Fecal bacterial microbiota in constipated patients before and after eight weeks of daily Bifidobacterium infantis 35624 administration.

INTRODUCTION AND AIM: In recent years, probiotics have been used in functional gastrointestinal disorders, including chronic constipation (CC). The effect of Bifidobacterium infantis strain 35624 on the gut microbiota of CC patients has not been previously studied. Our aim was to analyze the fecal microbiota of constipated patients, before and after consuming a single-strain probiotic (B. infantis strain 35624). MATERIALS AND METHODS: We used 16S rRNA gene high-throughput sequencing to analyze the fecal microbiota of female patients (n=13) with CC. Patients were instructed to ingest one capsule of Alflorex® (containing 1×109 CFUs/g B. infantis strain 35624) daily for eight weeks. Fecal samples were obtained at the baseline and end (final) of probiotic administration. RESULTS: Alpha diversity metrics did not differ between the baseline and final periods. The butyrate producer, Oscillospira, was the taxon most strongly correlated with amplicon sequence variants (R2=0.55, p<0.0001). Except for a few bacterial taxa, there were no significant differences in relative abundance between the baseline and final periods. Beta-diversity measures also showed limited evidence for the differences between the two time periods. CONCLUSIONS: The results suggest that the fecal bacterial microbiota remains stable in constipated women consuming a single-strain probiotic. Those findings may be helpful in better understanding probiotic functioning in patients with digestive disorders.

The PAC-SYM questionnaire for chronic constipation: defining the minimal important difference.

BACKGROUND: The Patient Assessment of Constipation-Symptoms (PAC-SYM) questionnaire is frequently used in clinical trials of constipation. However, the threshold for reduction in total PAC-SYM score used to define a clinical response on this 0-4 point scale has not undergone formal appraisal, and its relationship with clinical benefit as perceived by patients has not been defined. AIM: To determine the minimal important difference in PAC-SYM score, and the optimum cut-off value for defining responders. METHODS: The minimal important difference was estimated using data from six international phase 3/4, double-blind, randomised controlled trials of prucalopride in patients with chronic constipation (NCT01147926, NCT01424228, NCT01116206, NCT00485940, NCT00483886, NCT00488137), with anchor- and distribution-based approaches. Five appropriate patient-reported outcomes were selected as anchors. In addition, receiver operating characteristics (ROC) curve analyses were used to investigate responder discrimination for each anchor. RESULTS: Data from 2884 patients were included. Minimal important difference estimates ranged from -0.52 to -0.63 across the five anchors. Estimates were not affected by study location but were consistently lower for rectal symptoms than for abdominal and stool symptoms. Distribution-based estimates were considerably lower than anchor-based estimates. ROC curve analyses showed optimum cut-off scores for discriminating responders to be similar to anchor-based minimal important difference estimates. CONCLUSIONS: Anchor-based methods gave consistent results for the minimal important difference, at approximately -0.6, and this value was close to the ROC-determined optimal cut-off scores for responder discrimination. This value could be considered in clinical practice. A slightly more conservative threshold (eg -0.75) could be used in clinical trials to reduce the placebo response rate.

Pharmacoeconomic study of chronic constipation in a secondary care centre.

OBJECTIVE: The aim of this study was to measure any incremental costs or savings within the health system associated with the introduction of the new technology, prucalopride, for the management of chronic constipation. METHODOLOGY: The study design was based on a budget impact analysis conducted by the National Institute of Clinical Excellence (NICE). To validate the findings of the NICE costing template, a case series audit capturing real world data was used to determine the financial impact of adopting prucalopride in 40 women suffering with chronic constipation. This facilitated the application of local unit costs to the resources used and determined whether the use of prucalopride, as an alternative treatment to laxatives, resulted in a reduction in the use of secondary care resources. RESULTS: Patients were treated with an average of 2.6 laxatives in the baseline (laxatives only) scenario. The total medication costs in the baseline (laxatives only) and the new treatment (prucalopride) scenario amounted to €17,440.84 and €18,417.62, respectively. There was a significant reduction in the number of investigations and procedures in the 12 months after commencing prucalopride, with cost savings of €41,923.28 (€1,048.08 per patient per year) demonstrated. Input cost variables were adjusted as part of sensitivity analysis. CONCLUSION: This study validated the findings of the NICE costing template and suggests that the use of prucalopride for the treatment of chronic constipation in women refractory to laxatives has the potential to reduce secondary care resource use and hence led to cost savings.

Conducting multinational, cross-cultural research in the functional gastrointestinal disorders: issues and recommendations. A Rome Foundation working team report.

BACKGROUND: Cross-cultural, multinational research can advance the field of functional gastrointestinal disorders (FGIDs). Cross-cultural comparative research can make a significant contribution in areas such as epidemiology, genetics, psychosocial modulators, symptom reporting and interpretation, extra-intestinal co-morbidity, diagnosis and treatment, determinants of disease severity, health care utilisation, and health-related quality of life, all issues that can be affected by geographical region, culture, ethnicity and race. AIMS: To identify methodological challenges for cross-cultural, multinational research, and suggest possible solutions. METHODS: This report, which summarises the full report of a working team established by the Rome Foundation that is available on the Internet, reflects an effort by an international committee of FGID clinicians and researchers. It is based on comprehensive literature reviews and expert opinion. RESULTS: Cross-cultural, multinational research is important and feasible, but has barriers to successful implementation. This report contains recommendations for future research relating to study design, subject recruitment, availability of appropriate study instruments, translation and validation of study instruments, documenting confounders, statistical analyses and reporting of results. CONCLUSIONS: Advances in study design and methodology, as well as cross-cultural research competence, have not matched technological advancements. The development of multinational research networks and cross-cultural research collaboration is still in its early stages. This report is intended to be aspirational rather than prescriptive, so we present recommendations, not guidelines. We aim to raise awareness of these issues and to pose higher standards, but not to discourage investigators from doing what is feasible in any particular setting.

Disturbance of the gut microbiota in early-life selectively affects visceral pain in adulthood without impacting cognitive or anxiety-related behaviors in male rats.

Disruption of bacterial colonization during the early postnatal period is increasingly being linked to adverse health outcomes. Indeed, there is a growing appreciation that the gut microbiota plays a role in neurodevelopment. However, there is a paucity of information on the consequences of early-life manipulations of the gut microbiota on behavior. To this end we administered an antibiotic (vancomycin) from postnatal days 4-13 to male rat pups and assessed behavioral and physiological measures across all aspects of the brain-gut axis. In addition, we sought to confirm and expand the effects of early-life antibiotic treatment using a different antibiotic strategy (a cocktail of pimaricin, bacitracin, neomycin; orally) during the same time period in both female and male rat pups. Vancomycin significantly altered the microbiota, which was restored to control levels by 8 weeks of age. Notably, vancomycin-treated animals displayed visceral hypersensitivity in adulthood without any significant effect on anxiety responses as assessed in the elevated plus maze or open field tests. Moreover, cognitive performance in the Morris water maze was not affected by early-life dysbiosis. Immune and stress-related physiological responses were equally unaffected. The early-life antibiotic-induced visceral hypersensitivity was also observed in male rats given the antibiotic cocktail. Both treatments did not alter visceral pain perception in female rats. Changes in visceral pain perception in males were paralleled by distinct decreases in the transient receptor potential cation channel subfamily V member 1, the α-2A adrenergic receptor and cholecystokinin B receptor. In conclusion, a temporary disruption of the gut microbiota in early-life results in very specific and long-lasting changes in visceral sensitivity in male rats, a hallmark of stress-related functional disorders of the brain-gut axis such as irritable bowel disorder.

A four-country comparison of healthcare systems, implementation of diagnostic criteria, and treatment availability for functional gastrointestinal disorders: a report of the Rome Foundation Working Team on cross-cultural, multinational research.

BACKGROUND: Variations in healthcare provision around the world may impact how patients with functional gastrointestinal disorder (FGIDs) are investigated, diagnosed, and treated. However, these differences have not been reviewed. PURPOSES: The Multinational Working Team of the Rome Foundation, established to make recommendations on the conduct of multinational, cross-cultural research in FGIDs, identified seven key issues that are analyzed herein: (i) coverage afforded by different healthcare systems/providers; (ii) level of the healthcare system where patients with FGIDs are treated; (iii) extent/types of diagnostic procedures typically undertaken to diagnose FGIDs; (iv) physicians' familiarity with and implementation of the Rome diagnostic criteria in clinical practice; (v) range of medications approved for FGIDs and approval process for new agents; (vi) costs involved in treating FGIDs; and (vii) prevalence and role of complementary/alternative medicine (CAM) for FGIDs. Because it was not feasible to survey all countries around the world, we compared a selected number of countries based on their geographical and ethno-cultural diversity. Thus, we included Italy and South Korea as representative of nations with broad-based coverage of healthcare in the population and India and Mexico as newly industrialized countries where there may be limited provision of healthcare for substantial segments of the population. In light of the paucity of formal publications on these issues, we included additional sources from the medical literature as well as perspectives provided by local experts and the media. Finally, we provide future directions on healthcare issues that should be taken into account and implemented when conducting cross-cultural and multinational research in FGIDs.

A sustained hypothalamic-pituitary-adrenal axis response to acute psychosocial stress in irritable bowel syndrome.

BACKGROUND: Despite stress being considered a key factor in the pathophysiology of the functional gastrointestinal (GI) disorder irritable bowel syndrome (IBS), there is a paucity of information regarding the ability of IBS patients to respond to acute experimental stress. Insights into the stress response in IBS could open the way to novel therapeutic interventions. To this end, we assessed the response of a range of physiological and psychological parameters to the Trier Social Stress Test (TSST) in IBS. METHOD: Thirteen female patients with IBS and 15 healthy female age-matched control participants underwent a single exposure to the TSST. Salivary cortisol, salivary C-reactive protein (CRP), skin conductance level (SCL), GI symptoms, mood and self-reported stress were measured pre- and post-exposure to the TSST. RESULTS: The hypothalamic-pituitary-adrenal (HPA) axis response to the TSST was sustained in IBS, as shown by a greater total cortisol output throughout (p = 0.035) and higher cortisol levels measured by an area under the curve with respect to ground (AUCG) analysis (p = 0.044). In IBS patients, GI symptoms increased significantly during the recovery period following exposure to the TSST (p = 0.045). Salivary CRP and SCL activity showed significant changes in relation to stress but with no differential effect between experimental groups. CONCLUSIONS: Patients with IBS exhibit sustained HPA axis activity, and an increase in problematic GI symptoms in response to acute experimental psychosocial stress. These data pave the way for future interventional studies aimed at identifying novel therapeutic approaches to modulate the HPA axis and GI symptom response to acute psychosocial stress in IBS.

Cytokine imbalance in irritable bowel syndrome: a systematic review and meta-analysis.

BACKGROUND: Irritable bowel syndrome (IBS) is a functional gastrointestinal disorder of unknown etiology; although infection and inflammation have recently been considered as important etiologic agents. A recent meta-analysis showed correlations between cytokine [interleukin-10 (IL-10) and tumor necrosis factor (TNF)] gene polymorphisms and IBS; however, it is still unknown whether patients with IBS have different cytokine profiles compared to healthy population. METHODS: To determine the relationships between serum/plasma levels or mucosal expression of IL-10/TNF-α and IBS, we conducted a systematic review and meta-analysis based on case-control studies retrieved from PubMed and EMBASE search through August 2013. Standardized mean difference (SMD) was generated by using the inverse variance method. Heterogeneity was assessed based on I(2) values. KEY RESULTS: Serum/plasma levels of TNF-α tended to be higher in IBS vs controls (p = 0.09); this reached significance in IBS subtypes vs controls and in female patients with IBS. However, serum/plasma levels of IL-10 were not significantly different in IBS patients vs controls. Further analysis of serum/plasma IL-10 levels in IBS subtypes did not show any difference; however, analysis based on gender showed a significantly lower serum/plasma IL-10 levels in male patients with IBS vs male controls (p = 0.02). Colonic IL-10 mRNA had a significantly lower expression in IBS vs control (p = 0.001). CONCLUSIONS & INFERENCES: There is an imbalance of proinflammatory TNF-α, and anti-inflammatory IL-10, cytokines in IBS. Stratifying IBS patients based on cytokine profile may represent an opportunity for personalized treatment of this condition.

A dietary survey of patients with irritable bowel syndrome.

BACKGROUND: Food is one of the most commonly reported triggers of irritable bowel syndrome (IBS) symptoms. However, the role of diet in the aetiology and management of IBS has not been clearly established. The present study aimed to examine the dietary practices of Irish patients with IBS and to determine whether these practices increased their vulnerability to nutritional inadequacies. METHODS: A questionnaire was completed by 135 IBS patients on their perceptions of the role of diet in their symptoms and whether they restrict their diet according to the symptoms experienced. A similar questionnaire was used to investigate the perceptions of 111 healthy subjects to the gastrointestinal symptoms experienced on the consumption of food. RESULTS: Food was considered to cause or worsen their gastrointestinal symptoms in 89.6% of IBS patients compared to 55% of healthy subjects (P < 0.001). Cereal-based foods, predominantly bread or its components, were the most frequently cited (53.3%), and spicy foods (39.3%), vegetables and fatty foods (35.6% for both) also featured prominently. A significantly greater number of patients with IBS reported changing their diet to minimise symptoms compared to healthy controls (91.9% versus 45.5%, P < 0.001). In relation to whole food groups, milk products (9.6%), fruit (7.4%) and vegetables (5.2%) were those most commonly restricted, with only a small number of IBS patients seeking professional healthcare advice. CONCLUSIONS: The majority of IBS patients consider their symptoms to be related to food, and change their diet by limiting the foods that they perceive as problematic, with some restricting whole food groups. Few patients sought professional healthcare advice when implementing dietary change, possibly exposing a considerable number to an increased risk of nutritional deficiency.

Cognitive performance in irritable bowel syndrome: evidence of a stress-related impairment in visuospatial memory.

BACKGROUND: Central nervous system (CNS) dysfunction is a prominent feature of the functional gastrointestinal (GI) disorder, irritable bowel syndrome (IBS). However, the neurobiological and cognitive consequences of key pathophysiological features of IBS, such as stress-induced changes in hypothalamic-pituitary-adrenal (HPA)-axis functioning, is unknown. Our aim was to determine whether IBS is associated with cognitive impairment, independently of psychiatric co-morbidity, and whether cognitive performance is related to HPA-axis function. METHOD: A cross-sectional sample of 39 patients with IBS, a disease control group of 18 patients with Crohn's disease (CD) in clinical remission and 40 healthy age- and IQ-matched control participants were assessed using the Paired Associates Learning (PAL), Intra-Extra Dimensional Set Shift (IED) and Spatial Working Memory (SWM) tests from the Cambridge Neuropsychological Test Automated Battery (CANTAB) and a computerized Stroop test. HPA-axis function was determined by measuring the cortisol awakening response (CAR). RESULTS: IBS patients exhibited a subtle visuospatial memory deficit at the PAL six- pattern stage (p = 0.03), which remained after psychiatric co-morbidity was controlled for (p = 0.04). Morning cortisol levels were lower in IBS (p = 0.04) and significantly associated with visuospatial memory performance within IBS only (p = 0.02). CONCLUSIONS: For the first time, altered cognitive function on a hippocampal-mediated test of visuospatial memory, which was related to cortisol levels and independent of psychiatric co-morbidity, has been identified in IBS. Visuospatial memory impairment may be a common, but currently neglected, component of IBS. Further elucidation of the nature of this impairment may lead to a greater understanding of the underlying pathophysiology of IBS, and may provide novel therapeutic approaches.

Randomised clinical trial: daily pantoprazole magnesium 40 mg vs. esomeprazole 40 mg for gastro-oesophageal reflux disease, assessed by endoscopy and symptoms.

BACKGROUND: Pantoprazole magnesium (pantoprazole-Mg) may display extended inhibition of the proton pump with the potential for improved clinical efficacy in gastro-oesophageal reflux disease (GERD). AIM: To compare the efficacy of pantoprazole-Mg and esomeprazole in GERD. METHODS: Gastro-oesophageal reflux disease (Los Angeles grades A-D) patients were randomised to 4 weeks of treatment with pantoprazole-Mg (n = 290) or esomeprazole (n = 288), both 40 mg once daily, in this multicentre (14 Brazilian sites in 9 cities), double-blind study, with an additional 4 weeks' treatment in nonresponding patients. Severity of oesophagitis (at endoscopy) and GERD-related symptoms (ReQuest-GI) were assessed. The primary end point was the proportion of patients in complete remission (ReQuest-GI score <1.73 plus endoscopic healing) at week 4. RESULTS: Complete remission occurred in 61% of patients in each treatment group at 4 weeks (primary endpoint) and in 81% and 79% of patients in the pantoprazole-Mg and esomeprazole groups at 8 weeks, with no significant differences. Mucosal healing rates were high and not significantly different. At 8 weeks, symptom relief with pantoprazole-Mg was significantly greater than that with esomeprazole (91.6% vs. 86.0%, P = 0.0370) because of continued improvement in symptoms with pantoprazole-Mg from week 4 to week 8 (P = 0.0206). CONCLUSIONS: Pantoprazole-Mg 40 mg was at least as effective as esomeprazole 40 mg for complete remission and the mucosal healing rate was high. Symptom relief with pantoprazole-Mg continued to improve from 4 to 8 weeks and was greater than that with esomeprazole at week 8, suggesting an extended period of treatment effect (ClinicalTrials.gov identifier: NCT01132638).