatment with pharmaceutical-grade CBD vs placebo and assess the interactions of FAAH and CNR1 gene variants on the effects of CBD in patients with functional dyspepsia (FD).

METHODS

We performed a randomized, double-blinded, placebo-controlled (1:1 ratio) study of CBD b.i.d. (20 mg/kg/d according to the US Food and Drug Administration escalation guidance) in FD patients with nondelayed gastric emptying (GE) at baseline. Symptoms were assessed by validated daily symptom diary (0-4 scale for upper abdominal pain, nausea, and bloating), weekly assessment of adequate relief, Leuven Postprandial Distress Scale (8 symptoms, adjectival scores rated 0-4 for severity), and quality of life (Short-Form Nepean Dyspepsia Index [average of 10 dimensions each on a 5-point scale]). After the 4-week treatment, all patients underwent measurements of GE of solids, gastric volumes, and Ensure nutrient satiation test. Statistical analysis compared 2 treatments for all endpoints and the effects of CBD in association with FAAH rs324420 and CNR1 rs806378.

RESULTS

CBD and placebo effects on physiological functions and patient response outcomes were not significantly different. There were borderline CBD treatment-by-genotype interactions: rs806378 CNR1 with Leuven Postprandial Distress Scale ( P = 0.06) and GE solids ( P = 0.12).

DISCUSSION

Approved doses of CBD used off-label do not relieve FD with normal baseline GE of solids or alter gastric motor functions and satiation. CBD treatment-by-gene interactions suggest potential benefits for postprandial distress with CNR1 rs806378 T allele.

Functional dyspepsia symptom diary is correlated with other questionnaires and associated with severity in patients with functional dyspepsia: a multicenter, prospective observational study

BACKGROUND AND AIM

Functional dyspepsia symptom diary (FDSD) is a newly designed questionnaire of functional dyspepsia (FD). The relationships between FDSD and other FD-related questionnaires and patient-reported severity remain unclear. This study aims to investigate the correlations between FDSD and other questionnaires and to determine the relationships between FDSD and FD severity.

METHODS

Consecutive outpatients with FD were prospectively enrolled in four tertiary hospitals. All patients were evaluated by six FD-related questionnaires, including FDSD, Dyspepsia Symptom Severity Index (DSSI), Gastrointestinal Symptom Rating Scale, Short-Form Nepean Dyspepsia Index, and Hamilton Depression and Anxiety Scale (HAMD and HAMA). The severity of FD was also graded as mild, moderate, and severe by patients themselves. Correlations between different scores were assessed by Spearman correlation coefficient (ρ), and risk factors for patient-reported severity were identified.

RESULTS

For 512 enrolled FD patients, the overall median FDSD score was 19 (2-42). FDSD was well correlated with DSSI (ρ = 0.64) and fairly correlated with the other four scores (ρ = 0.32-0.55) (all P < 0.001). Mild, moderate, and severe FD were reported by 18.5%, 55.9%, and 25.6% of patients, respectively. There were seven factors associated with the severe FD, including education level, duration, and subtypes of FD, prior treatment, FDSD, HAMD, and HAMA scores (all P < 0.10). FDSD ≥ 20 (odds ratio [OR] 3.3, 95% confidence interval [CI]: 2.0-5.2, P < 0.001) and HAMD ≥ 13 (OR 2.9, 95% CI: 1.8-4.6, P < 0.001) were independently associated with patient-reported severe FD.

CONCLUSIONS

This study firstly revealed that the newly developed FDSD correlated with other FD-related questionnaires. FDSD ≥ 20 and HAMD ≥ 13 were independently associated with severe FD reported by patients (clinicaltrials.gov number: NCT04953975).

Digital Instruments for Reporting of Gastrointestinal Symptoms in Clinical Trials: Comparison of End-of-Day Diaries Versus the Experience Sampling Method

Background

Questionnaires are necessary tools for assessing symptoms of disorders of the brain-gut interaction in clinical trials. We previously reported on the excellent adherence to a smartphone app used as symptom diary in a randomized clinical trial on irritable bowel syndrome (IBS). Other sampling methods, such as the experience sampling method (ESM), are better equipped to measure symptom variability over time and provide useful information regarding possible symptom triggers, and they are free of ecological and recall bias. The high frequency of measurements, however, could limit the feasibility of ESM in clinical trials.

Objective

This study aimed to compare the adherence rates of a smartphone-based end-of-day diary and ESM for symptom assessment in IBS and functional dyspepsia (FD).

Methods

Data from 4 separate studies were included. Patients with IBS participated in a randomized controlled trial, which involved a smartphone end-of-day diary for a 2+8-week (pretreatment + treatment) period, and an observational study in which patients completed ESM assessments using a smartphone app for 1 week. Patients with FD participated in a randomized controlled trial, which involved a smartphone end-of-day diary for a 2+12-week (pretreatment + treatment) period, and an observational study in which patients completed ESM assessments using a smartphone app for 1 week. Adherence rates were compared between these 2 symptom sampling methods.

Results

In total, 25 patients with IBS and 15 patients with FD were included. Overall adherence rates for the end-of-day diaries were significantly higher than those for ESM (IBS: 92.7% vs 69.8%, FD: 90.1% vs 61.4%, respectively).

Conclusions

This study demonstrates excellent adherence rates for smartphone app–based end-of-day diaries as used in 2 separate clinical trials. Overall adherence rates for ESM were significantly lower, rendering it more suitable for intermittent sampling periods rather than continuous sampling during longer clinical trials.

History-taking, Clinical Signs, Tests and Scores for Detection of Non-organic Dyspepsia (NOD) Among Patients With Acute Abdominal Pain (AAP)

BACKGROUND/AIM

The diagnostic accuracy of history-taking, clinical signs and tests and diagnostic scores (DSs) for patients with non-organic dyspepsia (NOD) have been rarely evaluated.

PATIENTS AND METHODS

A cohort of 1333 patients presenting with acute abdominal pain (AAP) were studied, including 50 patients with confirmed NOD. The most significant diagnostic variables (in multivariate logistic regression analysis) were used to construct six different DS models and their diagnostic accuracy was compared with clinical symptoms and signs and tests. Meta-analytical techniques were used to detect the summary sensitivity (Se) and specificity (Sp) estimates for each data set (symptoms, signs and tests as well as DS models).

RESULTS

In hierarchical summary receiver operating characteristic (HSROC) analysis, the area under curve (AUC) values for i) symptoms ii) signs and tests iii) DS were as follows: i) AUC=0.608 [95% confidence interval (CI)=0.550-0.666]; ii) AUC=0.621 (95% CI=0.570-0.672) and iii) AUC=0.877 (95% CI=0.835-0.919). The differences between these AUC values (roccomp analysis) are as follows: between i) and ii) p=0.715; between i) and iii) p<0.0001; between ii) and iii) p<0.0001.

CONCLUSION

The present study is the first to provide evidence that the DS could be used in diagnosis of NOD. The major advantage of our DS is that this model does not need radiology or endoscopy to reach high diagnostic accuracy.

Functional Dyspepsia: Diagnostic and Therapeutic Approaches

Functional dyspepsia is a common functional gastrointestinal (GI) disorder of gastroduodenal origin, diagnosed clinically in the presence of prototypical symptoms of epigastric pain and meal-related symptoms, and without structural explanation. The most recent diagnostic criteria provide for two functional dyspepsia subtypes, epigastric pain syndrome (EPS) and post-prandial distress syndrome (PDS) based on the predominant symptom pattern. The evaluation of dyspepsia should keep laboratory, imaging, and invasive testing to a minimum, as extensive or repetitive investigations are of rather low diagnostic yield in the absence of localizing symptoms or alarm features. Factors with etiopathologic relationships to functional dyspepsia include micro-inflammation, GI infections, abnormalities of gastroduodenal motility, visceral hypersensitivity, disturbances along the brain-gut axis, and psychological factors; all of these causative mechanisms have potential to partially explain symptoms in some functional dyspepsia patients, thus providing a rationale for the efficacy of a diversity of therapeutic approaches to functional dyspepsia. Management of dyspepsia symptoms relies upon both pharmacologic treatments and non-pharmacologic approaches, including psychological and complementary interventions. The evidence in support of established functional dyspepsia therapies is reviewed, and forms the basis for an effective functional dyspepsia treatment strategy emphasizing the patient's current symptom severity, pattern, and impact on the function and quality of life of the individual.

Secretin effects on gastric functions, hormones and symptoms in functional dyspepsia and health: randomized crossover trial

Abnormal gastric accommodation (GA) and gastric emptying contribute to pathophysiology in functional dyspepsia (FD). Secretin is a key regulator of GA in animal studies. Our aim was to study the effects of secretin on gastric motility, satiation, postprandial symptoms, and key hormones. We performed two double-blind, randomized, saline-controlled crossover trials in 10 healthy volunteers and 10 patients with FD by Rome IV criteria. We used measured GA (by validated SPECT method) after a ¹¹¹In radiolabeled Ensure 300-mL meal and quantified gastric emptying for 30 min by scintigraphy. Satiation was measured by volume to fullness (VTF) and maximum tolerated volume (MTV) on an Ensure nutrient drink test and postprandial symptoms 30 min post-MTV. Fasting and postprandial GLP-1, GIP, and HPP were measured. The ages and sex distribution of healthy controls and patients with FD were similar. Compared with placebo, secretin delayed gastric emptying at 30 min in both health [-11% (-16, -4), P = 0.004]; and FD [-8% (-9, 0), P = 0.03]. Satiation (VTF and MTV), GA, and plasma levels of GLP-1, GIP, and HPP did not differ between treatment arms in health or FD. On ANCOVA analysis (adjusting for age and sex), secretin did not consistently increase postprandial symptoms in health or FD. Secretin delayed gastric emptying in both health and FD without significantly altering GA, VTF, or MTV or selected hormones. Thus, secretin receptor activation may provide a novel therapeutic mechanism for patients with FD and rapid gastric emptying.NEW & NOTEWORTHY The naturally occurring hormone secretin retards gastric emptying of solids without deleteriously affecting gastric accommodation, satiation, other upper gastrointestinal hormones, or postprandial symptoms. Given these findings, a subset of patients with rapid gastric emptying (e.g., the estimated 20% of patients with functional dyspepsia) could be candidates for treatments that stimulate a secretin receptor such as sacubitril, which inhibits neprilysin, an enzyme that degrades secretin.

Review article: treatment options for functional dyspepsia

BACKGROUND

Functional dyspepsia, consisting of epigastric pain syndrome and postprandial distress syndrome, is a prevalent functional gastrointestinal disorder. To date, only limited treatment options are available and conflicting results in terms of efficacy have been reported. Consequently, nonpharmacological treatment options are increasingly being explored for functional dyspepsia.

AIM

To provide an overview of current pharmacological and nonpharmacological treatment options for functional dyspepsia.

METHODS

A literature search was conducted on Pubmed and other sources to identify relevant studies.

RESULTS

Acid suppressive therapy reduced symptoms in 30%-70% of the patients, with higher benefit in epigastric pain syndrome and superior effectiveness for proton pump inhibitors compared to H₂ -antagonists. Prokinetic agents, primarily used to treat postprandial distress syndrome, showed variable efficiency: 59%-81% responder rate for dopamine receptor antagonists, 32%-91% for serotonin-4-receptor agonists and 31%-80% for muscarinic receptor antagonists. H Pylori eradication, recommended in infected patients, was effective in 24%-82%. Refractory symptoms are addressed with neuromodulators. However, their efficacy in functional dyspepsia remains incompletely elucidated, available data showing symptom reduction in 27%-71% of the patients. Regarding herbal agents, peppermint oil reduced symptoms in 66%-91%, rikkunshito in 29%-34% and iberogast in 20%-95%. Lastly, acupuncture, cognitive behavioural therapy and hypnotherapy may help to provide symptom control, but research on their efficacy remains sparse.

CONCLUSIONS

None of the available therapies is effective in the majority of patients without being associated with major side effects. Developing new treatment options is challenging due to the heterogeneity of functional dyspepsia, the lack of readily identified target mechanisms and the poor association between pathophysiological disturbances and symptoms.

The Unfulfilled Promise of Prokinetics for Functional Dyspepsia/Postprandial Distress Syndrome

Functional dyspepsia (FD) is subdivided into epigastric pain syndrome and postprandial distress syndrome according to the Rome IV consensus. Based on the assumption that disordered gastric motility is a key pathophysiologic factor in postprandial distress syndrome, prokinetic agents are often proposed as the treatment of choice for this subgroup. Although a meta-analysis suggests that prokinetic agents may be efficacious and safe in FD, there is a lack of widely available agents of proven efficacy. This review analyzes some of the difficulties and challenges in establishing therapeutic efficacy of prokinetic drugs in FD.

Development of a real-time patient-reported outcome measure for symptom assessment in patients with functional dyspepsia using the experience sampling method

BACKGROUND

Patient-reported outcome measures (PROMs) are used to assess symptoms in patients with functional dyspepsia (FD). Current end-of-day questionnaires have several limitations including sensitivity to recall and ecological bias. The experience sampling method (ESM) is characterized by random and repeated assessments across momentary states in daily life and therefore less sensitive to these limitations. This study describes the development of a novel PROM based on ESM technology.

METHODS

An initial draft of the PROM was developed based on literature. Focus group interviews with FD patients according to Rome IV criteria, and an expert meeting with international opinion leaders in the field of functional gastrointestinal disorders were conducted in order to select items for the PROM. Cognitive interviews were performed to evaluate patients' understanding of the selected items and to create the definitive PROM.

KEY RESULTS

A systematic literature search revealed 59 items across four domains (ie, physical status; mood and psychological factors; context and environment; and nutrition, medication, and substance use). After patient focus group interviews and an international expert meeting, the number of items was reduced to 33. Cognitive interviews resulted in some minor linguistic changes in order to improve patients' understanding.

CONCLUSIONS AND INFERENCES

A novel digital ESM-based PROM for real-time symptom assessment in patients with functional dyspepsia was developed. This novel PROM has the potential to identify individual symptom patterns and specific triggers for dyspeptic symptoms, and optimize treatment strategies.

Gastroduodenal motility disorders

PURPOSE OF REVIEW

This review summarizes recent progress in the epidemiology, pathophysiology and treatment of gastroduodenal motility disorders with an emphasis on functional dyspepsia and gastroparesis.

RECENT FINDINGS

Pathophysiological research has focused on the association of delayed emptying and impaired accommodation with symptom pattern. Studies also confirmed the presence of altered mucosal integrity and low-grade immune activation in the duodenum in functional dyspepsia, while changes in numbers of interstitial cells of Cajal and myenteric neurons were confirmed in gastroparesis. Treatment advances in gastroparesis include new prokinetics such as the ghrelin receptor agonist relamorelin and the antiemetic agent aprepitant. The efficacy and use of neuromodulators were reviewed and new management guidelines for functional dyspepsia were published.

SUMMARY

Pathophysiological research has focused on cellular changes in gastroparesis and gastroduodenal motility disorders. New treatments include relamorelin and aprepitant for gastroparesis.

New developments in the treatment of gastroparesis and functional dyspepsia

Functional dyspepsia (FD) and gastroparesis are frequent causes of upper gastrointestinal symptoms such as postprandial fullness, early satiation, epigastric pain or burning, upper abdominal bloating, bothersome belching, nausea and vomiting. The underlying pathophysiological mechanisms are heterogeneous and involved mechanisms such as abnormal gastric motility (accommodation, emptying), visceral hypersensitivity, low grade mucosal inflammation and cellular changes in enteric nerves, muscle or interstitial cells of Cajal. Patient-reported outcomes for evaluating treatment efficacy in these conditions were recently developed and validated. Prokinetic agents, which enhance gastric motility, are used for treating both gastroparesis and FD. In FD, besides acid suppressive therapy and Helicobacter pylori eradication, neuromodulators and drugs that enhance gastric accommodation can be applied. In gastroparesis, anti-emetics may also provide symptom relief. Novel approaches under evaluation in these conditions are the fundus relaxing agents acotiamide and buspirone and the antidepressant mirtazapine in FD. For gastroparesis, recently studied agents include the prokinetic ghrelin agonist relamorelin, the prokinetic serotonergic agents velusetrag and prucalopride, the anti-emetic aprepitant and per-endoscopic pyloric myotomy procedures.

Systematic review: Disease-specific instruments to assess gastrointestinal symptoms in functional dyspepsia

BACKGROUND

Functional dyspepsia (FD) is a common functional gastrointestinal disorder with incompletely understood pathophysiology and heterogeneous symptom presentation. Assessment of treatment efficacy in FD is a methodological challenge as response to treatment must be assessed primarily by measuring subjective symptoms. Therefore, the use of patient-reported outcome measures (PROMs) is recommended by regulatory authorities to assess gastrointestinal symptoms in clinical trials for FD. In the last decades, a multitude of outcome measures has been developed. However, currently no PROM has been approved by the regulatory authorities, and no consensus has been reached with regard to the most relevant outcome measure in FD.

PURPOSE

This systematic review discusses the available disease-specific outcome measures for assessment of FD symptoms with psychometric validation properties, strengths, and limitations. Moreover, recommendations for use of current available outcome measures are provided, and potential areas of future research are discussed.