Association Between Celiac Disease and Irritable Bowel Syndrome: A Nationwide Cohort Study.

BACKGROUND & AIMS: The aim of this study was to determine the risk of irritable bowel syndrome (IBS) diagnosis in patients with celiac disease (CD) compared with general population comparators. METHODS: Using Swedish histopathology and register-based data, we identified 27,262 patients with CD diagnosed in 2002-2017 and 132,922 age- and sex-matched general population comparators. Diagnoses of IBS were obtained from nationwide inpatient and non-primary outpatient records. Cox regression estimated hazard ratios (aHRs) for IBS adjusted for education level and Charlson Comorbidity Index. To reduce potential surveillance bias our analyses considered incident IBS diagnosis ≥1 year after CD diagnosis. Using conditional logistic regression, secondary analyses were calculated to estimate odds ratios (ORs) for IBS diagnosis ≥1 year before CD diagnosis. RESULTS: During an average of 11.1 years of follow-up, 732 celiac patients (2.7%) were diagnosed with IBS vs 1131 matched general population comparators (0.9%). Overall (≥1-year of follow-up), the aHR for IBS was 3.11 (95% confidence interval [CI], 2.83-3.42), with aHR of 2.00 (95% CI, 1.63-2.45) after ≥10 years of follow-up. Compared with siblings (n = 32,010), celiac patients (n = 19,211) had ≥2-fold risk of later IBS (aHR, 2.42; 95% CI, 2.08-2.82). Compared with celiac patients with mucosal healing, those with persistent villus atrophy on follow-up biopsy were less likely to be diagnosed with IBS (aHR, 0.66; 95% CI, 0.46-0.95). CD was also associated with having an earlier IBS diagnosis (OR, 3.62; 95% CI, 3.03-4.34). CONCLUSIONS: In patients with CD, the risk of IBS is increased long before and after diagnosis. Clinicians should be aware of these long-term associations and their implications on patient management.

Patients' experiences of dietary changes during a structured dietary intervention for irritable bowel syndrome.

BACKGROUND: Diet plays an important role in management of gastrointestinal (GI) symptoms in patients with irritable bowel syndrome (IBS). Restrictive diets have gained popularity as treatment for IBS, but no studies have examined the patients' experiences of implementing such diets. Thus, the present study aimed to explore the experience of patients with IBS undergoing a structured dietary intervention. METHODS: Using inductive content analysis, semi-structured interviews were conducted in 19 patients with IBS, who were recruited from a randomised controlled trial evaluating two different restrictive diets for 4 weeks: a diet low in total carbohydrates; and a diet low in fermentable oligo-, di- and monosaccharides and polyols (i.e., FODMAP) combined with traditional IBS dietary advice. RESULTS: Three main themes developed from the qualitative analysis and together they describe the dietary intervention as supportive, as well as the dietary changes as challenging and contributing to reflection. Patients found the dietary support effective in both initiating and adhering to their dietary changes. Despite the support, the implementation of the diet was perceived as challenging when it interfered with other important aspects of their lives. However, going through the dietary change process, the patients began to reflect on their eating behaviours, which enabled individual dietary adjustments. The adjustments that patients maintained were not only a result of alleviation of GI symptoms, but also based on personal preferences. CONCLUSIONS: Patients with IBS undergoing restrictive diets appear to benefit from structured support. However, considering the individual patient's life situation and personal preferences, individualised dietary options should be encouraged to achieve long-term dietary changes.

Temporal stability of fecal metabolomic profiles in irritable bowel syndrome.

BACKGROUND: The potential of the fecal metabolome to serve as a biomarker for irritable bowel syndrome (IBS) depends on its stability over time. Therefore, this study aimed to determine the temporal dynamics of the fecal metabolome, and the potential relationship with stool consistency, in patients with IBS and healthy subjects. METHODS: Fecal samples were collected in two cohorts comprising patients with IBS and healthy subjects. For Cohort A, fecal samples collected during 5 consecutive days were analyzed by gas chromatography-tandem mass spectrometry (GC-MS/MS). For Cohort B, liquid chromatography-MS (LC-MS) was used to analyze fecal samples collected at week 0 (healthy and IBS) and at week 4 (patients only). Stool consistency was determined by the Bristol Stool Form scale. KEY RESULTS: Fecal samples were collected from Cohort A (seven healthy subjects and eight IBS patients), and Cohort B (seven healthy subjects and 11 IBS patients). The fecal metabolome of IBS patients was stable short-term (Cohort A, 5 days and within the same day) and long-term (Cohort B, 4 weeks). A similar trend was observed over 5 days in the healthy subjects of Cohort A. The metabolome dissimilarity was larger between than within participants over time in both healthy subjects and IBS patients. Further analyses showed that patients had greater range of stool forms (types) than healthy subjects, with no apparent influence on metabolomic dynamics. CONCLUSION & INFERENCES: The fecal metabolome is stable over time within IBS patients as well as healthy subjects. This supports the concept of a stable fecal metabolome in IBS despite fluctuations in stool consistency, and the use of single timepoint sampling to further explore how the fecal metabolome is related to IBS pathogenesis.

Symptom profiles compatible with disorders of gut-brain interaction (DGBI) in organic gastrointestinal diseases: A global population-based study.

BACKGROUND: Patients with organic gastrointestinal (GI) diseases and diabetes mellitus (DM) can have concomitant disorders of gut-brain interaction (DGBI). OBJECTIVE: This study aimed to compare the global prevalence of DGBI-compatible symptom profiles in adults with and without self-reported organic GI diseases or DM. METHODS: Data were collected in a population-based internet survey in 26 countries, the Rome Foundation Global Epidemiology Study (n = 54,127). Individuals were asked if they had been diagnosed by a doctor with gastroesophageal reflux disease, peptic ulcer, coeliac disease, inflammatory bowel disease (IBD), diverticulitis, GI cancer or DM. Individuals not reporting the organic diagnosis of interest were included in the reference group. DGBI-compatible symptom profiles were based on Rome IV diagnostic questions. Odds ratios (ORs [95% confidence interval]) were calculated using mixed logistic regression models. RESULTS: Having one of the investigated organic GI diseases was linked to having any DGBI-compatible symptom profile ranging from OR 1.64 [1.33, 2.02] in GI cancer to OR 3.22 [2.80, 3.69] in IBD. Those associations were stronger than for DM, OR 1.26 [1.18, 1.35]. Strong links between organic GI diseases and DGBI-compatible symptom profiles were seen for corresponding (e.g., IBD and bowel DGBI) and non-corresponding (e.g., IBD and esophageal DGBI) anatomical regions. The strongest link was seen between fecal incontinence and coeliac disease, OR 6.94 [4.95, 9.73]. After adjusting for confounding factors, associations diminished, but persisted. CONCLUSION: DGBI-compatible symptom profiles are more common in individuals with self-reported organic GI diseases and DM compared to the general population. The presence of these concomitant DGBIs should be considered in the management of organic (GI) diseases.

A low FODMAP diet plus traditional dietary advice versus a low-carbohydrate diet versus pharmacological treatment in irritable bowel syndrome (CARIBS): a single-centre, single-blind, randomised controlled trial.

BACKGROUND: Dietary advice and medical treatments are recommended to patients with irritable bowel syndrome (IBS). Studies have not yet compared the efficacy of dietary treatment with pharmacological treatment targeting the predominant IBS symptom. We therefore aimed to compare the effects of two restrictive dietary treatment options versus optimised medical treatment in people with IBS. METHODS: This single-centre, single-blind, randomised controlled trial was conducted in a specialised outpatient clinic at the Sahlgrenska University Hospital, Gothenburg, Sweden. Participants (aged ≥18 years) with moderate-to-severe IBS (Rome IV; IBS Severity Scoring System [IBS-SSS] ≥175) and no other serious diseases or food allergies were randomly assigned (1:1:1) by web-based randomisation to receive a diet low in fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAPs) plus traditional IBS dietary advice recommended by the UK National Institute for Health and Care Excellence (hereafter the LFTD diet), a fibre-optimised diet low in total carbohydrates and high in protein and fat (hereafter the low-carbohydrate diet), or optimised medical treatment based on predominant IBS symptom. Participants were masked to the names of the diets, but the pharmacological treatment was open-label. The intervention lasted 4 weeks, after which time participants in the dietary interventions were unmasked to their diets and encouraged to continue during 6 months' follow-up, participants in the LFTD group were instructed on how to reintroduce FODMAPs, and participants receiving pharmacological treatment were offered diet counselling and to continue with their medication. The primary endpoint was the proportion of participants who responded to the 4-week intervention, defined as a reduction of 50 or more in IBS-SSS relative to baseline, and was analysed per modified intention-to-treat (ie, all participants who started the intervention). Safety was analysed in the modified intention-to-treat population. This trial is registered with ClinicalTrials.gov, NCT02970591, and is complete. FINDINGS: Between Jan 24, 2017, and Sept 2, 2021, 1104 participants were assessed for eligibility and 304 were randomly assigned. Ten participants did not receive their intervention after randomisation and thus 294 participants were included in the modified intention-to-treat population (96 assigned to the LFTD diet, 97 to the low-carbohydrate diet, and 101 to optimised medical treatment). 241 (82%) of 294 participants were women and 53 (18%) were men and the mean age was 38 (SD 13). After 4 weeks, 73 (76%) of 96 participants in the LFTD diet group, 69 (71%) of 97 participants in the low-carbohydrate diet group, and 59 (58%) of 101 participants in the optimised medical treatment group had a reduction of 50 or more in IBS-SSS compared with baseline, with a significant difference between the groups (p=0·023). 91 (95%) of 96 participants completed 4 weeks in the LFTD group, 92 (95%) of 97 completed 4 weeks in the low-carbohydrate group, and 91 (90%) of 101 completed 4 weeks in the optimised medical treatment group. Two individuals in each of the intervention groups stated that adverse events were the reason for discontinuing the 4-week intervention. Five (5%) of 91 participants in the optimised medical treatment group stopped treatment prematurely due to side-effects. No serious adverse events or treatment-related deaths occurred. INTERPRETATION: Two 4-week dietary interventions and optimised medical treatment reduced the severity of IBS symptoms, with a larger effect size in the diet groups. Dietary interventions might be considered as an initial treatment for patients with IBS. Research is needed to enable personalised treatment strategies. FUNDING: The Healthcare Board Region Västra Götaland, the Swedish Research Council, the Swedish Research Council for Health, Working Life and Welfare, AFA Insurance, grants from the Swedish state, the Wilhelm and Martina Lundgren Science Foundation, Skandia, the Dietary Science Foundation, and the Nanna Swartz Foundation.

Review article: A practical approach to persistent gastrointestinal symptoms in inflammatory bowel disease in remission.

BACKGROUND: Persistent gastrointestinal symptoms are prevalent in adult patients with inflammatory bowel disease (IBD), even when endoscopic remission is reached. These symptoms can have profound negative effects on the quality of life of affected patients and can be difficult to treat. They may be caused by IBD-related complications or comorbid disorders, but they can also be explained by irritable bowel syndrome (IBS)-like symptoms. AIMS: To provide a practical step-by-step guide to diagnose and treat persistent gastrointestinal symptoms in patients with IBD in remission via a personalised approach. METHODS: We scrutinised relevant literature on causes, diagnostics and treatment of persistent gastrointestinal symptoms (abdominal pain or discomfort, bloating, abdominal distension, diarrhoea, constipation and faecal incontinence) in patients with IBD in remission. RESULTS: A graphical practical guide for several steps in diagnosing, identifying potential triggers and adequate treatment of persistent gastrointestinal symptoms in IBD in remission is provided based on supporting literature. The first part of this review focuses on the diagnostic and treatment approaches for potential IBD-related complications and comorbidities. The second part describes the approach to IBS-like symptoms in IBD in remission. CONCLUSIONS: Persistent gastrointestinal symptoms in IBD in remission can be traced back to potential pathophysiological mechanisms in individual patients and can be treated adequately. For both IBD-related complications and comorbidities and IBS-like symptoms in IBD in remission, pharmacological, dietary, lifestyle or psychological treatments can be effective. A systematic and personalised approach is required to reduce the burden for patients, healthcare systems, and society.