American College of Gastroenterology Monograph on Management of Irritable Bowel Syndrome

INTRODUCTION Irritable bowel syndrome (IBS) is the most prevalent of the functional gastrointestinal disorders (FGIDs). Current estimates are that IBS affects up to 10–12% of adults in North America [1, 2]. Although it can affect all individuals regardless of age, creed, or gender, IBS is more common among women and is most commonly diagnosed in younger individuals (0.10 for the ÷2 test, was arbitrarily chosen to represent low levels of heterogeneity [29]. Review Manager version 5.3.5 (RevMan for Windows 2014, The Nordic Cochrane Centre, Copenhagen, Denmark) was used to generate Forest plots of pooled RRs and SMDs for primary and secondary outcomes with 95% CIs, as well as funnel plots. The latter were assessed for evidence of asymmetry, and therefore possible publication bias or other small study effects, using the Egger test [30], if there were sufficient (10 or more) eligible studies included in the meta-analysis, in line with published recommendations [31]. GRADEpro version 3.6 (GRADE working group 2004–2007) was used to grade the quality of the evidence. Consensus was reached using a consensus-oriented decision-making framework [32], culminating in a face-to-face meeting to discuss the evidence and reach a unanimous decision on the quality of evidence and strength of recommendation. EXERCISE, DIET AND DIETARY MANIPULATION Exercise We suggest exercise for overall symptom improvement in IBS patients. (Recommendation: weak; Quality of Evidence: very low) Exercise and physical fitness are key elements of maintaining physical and mental health [33, 34]. Studies from healthy volunteers and patients suggest that physical activity protects against gastrointestinal (GI) symptoms [35, 36], and bears an inverse relationship with colonic transit time [37]. Based upon these observations, it is reasonable to hypothesize that exercise might be beneficial to patients with IBS. To date, there have been few RCTs that have rigorously evaluated the benefits of exercise in IBS patients. Daley et al. invited 305 IBS patients to participate in a RCT that compared 12 weeks of an exercise intervention with usual care [38]. Fifty-six IBS patients (18%) agreed to participate. Quality of life (IBS-QOL) and IBS symptoms (Birmingham IBS symptoms questionnaire) were assessed before and after the interventions. Exercise led to statistically significant benefits for constipation (95% CI: -1.6 to -20.1) but not for other outcomes such as abdominal pain, diarrhea, total symptom score, or quality of life. In a second trial, Johannesson et al. randomized 102 IBS patients to a rigorous exercise program monitored by a physiotherapist or usual care for 12 weeks [39]. Seventy-five IBS patients completed the trial. IBS symptom severity scores improved to a greater degree in the exercise arm compared with the control arm (P = 0.003). The same authors reported long-term follow-up data (median follow-up 5.2 years) for 39 of the originally enrolled IBS patients [40]. Increases in physical activity and improvements in symptom scores compared with baseline were maintained at follow-up. Summary. Although it is clear that exercise offers general health benefits and, whenever possible, should be encouraged the Task Force did not feel that the weight or strength of available evidence justified a strong recommendation regarding exercise for IBS. Although encouraging, the Task Force feels that the current body of evidence should be viewed as hypothesis-generating, and in need of validation by methodologically rigorous, appropriately powered, RCTs. Diet and dietary manipulation for IBS We suggest a low diet for overall symptom improvement in IBS patients. (Recommendation: weak; Quality of very low) We suggest against a or diet based upon or test for overall symptom improvement in IBS patients. (Recommendation: weak; Quality of very low) The of IBS patients symptom or with a Although true food is in IBS food or are to of IBS patients in the of or their symptoms the publication of the last IBS Task Force evidence-based review in 2014 [4], there have been studies that have evaluated dietary therapies in IBS patients Although have been to IBS the body of evidence to two a diet low in and and and a We identified eligible RCTs that provided outcomes for a low diet versus an diet was an overall of the low diet in IBS symptoms with a of on a low diet of (95% to The NNT was (95% to of evidence from randomized controlled trials of pharmacological, psychological, and dietary therapies in irritable bowel to another recent systematic review analysis that all trials were subject to of the quality of the evidence was as very which related to from the small number of patients included in the trials, significant heterogeneity, and trials in IBS patients compared the low diet with an diet two with usual diet and one with a diet The trials that had of allocation and an dietary intervention in the control arm no statistically significant of a low diet = 95% = to with no heterogeneity between studies The results of these trials are more difficult to as they were not but trials two active dietary interventions. In each of these the low diet led to of IBS symptoms in of the patients. of the RCTs have evaluated the long-term efficacy or a low diet, or the diet that is after individual which should be with include impact on quality of life (e.g., and effects on the colonic which could effects on colonic health We identified two eligible trials a diet in patients with IBS were trials IBS patients that reported that their symptoms were controlled with a diet, but in had been rigorously were then randomized to have this diet with or This only the as a significant food group from the diet and then it the of a was no statistically significant impact on IBS symptoms in the versus diet = 95% to with significant heterogeneity between studies = P = RCT evaluated patients with IBS randomized to all for which they had levels of or a diet patients were asked to a similar number of but this was not based upon the test results This trial had an of were followed for 12 weeks and of in the active intervention arm a significant improvement in symptoms, compared with of in the diet This difference in rates was not statistically significant (P = The authors reported statistical in those that to their A more recent RCT testing to a true diet in IBS patients This study reported no difference in the of patients with of their IBS symptoms (P = or quality of life (P = after weeks However, there was a significantly greater in IBS global improvement with the true diet (P = after Summary. therapies for IBS are of interest to and the body of to the low The available evidence a possible for overall IBS symptoms in of are data for a diet or based upon or there are or no data that the efficacy, or of dietary therapies for IBS. IBS We for overall symptom improvement in IBS patients. (Recommendation: Quality of We psyllium, but not wheat bran, for overall symptom improvement in IBS patients. (Recommendation: Quality of The updated systematic review and meta-analysis on in IBS performed for this identified patients Only one trial was at low of bias was a statistically significant in of compared with placebo of IBS not = 95% to was no significant heterogeneity between results = P = studies used in a total of patients studies in a total of patients and the studies used or had no significant on treatment of IBS of IBS not = 95% to but was effective in treating IBS = 95% to The NNT with was (95% to Data on overall adverse events were only provided by trials These trials evaluated patients. A total of of patients reported adverse events, compared with of in the placebo = 95% to were data from individual studies to assess adverse events according to of Summary. an evidence-based treatment for IBS. pain and bloating in IBS, and no evidence for The low and of significant effects a reasonable therapy for IBS patients and, in with the quality of is the of a strong recommendation. The to stool and for the of in patients with the evidence to this is from AND and We suggest against the of and for overall symptom improvement in IBS patients. (Recommendation: weak; Quality of very low) The that in the might be relevant to IBS from that symptoms of IBS developed after an that small symptoms from IBS and that the colonic is altered in IBS In addition, IBS symptoms (e.g., and have been with These have also led to the of prebiotics, probiotics, and synbiotics, as well as in the treatment of IBS. are food or dietary that in in the activity of the have been defined as when in a health on the which are also food or dietary are a of and that to the and of beneficial The monograph identified no trials of in IBS [4]. The updated search identified one RCT In this study patients with were recruited, and randomized to either from or placebo for This trial was at of bias due to to the used to conceal treatment allocation. global IBS symptoms abdominal pain were reported as a outcome by the abdominal pain scores at weeks were significantly with the the placebo P scores were also significantly improved with P = Data on adverse events were regard to synbiotics, no new RCTs were identified since the last version of the monograph [4], but there were two studies that recruited a total of patients The first was a RCT in patients with IBS, and which used a of and with in a and for 12 Only this trial reported were of patients to with symptoms, compared with of to control therapy (P The second in used in with for weeks in patients. This trial was at of bias due to to the used to conceal treatment allocation. trials assessed IBS symptoms on a continuous in patients. both trials were there was no statistically significant of in symptoms, due to significant heterogeneity between studies = 95% to = P = In both studies adverse events were and no significant events in either treatment We suggest probiotics, as a to global symptoms, as well as bloating and in IBS patients. (Recommendation: weak; Quality of low) the monograph a total of new trials were identified in there were RCTs patients. trials were at low of with the being were RCTs patients that outcomes as a were statistically