Eamonn M. M. Quigley

ACCF/ACG/AHA 2008 expert consensus document on reducing the gastrointestinal risks of antiplatelet therapy and NSAID use: A report of the American College of Cardiology Foundation Task Force on clinical expert consensus documents

ACCF TASK FORCE MEMBERS Robert A. Harrington, MD, FACC, Chair; Eric R. Bates, MD, FACC; Charles R. Bridges, MD, MPH, FACC; Mark J. Eisenberg, MD, MPH, FACC; Victor A. Ferrari, MD, FACC; Mark A. Hlatky, MD, FACC; Sanjay Kaul, MBBS, FACC; Jonathan R. Lindner, MD, FACC‡; David J. Moliterno, MD, FACC; Debabrata Mukherjee, MD, FACC; Richard S. Schofield, MD, FACC‡; Robert S. Rosenson, MD, FACC; James H. Stein, MD, FACC; Howard H. Weitz, MD, FACC; Deborah J. Wesley, RN, BSN

Efficacy of an encapsulated probiotic Bifidobacterium infantis 35624 in women with irritable bowel syndrome.

BACKGROUND:Probiotic bacteria exhibit a variety of properties, including immunomodulatory activity, which are unique to a particular strain. Thus, not all species will necessarily have the same therapeutic potential in a particular condition. We have preliminary evidence that Bifidobacterium infantis 35624 may have utility in irritable bowel syndrome (IBS).OBJECTIVES:This study was designed to confirm the efficacy of the probiotic bacteria B. infantis 35624 in a large-scale, multicenter, clinical trial of women with IBS. A second objective of the study was to determine the optimal dosage of probiotic for administration in an encapsulated formulation.METHODS:After a 2-wk baseline, 362 primary care IBS patients, with any bowel habit subtype, were randomized to either placebo or freeze-dried, encapsulated B. infantis at a dose of 1 × 106, 1 × 108, or 1 × 1010, cfu/mL for 4 wk. IBS symptoms were monitored daily and scored on to a 6-point Likert scale with the primary outcome variable being abdominal pain or discomfort. A composite symptom score, the subjects global assessment of IBS symptom relief, and measures of quality of life (using the IBS-QOL instrument) were also recorded.RESULTS:B. infantis 35624 at a dose of 1 × 108 cfu was significantly superior to placebo and all other bifidobacterium doses for the primary efficacy variable of abdominal pain as well as the composite score and scores for bloating, bowel dysfunction, incomplete evacuation, straining, and the passage of gas at the end of the 4-wk study. The improvement in global symptom assessment exceeded placebo by more than 20% (p < 0.02). Two other doses of probiotic (1 × 106 and 1 × 1010) were not significantly different from placebo; of these, the 1 × 1010 dose was associated with significant formulation problems. No significant adverse events were recorded.CONCLUSIONS:B. infantis 35624 is a probiotic that specifically relieves many of the symptoms of IBS. At a dosage level of 1 × 108 cfu, it can be delivered by a capsule making it stable, convenient to administer, and amenable to widespread use. The lack of benefits observed with the other dosage levels of the probiotic highlight the need for clinical data in the final dosage form and dose of probiotic before these products should be used in practice.

Early Life Stress Alters Behavior, Immunity, and Microbiota in Rats: Implications for Irritable Bowel Syndrome and Psychiatric Illnesses

BACKGROUND Adverse early life events are associated with a maladaptive stress response system and might increase the vulnerability to disease in later life. Several disorders have been associated with early life stress, ranging from depression to irritable bowel syndrome. This makes the identification of the neurobiological substrates that are affected by adverse experiences in early life invaluable. METHODS The purpose of this study was to assess the effect of early life stress on the brain-gut axis. Male rat pups were stressed by separating them from their mothers for 3 hours daily between postnatal days 2-12. The control group was left undisturbed with their mothers. Behavior, immune response, stress sensitivity, visceral sensation, and fecal microbiota were analyzed. RESULTS The early life stress increased the number of fecal boli in response to a novel stress. Plasma corticosterone was increased in the maternally separated animals. An increase in the systemic immune response was noted in the stressed animals after an in vitro lipopolysaccharide challenge. Increased visceral sensation was seen in the stressed group. There was an alteration of the fecal microbiota when compared with the control group. CONCLUSIONS These results show that this form of early life stress results in an altered brain-gut axis and is therefore an important model for investigating potential mechanistic insights into stress-related disorders including depression and IBS.

The efficacy of probiotics in the treatment of irritable bowel syndrome: a systematic review

Introduction Probiotics may benefit irritable bowel syndrome (IBS) symptoms, but randomised controlled trials (RCTs) have been conflicting; therefore a systematic review was conducted. Methods MEDLINE (1966 to May 2008), EMBASE (1988 to May 2008) and the Cochrane Controlled Trials Register (2008) electronic databases were searched, as were abstracts from DDW (Digestive Diseases Week) and UEGW (United European Gastroenterology Week), and authors were contacted for extra information. Only parallel group RCTs with at least 1 week of treatment comparing probiotics with placebo or no treatment in adults with IBS according to any acceptable definition were included. Studies had to provide improvement in abdominal pain or global IBS symptoms as an outcome. Eligibility assessment and data extraction were performed by two independent researchers. Data were synthesised using relative risk (RR) of symptoms not improving for dichotomous data and standardised mean difference (SMD) for continuous data using random effects models. Results 19 RCTs (18 papers) in 1650 patients with IBS were identified. Trial quality was generally good, with nine reporting adequate methods of randomisation and six a method of concealment of allocation. There were 10 RCTs involving 918 patients providing outcomes as a dichotomous variable. Probiotics were statistically significantly better than placebo (RR of IBS not improving=0.71; 95% CI 0.57 to 0.88) with a number needed to treat (NNT)=4 (95% CI 3 to 12.5). There was significant heterogeneity (χ2=28.3, p=0.001, I2=68%) and possible funnel plot asymmetry. Fifteen trials assessing 1351 patients reported on improvement in IBS score as a continuous outcome (SMD=−0.34; 95% CI −0.60 to −0.07). There was statistically significant heterogeneity (χ2=67.04, p<0.001, I2=79%), but this was explained by one outlying trial. Conclusion Probiotics appear to be efficacious in IBS, but the magnitude of benefit and the most effective species and strain are uncertain.

Efficacy of Antidepressants and Psychological Therapies in Irritable Bowel Syndrome: Systematic Review and Meta-analysis.

Objective: Irritable bowel syndrome (IBS) is a chronic functional gastrointestinal disorder. Evidence for treatment of the condition with antidepressants and psychological therapies is conflicting. Design: Systematic review and meta-analysis of randomised controlled trials (RCTs). MEDLINE, EMBASE and the Cochrane Controlled Trials Register were searched (up to May 2008). Setting: RCTs based in primary, secondary and tertiary care. Patients: Adults with IBS. Interventions: Antidepressants versus placebo, and psychological therapies versus control therapy or “usual management”. Main outcome measures: Dichotomous symptom data were pooled to obtain a relative risk (RR) of remaining symptomatic after therapy, with a 95% confidence interval (CI). The number needed to treat (NNT) was calculated from the reciprocal of the risk difference. Results: The search strategy identified 571 citations. Thirty-two RCTs were eligible for inclusion: 19 compared psychological therapies with control therapy or “usual management”, 12 compared antidepressants with placebo, and one compared both psychological therapy and antidepressants with placebo. Study quality was generally good for antidepressant but poor for psychological therapy trials. The RR of IBS symptoms persisting with antidepressants versus placebo was 0.66 (95% CI, 0.57 to 0.78), with similar treatment effects for both tricyclic antidepressants and selective serotonin reuptake inhibitors. The RR of symptoms persisting with psychological therapies was 0.67 (95% CI, 0.57 to 0.79). The NNT was 4 for both interventions. Conclusions: Antidepressants are effective in the treatment of IBS. There is less high-quality evidence for routine use of psychological therapies in IBS, but available data suggest these may be of comparable efficacy.

Composition and energy harvesting capacity of the gut microbiota: relationship to diet, obesity and time in mouse models

Background and Aims Increased efficiency of energy harvest, due to alterations in the gut microbiota (increased Firmicutes and decreased Bacteroidetes), has been implicated in obesity in mice and humans. However, a causal relationship is unproven and contributory variables include diet, genetics and age. Therefore, we explored the effect of a high-fat (HF) diet and genetically determined obesity (ob/ob) for changes in microbiota and energy harvesting capacity over time. Methods Seven-week-old male ob/ob mice were fed a low-fat diet and wild-type mice were fed either a low-fat diet or a HF-diet for 8 weeks (n=8/group). They were assessed at 7, 11 and 15 weeks of age for: fat and lean body mass (by NMR); faecal and caecal short-chain fatty acids (SCFA, by gas chromatography); faecal energy content (by bomb calorimetry) and microbial composition (by metagenomic pyrosequencing). Results A progressive increase in Firmicutes was confirmed in both HF-fed and ob/ob mice reaching statistical significance in the former, but this phylum was unchanged over time in the lean controls. Reductions in Bacteroidetes were also found in ob/ob mice. However, changes in the microbiota were dissociated from markers of energy harvest. Thus, although the faecal energy in the ob/ob mice was significantly decreased at 7 weeks, and caecal SCFA increased, these did not persist and faecal acetate diminished over time in both ob/ob and HF-fed mice, but not in lean controls. Furthermore, the proportion of the major phyla did not correlate with energy harvest markers. Conclusion The relationship between the microbial composition and energy harvesting capacity is more complex than previously considered. While compositional changes in the faecal microbiota were confirmed, this was primarily a feature of high-fat feeding rather than genetically induced obesity. In addition, changes in the proportions of the major phyla were unrelated to markers of energy harvest which changed over time. The possibility of microbial adaptation to diet and time should be considered in future studies.

Guidelines for Prevention of NSAID-Related Ulcer Complications

Guidelines for clinical practice are intended to indicate preferred approaches to medical problems as established by scientifically valid research. Double-blind, placebo-controlled studies are preferable, but compassionate use reports and expert review articles are used in a thorough review of the literature conducted through Medline with the National Library of Medicine. Only when data that will not withstand objective scrutiny are available is a recommendation identified as a consensus of experts. Guidelines are applicable to all physicians who address the subject, without regard to specialty training or interests, and are intended to indicate the preferable, but not necessarily the only, acceptable approach to a specific problem. Guidelines are intended to be flexible and must be distinguished from standards of care, which are inflexible and rarely violated. Given the wide range of specifics in any health-care problem, the physician must always choose the course best suited to the individual patient and the variables in existence at the moment of decision. These guidelines were developed under the auspices of the American College of Gastroenterology by a committee of experts in the field, reviewed by its Practice Parameters Committee, and approved by the Board of Trustees. The recommendations of these guidelines are therefore considered valid at the time of production based on the data available. New developments in medical research and practice pertinent to each guideline will be reviewed at an established time and indicated at publication to assure continued validity. Owing to the volume of new data on the subject of non-steroidal anti-inflammatory drug (NSAID)-related injury to the upper gastrointestinal tract, i.e., the advent of cyclooxygenase (COX)-2 inhibitors, new data on interactions between these agents, as well as traditional NSAIDs, with aspirin and H. pylori, it was elected by the Committee to confine these guidelines to upper gastrointestinal (GI) injury and to leave post-duodenal injury as the subject of a separate guideline.

Assessment of gastric emptying using a low fat meal: establishment of international control values.

OBJECTIVE:The diagnosis of gastroparesis implies delayed gastric emptying. The diagnostic gold standard is scintigraphy, but techniques and measured endpoints vary widely among institutions. In this study, a simplified scintigraphic measurement of gastric emptying was compared to conventional gastric scintigraphic techniques and normal gastric emptying values defined in healthy subjects.METHODS:In 123 volunteers (aged 19–73 yr, 60 women and 63 men) from 11 centers, scintigraphy was used to assess gastric emptying of a 99Tc-labeled low fat meal (egg substitute) and percent intragastric residual contents 60, 120, and 240 min after completion of the meal. In 42 subjects, additional measurements were taken every 10 min for 1 h. In 20 subjects, gastric emptying of a 99Tc-labeled liver meal was compared with that of the 99Tc-labeled low fat meal.RESULTS:Median values (95th percentile) for percent gastric retention at 60, 120, and 240 min were 69% (90%), 24% (60%) and 1.2% (10%) respectively. A power exponential model yielded similar emptying curves and estimated T50 when using images only taken at 1, 2 and 4 h, or with imaging taken every 10 min. Gastric emptying was initially more rapid in men but was comparable in men and women at 4 h; it was faster in older subjects (p < 0.05) but was independent of body mass index.CONCLUSIONS:This multicenter study provides gastric emptying values in healthy subjects based on data obtained using a large sample size and consistent meal and methodology. Gastric retention of >10% at 4 h is indicative of delayed emptying, a value comparable to those provided by more intensive scanning approaches. Gastric emptying of a low fat meal is initially faster in men but is comparable in women at 4 h; it is also faster in older individuals but is independent of body mass.

Probiotics: from myth to reality. Demonstration of functionality in animal models of disease and in human clinical trials

The enteric flora comprise approximately 95% of the total number of cells in the human body and are capable of eliciting immune responses while also protecting against microbial pathogens. However, the resident bacterial flora of the gastrointestinal tract (GIT) may also be implicated in the pathogenesis of several chronic conditions such as inflammatory bowel disease (IBD). The University College Cork-based Probiotic Research Group has successfully isolated and identified lactic acid bacteria (LAB) which exhibit beneficial probiotic traits. These characteristics include the demonstration of bile tolerance; acid resistance; adherence to host epithelial tissue; and in vitro antagonism of potentially-pathogenic micro-organisms or those which have been implicated in promoting inflammation. The primary objective of this report is to describe the strategy adopted for the selection of potentially effective probiotic bacteria. The study further describes the evaluation of two m embers of the resulting panel of micro-organisms (Lactobacillus salivarius subsp. salivarius UCC118 and Bifidobacterium longum infantis 35624) under in vitro conditions and throughout in vivo murine and human feeding trials. Specifically, an initial feeding study completed in Balb/c mice focused upon (i) effective delivery of the probiotic micro-organisms to the GIT and evaluation of the ability of the introduced strains to survive transit through, and possibly colonise, the murine GIT; (ii) accepting the complexity of the hostile GIT and faecal environments, development of a method of enumerating the introduced bacterial strains using conventional microbiological techniques; and (iii) assessment of the effects of administered bacterial strains on the numbers of specific recoverable indigenous bacteria in the murine GIT and faeces. Additional research, exploiting the availability of murine models of inflammatory bowel disease, demonstrated the beneficial effects of administering probi otic combinations of Lactobacillus salivarius UCC118 and Bifidobacterium longum infantis 35624 in prevention of illness-related weight loss. A further ethically-approved feeding trial, successfully conducted in 80 healthy volunteers, demonstrated that yoghurt can be used as a vehicle for delivery of Lactobacillus salivarius strain UCC118 to the human GIT with considerable efficacy in influencing gut flora and colonisation.

An irritable bowel syndrome subtype defined by species-specific alterations in faecal microbiota

Background and aims Irritable bowel syndrome (IBS) is a common functional gastrointestinal disorder that may be triggered by enteric pathogens and has also been linked to alterations in the microbiota and the host immune response. The authors performed a detailed analysis of the faecal microbiota in IBS and control subjects and correlated the findings with key clinical and physiological parameters. Design The authors used pyrosequencing to determine faecal microbiota composition in 37 IBS patients (mean age 37 years; 26 female subjects; 15 diarrhoea-predominant IBS, 10 constipation-predominant IBS and 12 alternating-type IBS) and 20 age- and gender-matched controls. Gastrointestinal and psychological symptom severity and quality of life were evaluated with validated questionnaires and colonic transit time and rectal sensitivity were measured. Results Associations detected between microbiota composition and clinical or physiological phenotypes included microbial signatures associated with colonic transit and levels of clinically significant depression in the disease. Clustering by microbiota composition revealed subgroups of IBS patients, one of which (n=15) showed normal-like microbiota composition compared with healthy controls. The other IBS samples (n=22) were defined by large microbiota-wide changes characterised by an increase of Firmicutes-associated taxa and a depletion of Bacteroidetes-related taxa. Conclusions Detailed microbiota analysis of a well-characterised cohort of IBS patients identified several clear associations with clinical data and a distinct subset of IBS patients with alterations in their microbiota that did not correspond to IBS subtypes, as defined by the Rome II criteria.