A Diet Low in Red and Processed Meat Does Not Reduce Rate of Crohn's Disease Flares.

BACKGROUND & AIMS: Diet may be an important factor in the progression of Crohn's disease (CD). We performed a randomized controlled trial to determine whether reduced consumption of red and processed meats decreases the risk of symptomatic relapse of CD, analyzing results from the Food and Crohn's Disease Exacerbation Study (FACES) trial. METHODS: Adults with CD were recruited into the FACES trial from IBD Partners, an Internet-based cohort of patients with inflammatory bowel disease, from November 2013 through June 2015. Individuals who were in remission (CD activity index [sCDAI] scores of ≤150), had completed a biannual survey, and reported consumption of red meat at least once weekly were randomly assigned to groups that consumed a minimum of 2 servings/week of red or processed meat (high meat, n = 118) or not more than 1 serving per month (low meat, n = 96) for 49 weeks. The primary outcome was relapse of CD, defined as increase in sCDAI score by ≥70 points and to >150 or a need for CD surgery or new CD medication. A secondary outcome, moderate or severe relapse, was based on an increase in sCDAI to >219. RESULTS: During the trial, the high-meat groups reported consumption of 2 or more servings of red or processed meat during 98.5% of observed weeks compared with 18.8% of weeks for the low-meat group. Any and moderate to severe relapse occurred in 62% of participants in the high-meat group and 42% of participants in the low-meat group. There were no significant differences in time to any (P = .61) or moderate/severe (P = .50) relapse. CONCLUSIONS: In an analysis of data from the FACES trial, we found that among patients with CD in remission, level of red and processed meat consumption was not associated with time to symptomatic relapse. ClinicalTrials.gov, Number: NCT0192673.

Variation Among Patients With Crohn's Disease in Benefit vs Risk Preferences and Remission Time Equivalents.

BACKGROUND & AIMS: Patients with Crohn's disease (CD) must make decisions about their treatment. We aimed to quantify patients' preferences for different treatment outcomes and adverse events. We also evaluated the effects of latent class heterogeneity on these preferences. METHODS: An online stated-preference survey was completed by 812 individuals with CD in the Crohn's and Colitis Foundation Partners cohort (IBD Partners). Patients were given information on symptoms and severity of active disease; duration of therapy with corticosteroids; and risks of serious infection, cancer and surgery. Patients were asked to assume that their treatment was not working and to choose an alternative therapy. The primary outcome was remission-time equivalents (RTE) of a given duration of symptom severity or treatment-related risk. Latent class choice models identified groups of patients with dominant treatment-outcome preferences and associated patient characteristics with these groups. RESULTS: Latent class analysis demonstrated 3 distinct groups of survey responders whose choices were strongly influenced by avoidance of active symptoms (61%), avoidance of corticosteroid use (25%), or avoidance of risks of cancer, infection or surgery (14%) when choosing a therapy. Class membership was correlated with age, sex, mean short CD activity index score and corticosteroid avoidance. RTEs in each latent class differed significantly from the mean RTEs for the overall sample, although the symptom-avoidant class most closely approximated the overall sample. CONCLUSIONS: In an online survey of patients with CD, we found substantial heterogeneity in preference for medication efficacy and risk of harm. Physicians and regulators should therefore not assume that all patients have mean-value preferences-this could result in significant differences in health-technology assessment models.

Comparative metabolomics in vegans and omnivores reveal constraints on diet-dependent gut microbiota metabolite production.

OBJECTIVE: The consumption of an agrarian diet is associated with a reduced risk for many diseases associated with a 'Westernised' lifestyle. Studies suggest that diet affects the gut microbiota, which subsequently influences the metabolome, thereby connecting diet, microbiota and health. However, the degree to which diet influences the composition of the gut microbiota is controversial. Murine models and studies comparing the gut microbiota in humans residing in agrarian versus Western societies suggest that the influence is large. To separate global environmental influences from dietary influences, we characterised the gut microbiota and the host metabolome of individuals consuming an agrarian diet in Western society. DESIGN AND RESULTS: Using 16S rRNA-tagged sequencing as well as plasma and urinary metabolomic platforms, we compared measures of dietary intake, gut microbiota composition and the plasma metabolome between healthy human vegans and omnivores, sampled in an urban USA environment. Plasma metabolome of vegans differed markedly from omnivores but the gut microbiota was surprisingly similar. Unlike prior studies of individuals living in agrarian societies, higher consumption of fermentable substrate in vegans was not associated with higher levels of faecal short chain fatty acids, a finding confirmed in a 10-day controlled feeding experiment. Similarly, the proportion of vegans capable of producing equol, a soy-based gut microbiota metabolite, was less than that was reported in Asian societies despite the high consumption of soy-based products. CONCLUSIONS: Evidently, residence in globally distinct societies helps determine the composition of the gut microbiota that, in turn, influences the production of diet-dependent gut microbial metabolites.

Inflammatory Bowel Disease Patients' Willingness to Accept Medication Risk to Avoid Future Disease Relapse.

OBJECTIVES: Biomarkers, endoscopy and imaging tests can identify patients at increased risk for early recurrence of symptomatic inflammatory bowel disease (IBD). However, patients may be unwilling to accept additional medical therapy risks related to therapy escalation to avoid a future disease relapse. We sought to quantify IBD patients' willingness to accept medication risk to avoid future disease relapse. METHODS: We conducted a discrete-choice experiment among 202 patients with IBD who were offered choices of therapies with varying risks of lymphoma and infection, and varying time to next IBD relapse. Random parameters logit was used to estimate patients' willingness to accept tradeoffs among treatment features in selecting medication therapy to avoid future disease relapse. RESULTS: To avoid a disease relapse over the next 5 years, IBD patients were willing to accept an average of a 28% chance of a serious infection; and an average of 1.8% chance of developing lymphoma. These results did not significantly change when patients were offered 10 years until their next disease relapse, but were lower (11 and 0.7%, respectively) when offered 1.5 years until the next disease relapse. Patients with active disease symptoms were significantly less willing to accept medication risk for time in remission. CONCLUSIONS: IBD patients are willing to accept high levels of lymphoma and serious infection risk to maintain disease remission. These preferences are congruent with the treatment paradigms emphasizing mucosal healing and early aggressive therapy and highlight patients' strong preferences for therapies resulting in durable remission of at least 5 years.

Mesalamine dose escalation reduces fecal calprotectin in patients with quiescent ulcerative colitis.

BACKGROUND & AIMS: Among patients with quiescent ulcerative colitis (UC), lower fecal concentrations of calprotectin are associated with lower rates of relapse. We performed an open-label, randomized controlled trial to investigate whether increasing doses of mesalamine reduce concentrations of fecal calprotectin (FC) in patients with quiescent UC. METHODS: We screened 119 patients with UC in remission on the basis of Simple Clinical Colitis Activity Index scores, FC >50 µg/g, and intake of no more than 3 g/day mesalamine. Participants taking mesalamine formulations other than multimatrix mesalamine were switched to multimatrix mesalamine (2.4 g/day) for 6 weeks; 52 participants were then randomly assigned (1:1) to a group that continued its current dose of mesalamine (controls, n = 26) or a group that increased its dose by 2.4 g/day for 6 weeks (n = 26). The primary outcome was continued remission with FC <50 µg/g. Secondary outcomes were continued remission with FC <100 µg/g or <200 µg/g (among patients with pre-randomization values above these levels). RESULTS: The primary outcome was achieved by 3.8% of controls and 26.9% of the dose escalation group (P = .0496). More patients in the dose escalation group reduced FC to below 100 µg/g (P = .04) and 200 µg/g (P = .005). Among the patients who were still in remission after the randomization phase, clinical relapse occurred sooner in patients with FC >200 µg/g compared with those with FC <200 µg/g (P = .01). CONCLUSIONS: Among patients with quiescent UC and increased levels of FC, increasing the dose of mesalamine by 2.4 g/day reduced fecal concentrations of calprotectin to those associated with lower rates of relapse. Clinicaltrials.gov number: NCT00652145.

Endoscopic and Histological Assessment, Correlation, and Relapse in Clinically Quiescent Ulcerative Colitis (MARQUEE).

OBJECTIVE: It is difficult to predict relapse in quiescent ulcerative colitis (UC), but newer endoscopic and histological indices could improve this. This study aimed to determine in UC patients in clinical remission (1) the prevalence of active endoscopic and histological disease; (2) the correlation between endoscopic and histological scores; and (3) the predictive power of these scores for clinical relapse. DESIGN: This multicenter prospective cohort study conducted by the Crohn's and Colitis Foundation Clinical Research Alliance included 100 adults with UC in clinical remission undergoing surveillance colonoscopy for dysplasia. Endoscopic activity was assessed using the Mayo endoscopic score (MES), ulcerative colitis endoscopic index of severity (UCEIS), and ulcerative colitis colonoscopic index of severity (UCCIS). Histology was assessed with the Riley index subcomponents, total Riley score, and basal plasmacytosis. RESULTS: Only 5% of patients had an MES of 0, whereas 38% had a score of 2 to 3; using the UCEIS, the majority of patients had at least mild activity, and 15% had more severe activity. Many patients also had evidence of histological disease activity. The correlations among endoscopic indices, histological subcomponents, and total score were low; the highest correlations occurred with the subcomponent architectural irregularity (ρ = 0.43-0.44), total Riley score (ρ = 0.35-0.37), and basal plasmacytosis (ρ = 0.35-0.36). Nineteen patients relapsed clinically over 1 year, with the subcomponent architectural irregularity being the most predictive factor (P = 0.0076). CONCLUSIONS: This multicenter prospective study found a high prevalence of both endoscopic and histological disease activity in clinically quiescent UC. The correlations between endoscopy and histology were low, and the power to predict clinical relapse was moderate.

Comparative Effectiveness of Nutritional and Biological Therapy in North American Children with Active Crohn's Disease.

BACKGROUND: Therapeutic targets in pediatric Crohn's disease include symptoms, quality of life (QOL), and mucosal healing. Although partial enteral nutrition (PEN), exclusive enteral nutritional (EEN), and anti-tumor necrosis factor alpha (anti-TNF) therapy all improve symptoms, the comparative effectiveness of these approaches to improve QOL and achieve mucosal healing has not been assessed prospectively. METHODS: In a prospective study of children initiating PEN, EEN, or anti-TNF therapy for Crohn's disease, we compared clinical outcomes using the Pediatric Crohn's Disease Activity Index (PCDAI), QOL (IMPACT score), and mucosal healing as estimated by fecal calprotectin (FCP). PCDAI, IMPACT, FCP, and diet (prompted 24-h recall) were measured at baseline and after 8 weeks of therapy. RESULTS: We enrolled 90 children with active Crohn's disease (PCDAI, 33.7 ± 13.7; and FCP, 976 ± 754), of whom 52 were treated with anti-TNF, 22 with EEN, and 16 with PEN plus ad lib diet. Clinical response (PCDAI reduction ≥15 or final PCDAI ≤10) was achieved by 64% on PEN, 88% EEN, and 84% anti-TNF (test for trend P = 0.08). FCP ≤250 µg/g was achieved with PEN in 14%, EEN 45%, and anti-TNF 62% (test for trend P = 0.001). Improvement in overall QOL was not statistically significantly different between the 3 groups (P = 0.86). However, QOL improvement was the greatest with EEN in the body image (P = 0.03) domain and with anti-TNF in the emotional domain (P = 0.04). CONCLUSIONS: Although PEN improved clinical symptoms, EEN and anti-TNF were more effective for decreasing mucosal inflammation and improving specific aspects of QOL.

Inflammation, Antibiotics, and Diet as Environmental Stressors of the Gut Microbiome in Pediatric Crohn's Disease.

Abnormal composition of intestinal bacteria--"dysbiosis"-is characteristic of Crohn's disease. Disease treatments include dietary changes and immunosuppressive anti-TNFα antibodies as well as ancillary antibiotic therapy, but their effects on microbiota composition are undetermined. Using shotgun metagenomic sequencing, we analyzed fecal samples from a prospective cohort of pediatric Crohn's disease patients starting therapy with enteral nutrition or anti-TNFα antibodies and reveal the full complement and dynamics of bacteria, fungi, archaea, and viruses during treatment. Bacterial community membership was associated independently with intestinal inflammation, antibiotic use, and therapy. Antibiotic exposure was associated with increased dysbiosis, whereas dysbiosis decreased with reduced intestinal inflammation. Fungal proportions increased with disease and antibiotic use. Dietary therapy had independent and rapid effects on microbiota composition distinct from other stressor-induced changes and effectively reduced inflammation. These findings reveal that dysbiosis results from independent effects of inflammation, diet, and antibiotics and shed light on Crohn disease treatments.

Linking long-term dietary patterns with gut microbial enterotypes.

Diet strongly affects human health, partly by modulating gut microbiome composition. We used diet inventories and 16S rDNA sequencing to characterize fecal samples from 98 individuals. Fecal communities clustered into enterotypes distinguished primarily by levels of Bacteroides and Prevotella. Enterotypes were strongly associated with long-term diets, particularly protein and animal fat (Bacteroides) versus carbohydrates (Prevotella). A controlled-feeding study of 10 subjects showed that microbiome composition changed detectably within 24 hours of initiating a high-fat/low-fiber or low-fat/high-fiber diet, but that enterotype identity remained stable during the 10-day study. Thus, alternative enterotype states are associated with long-term diet.