Recommendations for pharmacological clinical trials in children with irritable bowel syndrome: the Rome foundation pediatric subcommittee on clinical trials

Irritable bowel syndrome in children: the placebo response rate and influencing factors a meta-analysis

BACKGROUND

Irritable bowel syndrome is common in children and exhibits a high placebo response. This study was to explore the placebo response rate and its influencing factors in children with irritable bowel syndrome.

METHODS

A systematic search was performed on Pubmed, Embase, MEDLINE, Cochrane Library, CNKI, Wanfang, and CBM from database inception to March 2022. Randomized controlled trials of irritable bowel syndrome in children were included in the study. The primary outcome was the placebo response rate of improvement.

RESULTS

Thirteen studies were included, with 445 patients in the placebo group. The rate of improvement and abdominal pain disappearance were 28.2% (95% CI, 16.6-39.9%) and 5% (95% CI, 0-18.4%). The placebo response based on the abdominal pain score was 0.675 (95% CI, 0.203-1.147). The mode of administration (P < 0.01), dosing schedule (P < 0.01), and clinical outcome assessor (P = 0.04) have a significant impact on the magnitude of placebo effect.

CONCLUSIONS

The placebo response rate for pediatric irritable bowel syndrome was 28.2%. In clinical trials, reducing dosing frequency, selecting appropriate dosage forms, and using patient-reported outcomes can help mitigate the placebo effect.

IMPACT

This is the first meta-analysis to assess the placebo response rates for improvement and disappearance in children with IBS. The finding suggested that the mode of administration, dosing schedule, and clinical outcome assessor could potentially influence the magnitude of the placebo effect in children with IBS. This study would provide a basis for estimating sample size in clinical trial design with a placebo control.

First study to assess the reliability of commonly used pain scales in children with disorders of gut-brain interaction

BACKGROUND

There are no validated measures to assess chronic abdominal pain (AP) in clinical trials of children with disorders of gut-brain interaction (DGBIs). Currently used AP measures are extrapolated from studies on adults or children with acute AP. The primary aim of the study was to assess the commonly used pain scales in children with DGBIs. The secondary aim of the study was to compare specific pain measures with the overall subjective assessment of AP well-being in children.

METHODS

A sub-study from multicenter crossover randomized controlled trial (RCT) was conducted. Children with AP-DGBIs completed daily diaries for 7 weeks. It included three widely used AP scales: the numeric rating scale (NRS), the visual analog scale (VAS), the Faces Pain Scale Revised (FPS-R), and a global improvement question. Strength of correlations among scales and questions was assessed with the Pearson correlation coefficient (r).

KEY RESULTS

Thirty subjects completed the study. Children completed 4975 of 5880 (84.6%) pain and global responses. The VAS and NRS had strongest correlation among them, r = 0.893 (p < 0.001). The FPS-R also demonstrated strong correlations with the VAS r = 0.773 (p < 0.001), NRS = 0.783 (p < 0.001). The three scales exhibited weaker but significant correlations with the global question. Strong correlations were consistent when stratified by age groups.

CONCLUSION

This is the first study to assess the most used AP scales in children with DGBIs. It supports the Rome IV recommendations on using the VAS and NRS scales. It also suggests that FPS-R, that was not part of Rome IV, can also be used in RCTs. Congruent with the biopsychosocial model, there was a weaker correlation between AP measures and the global question. This suggests that the global question measures more domains than AP alone and that it should also be incorporated in DGBIs RCTs in children.

Home-based guided hypnotherapy for children with functional abdominal pain and irritable bowel syndrome in primary care: study protocol for a randomised controlled trial

INTRODUCTION

Children often present to primary care with functional abdominal pain (FAP) or irritable bowel syndrome (IBS), and around half still have abdominal complaints 1 year later. Hypnotherapy is an evidence-based treatment that is used in specialist care, but it lacks evidence in primary care. This study will investigate the (cost) effectiveness of home-based guided hypnotherapy for children with FAP or IBS in primary care.

METHODS AND ANALYSIS

We report the design of a pragmatic randomised controlled trial among children aged 7-17 years, diagnosed with FAP or IBS by their general practitioner (GP), with assessments over 12 months. The control group will receive care as usual (CAU) by their GP (eg, communication, education and reassurance), while the intervention group will receive CAU plus 3 months of home-based guided hypnotherapy via a website. The primary outcome will be the proportion of children with adequate relief from abdominal pain/discomfort at 12 months, analysed on an intention-to-treat basis. Secondary outcomes will include the adequacy of pain relief at 3 and 6 months, pain/discomfort severity, pain frequency and intensity, daily functioning and impact on function, anxiety and depression, pain beliefs, sleep disturbances, school absence, somatisation, and healthcare use and costs. We must include 200 children to determine a 20% difference in those with adequate relief (55% control vs 75% intervention).

ETHICS AND DISSEMINATION

The Medical Ethics Review Committee of the University Medical Center Groningen, the Netherlands, approved this study (METc2020/237). The results will be disseminated to patients, GPs and other stakeholders via email, a dedicated website, peer-reviewed publications and presentations at national and international conferences. We plan to collaborate with the Dutch Society of GPs to implement the results in clinical practice.

TRIAL REGISTRATION NUMBER

NCT05636358.

Efficacy and Safety of the Adjuvant Use of Probiotic Bacillus clausii Strains in Pediatric Irritable Bowel Syndrome: A Randomized, Double-Blind, Placebo-Controlled Study

OBJECTIVES

Current irritable bowel syndrome (IBS) treatments have limited efficacy and probiotics like Bacillus clausii (B. clausii) were found to be effective in the management of several gastrointestinal disorders. This phase III trial assessed the efficacy and safety of adding B. clausii (four strains: O/C, N/R, SIN, T), versus placebo, to conventional treatment of pediatric IBS in Mexico.

METHODS

Patients aged 6-17 years 11 months with IBS (Rome IV) for at least 2 months were randomized to receive either B. clausii (oral suspension, total dose 4 billion spores/day) or placebo once daily for 8 weeks. All patients also received conventional treatment. The primary endpoint was the difference in the proportion of patients with clinical improvements at Week 8 (Global Assessment Questions [GAQ]). Secondary endpoints included responders by Subject's Global Assessment of Relief for Children with IBS (SGARC); number/consistency of stools; abdominal distention/bloating; abdominal pain/intensity; and IBS behavior.

RESULTS

73.6% (95% confidence interval [CI] 67.3-80.0; B. clausii n = 129) and 78.5% (95% CI 72.5-84.4; placebo n = 130) of patients had symptom improvement (p = 0.8182). For Week 8 SGARC, 19.2% (B. clausii) and 20.9% (placebo) reported complete symptom relief. Stool evaluations, bloating, abdominal pain/intensity, and IBS behavior were similar between groups. Both treatments were well tolerated.

CONCLUSION

No significant differences in efficacy between B. clausii and placebo were demonstrated in addition to conventional treatment. The sample size calculation was based on an expected placebo/conventional treatment response of 30-40%. However, the actual treatment response observed was 80% and, thus, a study with larger population would be warranted. In addition, this study was conducted during the COVID-19 pandemic, when such controlled social conditions may have resulted in better diet, greater family stability, less psychological stress, and lower risk of infections exacerbating IBS, thereby improving symptoms in both groups.

EUDRACT NUMBER

2018-004519-31.

FODMAP dietary restrictions in the management of children with functional abdominal pain disorders: A systematic review

BACKGROUND

Evidence for the management of pediatric functional abdominal pain disorders (FAPD) is lacking. The aim of this systematic review was to update evidence on the efficacy and safety of implementing low fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAPs) dietary restrictions for the management of children with FAPD.

METHODS

The Cochrane Library, EMBASE, and MEDLINE databases were searched up to October 2021 for randomized controlled trials (RCTs) that compared the use of a low-FODMAP diet with any comparator in children aged 3-18 years with FAPD. The primary outcome was abdominal pain intensity.

KEY RESULTS

Five RCTs assessing the effects of a low-FODMAP diet were included. An effect of a low-FODMAP diet on abdominal pain intensity was only found in two trials. In one trial, there was a decrease in abdominal pain intensity on a 0-10 point Visual Analogue Scale (VAS) between low-FODMAP and gastrointestinal protective diet groups after 2 months (mean difference, MD 1.77, 95% confidence interval, CI, 1.23 to 2.31, n = 60). In another trial, there was a difference in abdominal pain intensity during the 3-day intervention between the low-FODMAP and typical Singaporean diet groups (MD -1.36 cm, 95% CI -2.38 to -0.34, n = 10) measured using a 0-10 cm VAS.

CONCLUSIONS & INTERFERENCES

There is insufficient evidence for or against the efficacy and safety of using a low-FODMAP diet for the management of children with FAPD.

Long-Term Follow-up of Individual Therapist Delivered and Standardized Hypnotherapy Recordings in Pediatric Irritable Bowel Syndrome or Functional Abdominal Pain

OBJECTIVES

We previously showed that standardized home-based gut-directed hypnosis exercises with compact disc (CD) is non-inferior to individual hypnotherapy (iHT) by a therapist in the treatment of children with irritable bowel syndrome (IBS) and functional abdominal pain (syndrome) (FAP(S)). Aim of this follow-up study was to investigate the long-term effects of standardized-hypnosis-recordings at home in comparison to iHT.

METHODS

All participants from our previous randomized controlled trial were invited to complete: 1) an online standardized abdominal pain dairy, on which pain frequency and intensity were scored, and 2) an online questionnaire including adequate relief (AR), anxiety/depression scores, somatization, quality of life (QOL), pain beliefs, school and/or work absenteeism and health care utilization.

RESULTS

227 out of 250 (91%) participants completed this study. After a median duration of 6 years follow-up (5.8-6.2), 80.0% in the CD group vs 86.6% in the iHT group reported AR of their abdominal complaints (P=.22). Compared to the 1-year follow-up, AR percentages were stable. Treatment success was seen in 67.6% in the CD group vs 71.3% in the iHT group (P=.66). Anxiety and depression scores, somatization, pain beliefs, health care utilization and school/work absenteeism also improved significantly in both study groups compared with baseline. No differences were found in QOL-scores.

CONCLUSIONS

Both home-based treatment with standardized-hypnosis-recordings and iHT given by a therapist show persisting positive results in more than 80% of children with IBS and FAP(S) after 6 years of follow-up. These results support the rationale for implementation of this easy-to-use, widely available and cost-effective home-treatment in daily practice.

Dietary interventions for functional abdominal pain disorders in children: a systematic review and meta-analysis

BACKGROUND

Functional abdominal pain disorders (FAPDs) are common among children and are associated with decreased quality of life and school attendance. Several dietary interventions have been suggested to improve symptoms of FAPDs. This systematic review assessed the efficacy and safety of dietary interventions for pediatric FAPDs.

DESIGN AND METHODS

Electronic databases were searched (inception-October 2021). Systematic reviews or RCTs were included if children (4-18 years) with FAPDs were treated with dietary interventions and compared to placebo, no diet or any other diet. Data extraction and assessment of quality of evidence based on GRADE system was independently performed by two review authors. Outcomes were treatment success, pain intensity and frequency, and withdrawal due to adverse events.

RESULTS

Twelve articles were included, representing data of 819 pediatric FAPD patients. Trials investigating fibers, FODMAP diet, fructans, fructose-restricted diet, prebiotic (inulin), serum-derived bovine immunoglobulin, and vitamin D supplementation were included. We found very low-certainty evidence that the use of fibers leads to higher treatment success (NNT = 5).

CONCLUSION

Based on current evidence, the use of fibers can be discussed in daily practice. High-quality intervention trials are highly needed to investigate if other dietary interventions are effective in the treatment of pediatric FAPD.

Clinical trials of probiotics in patients with IBS - some points to consider

Probiotic products in various formulations are widely used world-wide for a seemingly limitless range of indications--from health maintenance to the alleviation of common intestinal ailments and on to the prevention and treatment of a variety of gastrointestinal diseases and disorders. The profusion of probiotic preparations, together with a very different regulatory climate compared to that which surrounds drugs and devices, leaves the consumer and the health care professional alike bewildered. How can they tell which products truly are what they claim to be? Which probiotics should be chosen for a particular clinical situation? These questions are thrown into stark relief when one evaluates the literature on probiotics in irritable bowel syndrome. To provide some guidance the current probiotic landscape is reviewed and some achievable steps to help bring light to a murky environment are proposed. The goal is to promote verifiable quality control and generate actionable evidence from well-conducted clinical trials of probiotic products in irritable bowel syndrome.

Mediation of outcomes for cognitive behavioral therapy targeted to parents of children with Functional Abdominal Pain Disorders

OBJECTIVE

There is a large body of evidence for the efficacy of Cognitive Behavioral Therapy (CBT) in treating Functional Abdominal Pain Disorders (FAPD) in children. In most CBT interventions for FAPD, parents participate together with their children. However, only one study to date has examined targeting parents alone for treatment. The aim of the current study was to examine mediators of a parent-only CBT treatment incorporating social learning (SLCBT) for FAPD in children.

METHODS

We examined mediators of child outcomes in an existing randomized controlled trial (n = 316) of parent-only social learning CBT compared to an education condition. Hypothesized mediators (parental protectiveness, perceived threat of pain, catastrophizing) were assessed at 3 months post-treatment, and outcomes (parent ratings of disability, quality of life, school absences, and health care visits) were assessed at 6 months post-treatment. Mediation analyses were performed using Hayes' PROCESS macro.

RESULTS

Pain catastrophizing significantly mediated treatment effects for all outcomes (B ranged from -1.65 to 2.22). Reduction in pain threat was a significant mediator for all outcomes (B ranged from -1.84 to 3.13) except school absences and health care visits. Decrease in parental protectiveness mediated effects on disability and missed school (B ranged from -1.47 to 1.34). Mediation effects did not differ by in-person or remote delivery of SLCBT.

CONCLUSION

Changes in maladaptive parental thoughts and behaviors following parent-only SLCBT intervention appeared to mediate the effects of the intervention. Parental catastrophizing appears to be a particularly important target given that decreases in that variable mediated all outcomes.

Dance and yoga reduced functional abdominal pain in young girls: A randomized controlled trial

BACKGROUND

Functional abdominal pain disorders (FAPDs) affect children, especially girls, all over the world. The evidence for existing treatments is mixed, and effective accessible treatments are needed. Dance, a rhythmic cardio-respiratory activity, combined with yoga, which enhances relaxation and focus, may provide physiological and psychological benefits that could help to ease pain.

OBJECTIVES

The aim of this study was to evaluate the effect of a dance and yoga intervention on maximum abdominal pain in 9- to 13-year- old girls with FAPDs.

METHODS

This study was a prospective randomized controlled trial with 121 participants recruited from outpatient clinics as well as the general public. The intervention group participated in dance and yoga twice weekly for 8 months; controls received standard care. Abdominal pain, as scored on the Faces Pain Scale-Revised, was recorded in a pain diary. A linear mixed model was used to estimate the outcomes and effect sizes.

RESULTS

Dance and yoga were superior to standard health care alone, with a medium to high between-group effect size and significantly greater pain reduction (b = -1.29, p = 0.002) at the end of the intervention.

CONCLUSIONS

An intervention using dance and yoga is likely a feasible and beneficial complementary treatment to standard health care for 9- to 13-year-old girls with FAPDs.

SIGNIFICANCE

FAPDs affect children, especially girls, all over the world. The negative consequences such as absence from school, high consumption of medical care and depression pose a considerable burden on children and their families and effective treatments are needed. This is the first study examining a combined dance/yoga intervention for young girls with FAPDs and the result showed a reduction of abdominal pain. These findings contribute with new evidence in the field of managing FAPDs in a vulnerable target group.

Pharmacologic Treatment in Functional Abdominal Pain Disorders in Children: A Systematic Review

CONTEXT

Functional abdominal pain disorders (FAPDs) are common in childhood, impacting quality of life and school attendance. There are several compounds available for the treatment of pediatric FAPDs, but their efficacy and safety are unclear because of a lack of head-to-head randomized controlled trials (RCTs).

OBJECTIVE

To systematically review the efficacy and safety of the pharmacologic treatments available for pediatric FAPDs.

DATA SOURCES

Electronic databases were searched from inception to February 2021.

STUDY SELECTION

RCTs or systematic reviews were included if the researchers investigated a study population of children (4-18 years) in whom FAPDs were treated with pharmacologic interventions and compared with placebo, no treatment, or any other agent.

DATA EXTRACTION

Two reviewers independently performed data extraction and assessed their quality. Any interresearcher disagreements in the assessments were resolved by a third investigator.

RESULTS

Seventeen articles representing 1197 children with an FAPD were included. Trials investigating antispasmodics, antidepressants, antibiotics, antihistaminic, antiemetic, histamine-2-receptor antagonist, 5-HT4-receptor agonist, melatonin, and buspirone were included. No studies were found on treatment with laxatives, antidiarrheals, analgesics, antimigraines, and serotonergics.

LIMITATIONS

The overall quality of evidence on the basis of the Grading of Recommendations, Assessment, Development and Evaluations system was very low to low.

CONCLUSIONS

On the basis of current evidence, it is not possible to recommend any specific pharmacologic agent for the treatment of pediatric FAPDs. However, agents such as antispasmodics or antidepressants can be discussed in daily practice because of their favorable treatment outcomes and the lack of important side effects. High-quality RCTs are necessary to provide adequate pharmacologic treatment. For future intervention trials, we recommend using homogenous outcome measures and instruments, a large sample size, and long-term follow-up.

A Low-FODMAP Diet in the Management of Children With Functional Abdominal Pain Disorders: A Protocol of a Systematic Review

The available interventions for the management of children with functional abdominal pain disorders (FAPD) are limited. A diet low in fermentable oligosaccharides, disaccharides monosaccharides, and polyols (FODMAPs) is widely used in adults and children with FAPD, despite limited available evidence. We aim to systematically review evidence on the efficacy and safety of using a low-FODMAP diet for the management of children with FAPD.

Methods

The Cochrane Library, EMBASE, and MEDLINE databases will be searched for randomized controlled trials (RCTs) that compare the use a low-FODMAP diet (preferably a 3-step low-FODMAP diet but also only a strict low-FODMAP diet or restriction of individual FODMAPs) with any comparator (i.e., standardized [i.e., average national] or other diet or no intervention) in children with FAPD (regardless of the definition). Each FAPD and each low-FODMAP diet or individual FODMAP restriction will be assessed separately. The Cochrane Collaboration's tool for assessing the risk of bias will be used. The primary outcome will be the abdominal pain intensity. The secondary outcomes will be abdominal pain frequency, stool consistency, other gastrointestinal symptoms, school performance, and psychological functioning associated with FAPD, parent's work absenteeism associated with FAPD of a child, health-related quality of life, compliance, growth, and adverse events. The findings will be published in a peer-reviewed journal and submitted to relevant conferences.

Conclusion

This systematic review of rigorous methodological design will update current evidence on the efficacy and safety of using a low-FODMAP diet. However, it may be limited by the quality of the included studies.

Antidepressants for functional abdominal pain disorders in children and adolescents

BACKGROUND

Functional Abdominal Pain Disorders (FAPDs) present a considerable burden to paediatric patients, impacting quality of life, school attendance and causing higher rates of anxiety and depression disorders. There are no international guidelines for the management of this condition. A previous Cochrane Review in 2011 found no evidence to support the use of antidepressants in this context.

OBJECTIVES

To evaluate the current evidence for the efficacy and safety of antidepressants for FAPDs in children and adolescents.

SEARCH METHODS

In this updated review, we searched the Cochrane Library, PubMed, MEDLINE, Embase, PsycINFO and two clinical trial registers from inception until 03 February 2020. We also updated our search of databases of ongoing research, reference lists and 'grey literature' from inception to 03 February 2020.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing antidepressants to placebo, to no treatment or to any other intervention, in children aged 4 to 18 years with a FAPD diagnosis as per the Rome or any other defined criteria (as defined by the authors). The primary outcomes of interest included treatment success (as defined by the authors), pain severity, pain frequency and withdrawal due to adverse events.

DATA COLLECTION AND ANALYSIS

Two review authors checked all citations independently, resolving disagreement with a third-party arbiter. We reviewed all potential studies in full text, and once again made independent decisions, with disagreements resolved by consensus. We conducted data extraction and 'Risk of bias' assessments independently, following Cochrane methods. Where homogeneous data were available, we performed meta-analysis using a random-effects model. We conducted GRADE analysis.

MAIN RESULTS

We found one new study in this updated search, making a total of three trials (223 participants) eligible for inclusion: two using amitriptyline (AMI) and one using citalopram. For the primary outcome of treatment success, two studies used reports of success on a symptom-based Likert scale, with either a two-point reduction or the two lowest levels defined as success. The third study defined success as a 15% improvement in quality of life (QOL) ratings scales. Therefore, meta-analysis did not include this final study due to the heterogeneity of the outcome measure. There is low-certainty evidence that there may be no difference when antidepressants are compared with placebo (risk ratio (RR) 1.17, 95% confidence interval (CI) 0.87 to 1.56; 2 studies, 205 participants; I2 = 0%). We downgraded the evidence for significant imprecision due to extremely sparse data (see Summary of findings table 1). The third study reported that participants receiving antidepressants were significantly more likely than those receiving placebo to experience at least a 15% improvement in overall QOL score at 10 and 13 weeks (P = 0.007 and P = 0.002, respectively (absolute figures were not given)). The analysis found no difference in withdrawals due to adverse events between antidepressants and placebo: RR 3.17 (95% CI 0.65 to 15.33), with very low certainty due to high risk of bias in studies and imprecision due to low event and participant numbers. Sensitivity analysis using a fixed-effect model and analysing just for AMI found no change in this result. Due to heterogeneous and limited reporting, no further meta-analysis was possible.

AUTHORS' CONCLUSIONS

There may be no difference between antidepressants and placebo for treatment success of FAPDs in childhood. There may be no difference in withdrawals due to adverse events, but this is also of low certainty. There is currently no evidence to support clinical decision making regarding the use of these medications. Further studies must consider sample size, homogenous and relevant outcome measures and longer follow up.

Effect of a low-FODMAP diet for the management of functional abdominal pain disorders in children: a study protocol for a randomized controlled trial

Background

Evidence from studies in adults documents that fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAPs) may be triggers of symptoms in individuals with functional abdominal pain disorders (FAPDs). However, in children, the evidence is very limited. We aim to assess the effects of a low-FODMAP diet compared with a regular diet for the management of children with FAPDs.

Methods

We will perform a randomized, quadruple-blinded, controlled trial. Seventy-four children aged 8 to 18 years with a FAPD (Irritable Bowel Syndrome or Functional Abdominal Pain-Not Otherwise Specified), diagnosed according to the Rome IV criteria, will be randomly allocated to receive either a low-FODMAP diet or a regular diet for 4 weeks. The primary outcome will be the percentage of the responders, defined as the participants who have at least 30% improvement in abdominal pain intensity on a Visual Analogue Scale (VAS) during the last week of the trial compared with baseline, that is at least equal to the Reliable Change Index (≥ 25 mm change on VAS). Other outcomes will include changes in stool consistency, abdominal pain frequency, total scores on the Gastrointestinal Symptom Rating Scale, KIDSCREEN-10 Index and World Health Organization Five Well-Being Index, child’s school attendance and parents’ work absenteeism, and BMI-for-age z-score. Compliance, tolerability of the low-FODMAP diet, and adverse events also will be evaluated. Each FAPD subtype will be assessed separately.

Discussion

There is a need for high-quality evidence regarding the dietary management of children with FAPDs. This randomized controlled trial (RCT) of rigorous methodological design will help to establish the effectiveness, if any, of a low-FODMAP diet for the management of FAPDs in the pediatric population. The findings of this RCT will assist with the development of guidelines and influence the direction of further research.

Trial registration

NCT04528914

Data and protocol version identifier: 24/08/2020

Supplementary Information

The online version contains supplementary material available at 10.1186/s12937-020-00656-3.

Paediatric functional abdominal pain disorders

Paediatric functional abdominal pain disorders, currently referred to as disorders of gut-brain interaction, comprise irritable bowel syndrome, functional dyspepsia, abdominal migraine and functional abdominal pain not otherwise specified, as defined by the Rome IV diagnostic criteria. Functional abdominal pain disorders are common disorders with a prevalence of 3-16% depending on country, age and sex. A greater understanding of aetiopathogenesis and pathophysiology is emerging and includes intestinal components (inflammation, motility and the microbiota), central factors (psychological aspects, sensitization and/or differences in connectivity or activity of certain brain regions) as well as extrinsic factors (infections). In particular, the timing of disruption of the microbiota-gut-brain axis seems to be important. Diagnosis is challenging but is primarily based on clinical symptoms and exclusion of other organic causes, with an emphasis on avoiding unnecessary invasive diagnostic procedures. The available pharmacological interventions are limited in children and, therefore, management has focused on combined approaches, including mind-targeted interventions (hypnotherapy and cognitive behavioural therapy), diet (probiotics) and percutaneous electrical nerve field stimulation. The evidence for their clinical efficacy, although limited, is favourable, with positive impacts on symptoms and overall quality of life. The coming decades hold promise for improved understanding and management of these enigmatic disorders.

Efficacy of Auricular Neurostimulation in Adolescents With Irritable Bowel Syndrome in a Randomized, Double-Blind Trial

BACKGROUND & AIMS

Auricular neurostimulation therapy, in which a noninvasive device delivers percutaneous electrical nerve field stimulation (PENFS) to the external ear, is effective in pediatric patients with functional abdominal pain disorders. Preclinical studies showed that PENFS modulates central pain pathways and attenuates visceral hyperalgesia. We evaluated the efficacy of PENFS in adolescents with irritable bowel syndrome (IBS).

METHODS

We analyzed data from pediatric patients with IBS who participated in a double-blind trial at a tertiary care gastroenterology clinic from June 2015 through November 2016. Patients were randomly assigned to groups that received PENFS (n = 27; median age, 15.3 y; 24 female) or a sham stimulation (n = 23; median age, 15.6 y; 21 female), 5 days/week for 4 weeks. The primary endpoint was number of patients with a reduction of 30% or more in worst abdominal pain severity after 3 weeks. Secondary endpoints were reduction in composite abdominal pain severity score, reduction in usual abdominal pain severity, and improvement in global symptom based on a symptom response scale (-7 to +7; 0 = no change) after 3 weeks.

RESULTS

Reductions of 30% or more in worst abdominal pain were observed in 59% of patients who received PENFS vs 26% of patients who received the sham stimulation (P = .024). The patients who received PENFS had a composite pain median score of 7.5 (interquartile range [IQR], 3.6-14.4) vs 14.4 for the sham group (IQR, 4.5-39.2) (P = .026) and a usual pain median score of 3.0 (IQR, 3.0-5.0) vs 5.0 in the sham group (IQR, 3.0-7.0) (P = .029). A symptom response scale score of 2 or more was observed in 82% of patients who received PENFS vs 26% of patients in the sham group (P ≤ .001). No significant side effects were reported.

CONCLUSIONS

Auricular neurostimulation reduces abdominal pain scores and improves overall wellbeing in adolescents with IBS. PENFS is a noninvasive treatment option for pediatric patients with functional bowel disorders. ClinicalTrials.gov no: NCT02367729.

A Core Outcome Set for Clinical Trials in Pediatric Functional Abdominal Pain Disorders

OBJECTIVE

To ensure consistency and reduce outcome measure reporting heterogeneity in clinical trials on pediatric functional abdominal pain disorders (FAPDs), a core outcome set (COS) was developed for pediatric FAPD trials.

STUDY DESIGN

A mixed-method 2-round Delphi technique was used and key stakeholders, including healthcare professionals (HCPs), patients with FAPD, and their parents were invited to participate. In the first round, key stakeholders identified outcomes of importance through an open-ended questionnaire. Outcomes mentioned by ≥10% of the participants were included in a shortlist. In the second round, this shortlist was rated and prioritized. During a consensus meeting with an expert panel, the final COS was defined.

RESULTS

The first round was completed by 152 of 210 (72%) HCPs, 103 (100%) parents, and 50 of 54 (93%) patients. A total of 104 from 167 (62%) HCPs, 102 (100%) parents, and 53 (100%) patients completed round 2. Pain intensity, pain frequency, quality of life, school attendance, anxiety/depression, adequate relief, defecation pattern (disease specific, irritable bowel syndrome), and adverse events were included in the final COS for FAPDs.

CONCLUSION

A set of 8 core outcomes has been identified that should minimally be measured in pediatric FAPD trials. Implementation of the use of this COS will increase comparison between studies and, therefore, improve management of children with FAPDs.

New advances in the treatment of paediatric functional abdominal pain disorders

This Review summarises recent pharmacological and upcoming alternative interventions for children with functional abdominal pain disorders (FAPDs). Pharmacological targets include prokinetics and drugs affecting gastric accommodation to treat postprandial distress and nausea. Similarly, anti-inflammatory agents, junctional protein regulators, analgesics, secretagogues, and serotonin antagonists have a therapeutic role for irritable bowel syndrome. Non-pharmacological treatments include peripheral electrical nerve field stimulation to the external ear, gastric electrical stimulation, dietary interventions such as low fructose and fibre based diets, and nutraceuticals, which include probiotics, prebiotics, and synbiotics. Newer psychological advances such as exposure-based cognitive behavioural therapy, acceptance and commitment therapy, and mindfulness meditation are being investigated for paediatric functional pain. Lastly, alternative therapies such as acupuncture, moxibustion, yoga, and spinal manipulation are also gaining popularity in the treatment of FAPDs.

Definitions of Pediatric Functional Abdominal Pain Disorders and Outcome Measures: A Systematic Review

OBJECTIVE

To systematically review definitions of functional abdominal pain orders (FAPDs) and outcome measures used in therapeutic randomized controlled trials in pediatric FAPDs adhering to the Outcome Measures in Rheumatology recommendations.

STUDY DESIGN

Cochrane, MEDLINE, Embase, and Cinahl databases were systematically searched from inception to April 2018. English-written therapeutic randomized controlled trials concerning FAPDs in children aged 4-18 years were included. Definitions of FAPDs, interventions, outcome measures, measurement instruments, and outcome assessors of each study were tabulated descriptively. Quality was assessed using the Delphi List.

RESULTS

A total of 4771 articles were found, of which 64 articles were included (n = 25, 39% of high methodologic quality). The Rome III (50%), Rome II (17%), Apley (16%), and author-defined (17%) criteria were used to define FAPDs. Fourteen studies (22%) assessed a pharmacologic, 25 (39%) a dietary, and 25 (39%) a psychosocial intervention. Forty-four studies (69%) predefined their primary outcomes. In total, 211 reported predefined outcome measures were grouped into 23 different outcome domains; the majority being patient-reported (n = 27, 61%). Of the 14 studies that evaluated a pharmacologic intervention, 12 (86%) reported on adverse events.

CONCLUSIONS

Studies on pediatric FAPDs are of limited methodologic quality and show large heterogeneity and inconsistency in defining FAPDs and outcome measures used. Development of a core outcome set is needed to make comparison between intervention studies possible.

Multidisciplinary Treatment Reduces Pain and Increases Function in Children With Functional Gastrointestinal Disorders

Functional gastrointestinal disorders (FGIDs) are common in children and adolescents, frequently resulting in extensive testing, school absenteeism, disability, and poor quality of life.^1-3 FGIDs result from a complex interplay between genetic predisposition, biological triggers, and psychosocial triggers, and are best explained by the biopsychosocial model.¹ Although this implies the necessity of multidisciplinary treatment, studies showing the efficacy of such an intervention are lacking. We describe the outcome of children with severe FGIDs treated in a multidisciplinary program.

The Brussels Infant and Toddler Stool Scale: A Study on Interobserver Reliability

OBJECTIVES

The Bristol Stool Form Scale (BSFS) is inadequate for non-toilet trained children. The Brussels Infant and Toddler Stool Scale (BITSS) was developed, consisting of 7 photographs of diapers containing stools of infants and toddlers. We aimed to evaluate interobserver reliability of stool consistency assessment among parents, nurses, and medical doctors (MDs) using the BITSS.

METHODS

In this multicenter cross-sectional study (2016-2017), BITSS photographs were rated according to the BSFS. The reliability of the BITSS was evaluated using the overall proportion of perfect agreement and the linearly weighted κ statistic.

RESULTS

A total of 2462 observers participated: 1181 parents (48.0%), 624 nurses (25.3%), and 657 MDs (26.7%). The best-performing BITSS photographs corresponded with BSFS type 7 (87.5%) and type 4 (87.6%), followed by the BITSS photographs representing BSFS type 6 (75.0%), BSFS type 5 (68.0%), BSFS type 1 (64.8%), and BSFS type 3 (64.6%). The weakest performing BITSS photograph corresponded with BSFS type 2 (49.7%). The overall weighted κ-value was 0.72 (95% CI 0.59-0.85; good agreement). Based on these results, photographs were categorized per stool group as hard (BSFS type 1-3), formed (BSFS type 4), loose (BSFS types 5 and 6), or watery (BSFS type 7) stools. According to this new categorization system, correct allocation for each photograph ranged from 83 to 96% (average: 90%). The overall proportion of correct allocations was 72.8%.

CONCLUSIONS

BITSS showed good agreement with BSFS. Using the newly categorized BITSS photographs, the BITSS is reliable for the assessment of stools of non-toilet trained children in clinical practice and research. A multilanguage translated version of the BITSS can be downloaded at https://bitss-stoolscale.com/.

Multiple psychological factors predict abdominal pain severity in children with irritable bowel syndrome

BACKGROUND

Anxiety and depression are implicated as contributors to abdominal pain in pediatric irritable bowel syndrome (IBS) but is unclear if this pain is associated with other psychological factors. The study objective was to test if the impact of anxiety or depression on IBS symptom severity is mediated by somatization and/or pain catastrophizing.

METHODS

We utilized baseline data from local pediatric IBS clinical studies. Through mediation analysis, we assessed whether somatization or pain catastrophizing mediated (either independently or combined) the separate relationships of anxiety or depression with IBS abdominal pain severity.

KEY RESULTS

We analyzed 261 participants. All psychological factors were positively correlated with one another and IBS abdominal pain severity. The association of anxiety with IBS abdominal pain was mediated by both somatization and pain catastrophizing in individual analyses (each mediated standardized coefficient [β] 0.11, CI 0.05-0.18) and in multiple analysis (mediated standardized β 0.18, CI 0.09-0.27). The association of depression with IBS abdominal pain was also mediated by somatization (mediated standardized β 0.08, CI0.02-0.14) and pain catastrophizing (mediated standardized β 0.06, CI 0.01-0.11) in individual analyses and in multiple analysis (mediated standardized β 0.19, CI 0.04-0.19).

CONCLUSIONS AND INFERENCES

Somatization and pain catastrophizing mediate the relationships between anxiety/depression and IBS abdominal pain severity. These findings suggest that somatization and pain catastrophizing may be better treatment targets than anxiety and depression. Clinicians should assess these psychological factors in pediatric IBS patients and refer for intervention to improve outcomes.

Side effects associated with pharmacotherapy for pediatric irritable bowel syndrome and functional abdominal pain - not otherwise specified: a systematic review

INTRODUCTION

To systematically review the literature regarding the side effects of pharmacotherapy in children with irritable bowel syndrome (IBS) and functional abdominal pain - not otherwise specified (FAP-NOS). Areas covered: Cochrane Library, PubMed, and Embase databases were searched from inception to May 2018. The following inclusion criteria were applied: (1) randomized controlled trials (RCTs), cohort studies or case-control studies; (2) in children aged 4-18 years or adult studies if children are reported separately; (3) reporting a diagnosis of IBS or FAP-NOS as defined by the authors; and (4) reporting the occurrence of side effects of pharmacotherapy. Quality assessment of included studies was conducted. Expert opinion: A total of 4619 articles were identified; 17 were included. In 10/17 (59%) studies, side effects of pharmacotherapy (antispasmodics, antidepressants, antihistaminic agents, serotonergic agents and antibiotics) occurred. The majority of side effects were: (1) limited to the gastrointestinal tract and central nervous system and, 2) mild and transient. No serious adverse events were reported. This systematic review shows that data on safety in children with functional abdominal pain disorders are scarce, and highlights the lack of high-quality research for potential side effects of pediatric IBS and FAP-NOS. Further research by means of large well-designed-follow-up studies is necessary.

Effectiveness of Probiotics in Children With Functional Abdominal Pain Disorders and Functional Constipation: A Systematic Review

OBJECTIVE

The objective of this study was to investigate the effect of probiotics on functional abdominal pain disorders (FAPD) and functional constipation (FC).

METHODS

A systematic review was conducted, searching PubMed and Cochrane databases from inception to January 2018 for randomized controlled trials (RCTs) investigating the efficacy of probiotics in children aged 4 to 18 years with FAPD or children aged 0 to 18 years with FC.

RESULTS

A total of 657 citations were identified. Finally, 11 RCTs for FAPD and 6 RCTs for FC were included. Some evidence exists for Lactobacillus rhamnosus GG (n=3) in reducing frequency and intensity of abdominal pain in children with irritable bowel syndrome. There is no evidence to recommend L. reuteri DSM 17938 (n=5), a mix of Bifidobacterium infantis, Bifidobacterium breve and Bifidobacterium longum (n=1), Bifidobacterium lactis (n=1) or VSL#3 (n=1) for children with FAPD. No evidence exists to support the use of Lactobacillus casei rhamnosus LCR35 (n=1), B. lactis DN173 010 (n=1), B. longum (n=1), L. reuteri DSM 17938 (n=1), a mix of B. infantis, B. breve and B. longum (n=1), or Protexin mix (n=1) for children with FC. In general, studies had an unclear or high risk of bias.

CONCLUSIONS

Insufficient evidence exists for the use of probiotics in FAPD and FC, only L. rhamnosus GG seems to reduce frequency and intensity of abdominal pain but only in children with irritable bowel syndrome. A better understanding of differences in gut microbiota in health and disease might lead to better probiotic strategies to treat disease.

Recommendations for pharmacological clinical trials in children with functional constipation: The Rome foundation pediatric subcommittee on clinical trials

BACKGROUND

Evidence for the efficacy of commonly used drugs in the treatment of childhood functional constipation (FC) is scarce, studies are often of low quality and study designs are heterogeneous. Thus, recommendations for the design of clinical trials in childhood FC are needed.

PURPOSE

Members of the Rome Foundation and a member of the Pediatric Committee of the European Medicines Agency formed a committee to create recommendations for the design of clinical trials in children with FC.

KEY RECOMMENDATIONS

This committee recommends conducting randomized, double-blind, placebo-controlled, parallel-group clinical trials to assess the efficacy of new drugs for the treatment of childhood FC. Pediatric study participants should be included based on fulfilling the Rome IV criteria for FC. A treatment free run-in period for baseline assessment is recommended. The trial duration should be at least 8 weeks. Treatment success is defined as no longer meeting the Rome IV criteria for FC. Stool consistency should be reported based on the Bristol Stool Scale. Endpoints of drug efficacy need to be tailored to the developmental age of the patient population.

Fructans Exacerbate Symptoms in a Subset of Children With Irritable Bowel Syndrome

BACKGROUND & AIMS

Dietary fructans exacerbate symptoms in some, but not all, adults with irritable bowel syndrome (IBS). We sought to determine whether fructans worsen symptoms in children with IBS and whether clinical and psychosocial factors, and/or gas production, can identify those who are fructan sensitive.

METHODS

We performed a double-blind placebo-controlled (maltodextrin) cross-over trial of 23 children with IBS, based on pediatric Rome III criteria, from September 2014 through December 2016. At baseline, participants completed 1-week pain and stool diaries and a 3-day food record and psychosocial factors (depression, anxiety, and somatization) were measured. Subjects were randomly assigned to groups that were provided meals for 72 hours containing either fructans or maltodextrin (0.5 g/kg; maximum, 19 g). Following a washout period of 10 days or more, the subjects received the meal they were not given during the first study period (crossed over). Gastrointestinal symptoms and breath hydrogen and methane production were captured during each meal period. Fructan sensitivity was defined as an increase of 30% or more in abdominal pain frequency following fructan ingestion.

RESULTS

Subjects had more mean episodes of abdominal pain/day during the fructan-containing diet (3.4 ± 2.6) vs the maltodextrin-containing diet (2.4 ± 1.7) (P < .01), along with more severe bloating (P < .05) and flatulence (P = .01). Hydrogen (but not methane) production was greater while subjects were on the fructan-containing diet (617 ± 305 ppm∗h) than the maltodextrin-containing diet (136 ± 78 ppm*h) (P < .001). Eighteen subjects (78.2%) had more frequent abdominal pain while on the fructan-containing diet and 12 (52.2%) qualified as fructan sensitive. We found no difference between fructan-sensitive and fructan-insensitive subjects in baseline abdominal pain or bowel movement characteristics, dietary intake, psychosocial parameters, IBS subtype, or gas production.

CONCLUSIONS

In a randomized controlled trial of children with IBS, we found fructans to exacerbate several symptoms. However, fructan sensitivity cannot be identified based on baseline gastrointestinal symptoms, dietary intake, psychosocial factors, or gas production. Clinicaltrials.gov no: NCT02842281.

Assessing Children's Report of Stool Consistency: Agreement Between the Pediatric Rome III Questionnaire and the Bristol Stool Scale

OBJECTIVES

To assess the agreement between the Questionnaire on Pediatric Gastrointestinal Symptoms-Rome III (QPGS-RIII) and the Bristol Stool Scale (BSS) in evaluating stool consistency and the diagnosis of functional constipation in children.

STUDY DESIGN

Children aged 8-18 years were asked to describe their stool consistency in the previous month according to the QPGS-RIII and the BSS. Stool consistency according to both instruments was categorized into 3 categories: "hard," "normal," and "liquid." The children's reported stool consistency using the QPGS-RIII and the BSS were compared, and the intrarater agreement between the 2 instruments was measured using the Cohen kappa coefficient (κ). The diagnosis of functional constipation was based on the Rome III criteria, incorporating the assessment of stool consistency according to the QPGS-RIII and the BSS.

RESULTS

A total of 1835 children were included. Only slight agreement existed between the QPGS-RIII and the BSS for assessing stool consistency (κ = .046; P = .022). Significantly more children reported hard stools on the BSS compared to the QPGS-RIII (18.0% vs 7.1%; P = .000). The prevalence of functional constipation was 8.6% using the QPGS-RIII and 9.3% using the BSS (P = .134).

CONCLUSIONS

Only slight agreement exists between the QPGS-RIII and the BSS in the evaluation of stool consistency in children. Better instruments are needed to assess the consistency of stools with a high degree of reliability, both in research and in the clinical setting.

Neurostimulation for abdominal pain-related functional gastrointestinal disorders in adolescents: a randomised, double-blind, sham-controlled trial

BACKGROUND

Development of safe and effective therapies for paediatric abdominal pain-related functional gastrointestinal disorders is needed. A non-invasive, US Food and Drug Administration-cleared device (Neuro-Stim, Innovative Health Solutions, IN, USA) delivers percutaneous electrical nerve field stimulation (PENFS) in the external ear to modulate central pain pathways. In this study, we evaluated the efficacy of PENFS in adolescents with abdominal pain-related functional gastrointestinal disorders.

METHODS

In this randomised, sham-controlled trial, we enrolled adolescents (aged 11-18 years) who met Rome III criteria for abdominal pain-related functional gastrointestinal disorders from a single US outpatient gastroenterology clinic. Patients were randomly assigned (1:1) with a computer-generated randomisation scheme to active treatment or sham (no electrical charge) for 4 weeks. Patients were stratified by sex and presence or absence of nausea. Allocation was concealed from participants, caregivers, and the research team. The primary efficacy endpoint was change in abdominal pain scores. We measured improvement in worst abdominal pain and composite pain score using the Pain Frequency-Severity-Duration (PFSD) scale. Participants with less than 1 week of data and those with organic disease identified after enrolment were excluded from the modified intention-to-treat population. This trial has been completed and is registered with ClinicalTrials.gov, number NCT02367729.

FINDINGS

Between June 18, 2015, and Nov 17, 2016, 115 children with abdominal pain-related functional gastrointestinal disorders were enrolled and assigned to either PENFS (n=60) with an active device or sham (n=55). After exclusion of patients who discontinued treatment (n=1 in the PENFS group; n=7 in the sham group) and those who were excluded after randomisation because they had organic disease (n=2 in the PENFS group; n=1 in the sham group), 57 patients in the PENFS group and 47 patients in the sham group were included in the primary analysis. Patients in the PENFS group had greater reduction in worst pain compared with sham after 3 weeks of treatment (PENFS: median score 5·0 [IQR 4·0-7·0]; sham: 7·0 [5·0-9·0]; least square means estimate of change in worse pain 2·15 [95% CI 1·37-2·93], p<0·0001). Effects were sustained for an extended period (median follow-up 9·2 weeks [IQR 6·4-13·4]) in the PENFS group: median 8·0 (IQR 7·0-9·0) at baseline to 6·0 (5·0-8·0) at follow-up versus sham: 7·5 (6·0-9·0) at baseline to 7·0 (5·0-8·0) at follow-up (p<0·0001). Median PFSD composite scores also decreased significantly in the PENFS group (from 24·5 [IQR 16·8-33.3] to 8·4 [3·2-16·2]) compared with sham (from 22·8 [IQR 8·4-38·2] to 15·2 [4·4-36·8]) with a mean decrease of 11·48 (95% CI 6·63-16·32; p<0·0001) after 3 weeks. These effects were sustained at extended follow-up in the PENFS group: median 24·5 (IQR 16·8-33·3) at baseline to 12 (3·6-22·5) at follow-up, compared with sham: 22·8 (8·4-38·2) at baseline to 16·8 (4·8-33·6) at follow-up (p=0·018). Ten patients reported side-effects (three of whom discontinued the study): ear discomfort (n=6; three in the PENFS group, three in the sham group), adhesive allergy (n=3; one in the PENFS group, two in the sham group), and syncope due to needle phobia (n=1; in the sham group). There were no serious adverse events.

INTERPRETATION

Our results show that PENFS with Neuro-Stim has sustained efficacy for abdominal pain-related functional gastrointestinal disorders in adolescents. This safe and effective approach expands treatment options and should be considered as a non-pharmacological alternative for these disorders.

FUNDING

American Neurogastroenterology and Motility Society.

Lactobacillus reuteri DSM 17938 in the Treatment of Functional Abdominal Pain in Children: RCT Study

OBJECTIVES

Beneficial therapeutic effect of probiotics has been reported in children with the irritable bowel syndrome (IBS) but not consistently in other functional abdominal pain-related disorders. The aim of the present study was to investigate the effect of Lactobacillus reuteri DSM 17938 in the treatment of functional abdominal pain (FAP) and IBS in children.

METHODS

Children (age 4-18 years) referred to pediatric gastroenterologist at Children's Hospital Zagreb from May 2012 to December 2014, diagnosed as FAP or IBS, were randomized to receive L reuteri DSM 17938 10⁸ CFU daily or placebo. The study was a prospective, randomized, double-blind, placebo-controlled parallel study. Symptoms were evaluated using Wong-Baker FACES pain rating scale for pain and Bristol scale for stool shape and consistence.

RESULTS

Data were analyzed for 55 children (26 in the intervention group and 29 in the placebo group). Children in the intervention group had significantly more days without pain (median 89.5 vs 51 days, P = 0.029). Abdominal pain was less severe in children taking probiotics during the second month (P < 0.05) and fourth month (P < 0.01). The 2 groups did not differ in the duration of abdominal pain, stool type, or absence from school. Both groups experienced significant reduction in the severity of abdominal pain from first to fourth month, with the reduction more prominent in the intervention group (P < 0.001 vs P = 0.004).

CONCLUSIONS

Administration of L reuteri DSM 17938 was associated with a possible reduction of the intensity of pain and significantly more days without pain in children with FAP and IBS.

Brief telephone-delivered cognitive behavioral therapy targeted to parents of children with functional abdominal pain: a randomized controlled trial

Pediatric functional abdominal pain disorders (FAPDs) are associated with increased health care utilization, school absences, and poor quality of life (QoL). Cost-effective and accessible interventions are needed. This multisite study tested the effects of a 3-session cognitive behavioral intervention delivered to parents, in-person or remotely, on the primary outcome of pain severity and secondary outcomes (process measures) of parental solicitousness, pain beliefs, catastrophizing, and child-reported coping. Additional outcomes hypothesized a priori and assessed included functional disability, QoL, pain behavior, school absences, health care utilization, and gastrointestinal symptoms. The study was prospective and longitudinal (baseline and 3 and 6 months' follow-up) with 3 randomized conditions: social learning and cognitive behavioral therapy in-person (SLCBT) or by phone (SLCBT-R) and education and support condition by phone (ES-R). Participants were children aged 7 to 12 years with FAPD and their parents (N = 316 dyads). Although no significant treatment effect for pain severity was found, the SLCBT groups showed significantly greater improvements compared with controls on process measures of parental solicitousness, pain beliefs, and catastrophizing, and additional outcomes of parent-reported functional disability, pain behaviors, child health care visits for abdominal pain, and (remote condition only) QoL and missed school days. No effects were found for parent and child-reported gastrointestinal symptoms, or child-reported QoL or coping. These findings suggest that for children with FAPD, a brief phone SLCBT for parents can be similarly effective as in-person SLCBT in changing parent responses and improving outcomes, if not reported pain and symptom report, compared with a control condition.

The Placebo Response in Pediatric Abdominal Pain-Related Functional Gastrointestinal Disorders: A Systematic Review and Meta-Analysis

OBJECTIVE

To investigate the magnitude and determinants of the placebo response in studies with pediatric abdominal pain-related functional gastrointestinal disorders.

STUDY DESIGN

The Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, and CINAHL were searched for systematic reviews and randomized placebo-controlled trials concerning children 4-18 years of age with an abdominal pain-related functional gastrointestinal disorder. The primary outcome was the pooled proportion of subjects assigned to placebo with improvement as defined by the authors. The effect of trial characteristics on the magnitude of the placebo response was investigated using univariate meta-regression analysis.

RESULTS

Twenty-one trials were identified. The pooled proportion of subjects with improvement was 41% (95% CI, 34%-49%; 17 studies) and with no pain was 17% (95% CI, 8%-32%; 7 studies). The pooled standardized mean difference on the Faces Pain Scales compared with baseline was -0.73 (95% CI, -1.04 to -0.42; 8 studies). There was significant heterogeneity across studies with respect to both outcomes. Lower dosing frequency (P = .04), positive study (P = .03), longer duration of treatment (P < .001), and higher placebo dropout (P < .001) were associated with higher report of no pain. Response on Faces Pain Scales was greater in studies conducted in the Middle East (P = .002), in studies that did not report the randomization schedule (P = .02), and in studies with a higher percentage of females (P = .04).

CONCLUSIONS

Approximately 41% of children with abdominal pain-related functional gastrointestinal disorders improve on placebo. Several trial characteristics are correlated significantly with the proportion of patients with no pain on placebo and with the magnitude of the placebo response on Faces Pain Scales. These data could be valuable for the design of future studies.

The pediatric Rome IV criteria: what's new?

Functional gastrointestinal disorders (FGIDs) are common in children of all ages and comprise of a wide range of conditions related to the gastrointestinal tract that cannot be attributed to structural or biochemical abnormalities. FGIDs are diagnosed according to the symptom-based Rome criteria. Areas covered: In 2016, the revised pediatric Rome IV criteria were published, these revised criteria are discussed in this review article. For the youngest age group (neonates/toddlers), the criteria for infant colic have undergone the most notable revisions. The most prominent changes in Rome IV were made in the criteria for children/adolescents, with the definition of two new FGIDs (functional nausea and functional vomiting) and the restructuring of the criteria for functional abdominal pain disorders, including the definition of FGID subtypes for functional dyspepsia and irritable bowel syndrome. Expert commentary: Overall, the Rome IV have been refined and are expected to improve the process of diagnosing FGIDs in the pediatric population and to better facilitate the healthcare professional in distinguishing different clinical entities. These changes will likely benefit future research and clinical care.

Vitamin D status in pediatric irritable bowel syndrome

Importance

Irritable bowel syndrome (IBS) is associated with significant morbidity in children and adolescents, and the therapeutic efficacy of available treatment options is limited. The role of vitamin D supplementation in pediatric IBS is unclear as the vitamin D status of pediatric patients with IBS is unknown. Equally, the relationship of vitamin D status with psychosomatic symptoms in children and adolescents is unclear.

Aim

To characterize the vitamin D status of pediatric patients with IBS using a case-control study design.

Hypothesis

Serum 25-hydroxyvitamin D [25(OH)D] concentration will be similar between patients with IBS and controls.

Subjects and methods

A retrospective case-controlled study of 116 controls (age 14.6 ± 4.3 y), female (n = 67; 58%) and 55 subjects with IBS (age 16.5 ± 3.1y), female (n = 44; 80%). Overweight was defined as BMI of ≥85^th but <95^th percentile, and obesity as BMI ≥95^th percentile. Vitamin D deficiency was defined as 25(OH)D of <50 nmol/L, while seasons of vitamin D draw were categorized as summer, winter, spring, and fall. Major psychosomatic manifestations included in the analysis were depression, anxiety, and migraine.

Results

More than 50% of IBS subjects had vitamin D deficiency at a cut-off point of <50 nmol/L (53% vs. 27%, p = 0.001); and >90% of IBS subjects had vitamin D deficiency at a cut-off point of <75 nmol/L (93% vs. 75%, p = 0.006). IBS subjects had significantly lower mean 25(OH)D: 53.2 ± 15.8 nmol/L vs. 65.2 ± 28.0 nmol/L, p = 0.003; and albumin: 6.2 ± 0.6 vs. 6.5 ± 0.6 μmol/L, p = 0.0.01. IBS subjects with migraine had significantly lower mean 25(OH)D concentration compared to controls (p = 0.01). BMI z-score was similar between the controls and IBS subjects (0.5 ± 1.4 vs. 1.2 ± 2.9, p = 0.11).

Conclusions

Pediatric patients with IBS had significantly lower 25(OH)D concentration compared to controls despite having similar mean BMI values as controls. Only 7% of the children and adolescents with IBS were vitamin D sufficient, and >50% of the subjects with IBS had vitamin D deficiency. This is a much higher prevalence of vitamin D deficiency compared to IBD and other malabsorption syndromes. Monitoring for vitamin D deficiency should be part of the routine care for patients with IBS. Randomized control trials are warranted to determine the role of adjunctive vitamin D therapy in pediatric IBS.

Gastrointestinal Pharmacology

There is little evidence for most of the medications currently used to treat functional abdominal pain disorders (FAPDs) in children. Not only are there very few clinical trials, but also most have significant variability in the methods used and outcomes measured. Thus, the decision on the most appropriate pharmacological treatment is frequently based on adult studies or empirical data. In children, peppermint oil, trimebutine, and drotaverine have shown significant benefit compared with placebo, each of them in a single randomized clinical trial. A small study found that cyproheptadine was beneficial in the treatment of FAPDs in children. There are conflicting data regarding amitriptyline. While one small study found a significant benefit in quality of life compared with placebo, a large multicenter study found no benefit compared with placebo. The antidepressant, citalopram, failed to meet the primary outcomes in intention-to-treat and per-protocol analysis. Rifaximin has been shown to be efficacious in the treatment of adults with IBS. Those findings differ from studies in children where no benefit was found compared to placebo. To date, there are no placebo-controlled trials published on the use of linaclotide or lubiprostone in children. Alpha 2 delta ligands such as gabapentin and pregabalin are sometimes used in the care of this group of children, but no clinical trials are available in children with FAPDs. Similarly, novel drugs that have been approved for the care of irritable bowel with diarrhea in adults such as eluxadoline have yet to be studied in children.

CONCLUSIONS

Little data support the use of most medications commonly used to treat FAPDs in children. More randomized, placebo-controlled studies are needed to assess the efficacy of pharmacological interventions in the treatment of FAPDs in children.