Rome III vs Rome IV criteria for irritable bowel syndrome: A comparison of clinical characteristics in a large cohort study.

BACKGROUND: The Rome criteria for irritable bowel syndrome (IBS) have been revised and are expected to apply only to the subset of Rome III IBS subjects with abdominal pain as predominant symptom, occurring at least once a week. The aim of this study was to determine the percentage of Rome III IBS subjects that fulfills Rome IV criteria and to evaluate differences between Rome IV-positive and Rome IV-negative subjects. METHODS: Four hundred and four Rome III IBS subjects completed a 14-day end-of-day symptom diary, the Gastrointestinal Symptom Rating Scale (GSRS), Hospital Anxiety and Depression Scale, and RAND 36-item Short-Form Health Survey (SF-36). Diary-based surrogate Rome IV criteria were defined as occurrence of abdominal pain at least 1 day each week with a severity of ≥2 (mild; definition 1) or ≥3 (considerable; definition 2). KEY RESULTS: Using surrogate Rome IV criteria, 353 (87.4%, definition 1) and 249 (61.6%, definition 2) subjects were defined as Rome IV positive. These patients were more often female, younger, and recruited from secondary/tertiary care compared with Rome IV-negative subjects. They also presented with higher abdominal pain scores and gastrointestinal (GI) symptom severity on both end-of-day diary and GSRS, higher psychological symptom scores, and lower quality of life compared with Rome IV-negative subjects. CONCLUSIONS AND INFERENCES: The Rome IV IBS population likely reflects a subgroup of Rome III IBS patients with more severe GI symptomatology, psychological comorbidities, and lower quality of life. This implies that results from Rome III IBS studies may not be directly comparable to those from Rome IV IBS populations.

Habitual diet and diet quality in Irritable Bowel Syndrome: A case-control study.

BACKGROUND: Diet is considered to be a key factor in symptom generation in Irritable Bowel Syndrome (IBS) and patients tend to exclude food products from their diet in pursue of symptom relief, which may impair diet quality. METHODS: We evaluated habitual dietary intake in IBS patients with regard to nutrients and food products using an extensive food frequency questionnaire. One hundred ninety-four IBS patients were compared to 186 healthy controls using multiple logistic regression analysis. An overall diet quality score was calculated for each participant based on the criteria of the Dutch Healthy Diet (DHD) index. KEY RESULTS: A lower DHD-score was found for IBS (mean [SD]: 52.9 [9.6]) vs controls (55.1 [9.2], P=.02). The diet of patients was lower in fibers (21 g vs 25 g per day, P=.002) and fructose (14 g vs 16 g, P=.033), while higher in total fat (37% vs 36% of total energy intake, P=.010) and added sugars (46 g vs 44 g, P=.029). Differences in daily intake of food products included lower consumption of apples (40 g vs 69 g, P<.001), pasta (28 vs 37 g, P=.029) and alcoholic beverages (130 g vs 193 g, P=.024) and higher consumption of processed meat (38 g vs 29 g, P<.001). Some of these findings correlated with gastrointestinal symptoms, showing differences between IBS subtypes. CONCLUSIONS AND INFERENCES: Differences in habitual diet were described, showing lower diet quality in IBS patients compared to controls, with increased consumption of fat and lower intake of fibers and fructose. Our data support the importance of personalized and professional nutritional guidance of IBS patients.

Biomarkers for visceral hypersensitivity in patients with irritable bowel syndrome.

BACKGROUND: Increased visceral sensitivity is observed in up to 60% of patients with Irritable Bowel Syndrome (IBS). Mucosal inflammation, altered neuroendocrine activity and intraluminal metabolic processes may contribute to the development of visceral hypersensitivity. Previously, we demonstrated that biomarkers, indicative for these biological processes, were altered in IBS patients compared to healthy controls. However, how these processes relate to visceral hypersensitivity is unknown. AIM: The aim of this study was to provide insight in biological processes associated with visceral hypersensitivity. Fecal and plasma biomarkers were measured in normosensitive and hypersensitive IBS patients. METHODS: A total of 167 IBS patients underwent a rectal barostat procedure to assess visceral sensitivity to pain. Based on the outcome, patients were classified into a normosensitive or hypersensitive group. Calprotectin, human ß-defensin 2 (HBD2), chromogranin A (CgA), and short chain fatty acids (SCFAs) were measured in feces, citrulline in plasma, and serotonin and its main metabolite 5-hydroxyindoleacetic acid (5-HIAA) in platelet-poor plasma. KEY RESULTS: Fecal markers and plasma citrulline were measured in 83 hypersensitive and 84 normosensitive patients, while platelet-poor plasma for the assessment of serotonin and 5-HIAA was available for a subgroup, i.e. 53 hypersensitive and 42 normosensitive patients. No statistically significant differences were found in concentrations of biomarkers between groups. Adjustment of the analyses for potential confounders, such as medication use, did not alter this conclusion. CONCLUSIONS & INFERENCES: Our findings do not support a role for the biological processes as ascertained by biomarkers in visceral hypersensitivity in IBS patients. This study is registered in the US National Library of Medicine (clinicaltrials.gov, NCT00775060).

Alterations in serotonin metabolism in the irritable bowel syndrome.

BACKGROUND: Alterations in serotonin (5-HT) metabolism have been postulated to play a role in the pathogenesis of irritable bowel syndrome (IBS). However, previous reports regarding 5-HT metabolism in IBS are contradicting. AIM: To compare platelet poor plasma (PPP) 5-HT and 5-hydroxyindole acetic acid (5-HIAA) levels and their ratio in a large cohort of IBS patients and healthy controls (HC), including IBS-subgroup analysis. METHODS: Irritable bowel syndrome patients and HC were evaluated for fasting PPP 5-HT and 5-HIAA levels. Furthermore, GI-symptom diary, GSRS, quality of life, anxiety and depression scores were assessed in the 2 weeks before blood sampling. RESULTS: One hundred and fifty four IBS patients and 137 HC were included. No differences were detected in plasma 5-HT between groups. The 5-HIAA concentrations and 5-HIAA/5-HT ratio were significantly lower in IBS compared to HC: 24.6 ± 21.9 vs. 39.0 ± 29.5 µg/L (P < 0.001) and 8.4 ± 12.2 vs. 13.5 ± 16.6 (P < 0.01), respectively. Subtype analysis for 5-HIAA showed all IBS subtypes to be significantly different from HC. The 5-HIAA/5-HT ratio was significantly lower in the IBS-M subtype vs. HC. Linear regression analysis points to an influence of gender but not of GI-symptoms, psychological scores or medication use. CONCLUSIONS: We demonstrated that fasting 5-HT plasma levels are not significantly different in IBS patients compared to controls. However, decreased 5-HIAA levels and 5-HIAA/5-HT ratio in IBS patients may reflect altered serotonin metabolism in IBS. Gender affects 5-HIAA levels in IBS patients, but no effects of drugs, such as SSRIs, or higher GI-symptom or psychological scores were found.

The Experience Sampling Method--a new digital tool for momentary symptom assessment in IBS: an exploratory study.

BACKGROUND: Retrospective questionnaires are frequently used for symptom assessment in irritable bowel syndrome (IBS) patients, but are influenced by recall bias and circumstantial and psychological factors. These limitations may be overcome by random, repeated, momentary assessment during the day, using electronic Experience Sampling Methodology (ESM). Therefore, we compared symptom assessment by ESM to retrospective paper questionnaires in IBS patients. METHODS: Twenty-six IBS patients (Rome III) were included, of which 16 were diagnosed with panic disorder (DSM-IV-TR). Patients scored symptoms using end-of-day diaries during 14 days and the gastrointestinal symptom rating scale (GSRS) once. ESM was used on seven consecutive days during the same time period. KEY RESULTS: End-of-day diary abdominal pain scores were 0.4 (SE 0.1, p < 0.001) point higher (on a 1-to-5-point scale) compared to corresponding ESM mean-scores in IBS patients. The difference was even more pronounced for upper abdominal pain scores assessed by the GSRS (4.77 ± 1.50) compared to ESM mean-scores (2.44 ± 1.30, p < 0.001), both on 1-to-7-point scale. For flatulence, comparable results were found. Nausea and belching scores showed small, but significant differences between end-of-day diary and ESM. All tested symptoms were scored higher on GSRS compared to ESM mean-scores (p < 0.01). Affective comorbidity did not influence differences in pain reporting between methods. CONCLUSIONS & INFERENCES: IBS patients report higher scores for abdominal pain in retrospective questionnaires compared to ESM, with a tendency to report peak rather than average pain scores. ESM can provide more insight in symptom course and potential triggers, and may lead to a better understanding of IBS symptomatology.

Small intestinal permeability is increased in diarrhoea predominant IBS, while alterations in gastroduodenal permeability in all IBS subtypes are largely attributable to confounders.

BACKGROUND: Intestinal permeability has been studied in small groups of IBS patients with contrasting findings. AIMS: To assess intestinal permeability at different sites of the GI tract in different subtypes of well-characterised IBS patients and healthy controls (HC), and to assess potential confounding factors. METHODS: IBS patients and HC underwent a multi-sugar test to assess site-specific intestinal permeability. Sucrose excretion and lactulose/rhamnose ratio in 0-5 h urine indicated gastroduodenal and small intestinal permeability, respectively. Sucralose/erythritol ratio in 0-24 h and 5-24 h urine indicated whole gut and colonic permeability, respectively. Linear regression analysis was used to assess the association between IBS groups and intestinal permeability and to adjust for age, sex, BMI, anxiety or depression, smoking, alcohol intake and use of medication. RESULTS: Ninety-one IBS patients, i.e. 37% IBS-D, 23% IBS-C, 33% IBS-M and 7% IBS-U and 94 HC were enrolled. Urinary sucrose excretion was significantly increased in the total IBS group [µmol, median (Q1;Q3): 5.26 (1.82;11.03) vs. 2.44 (0.91;5.85), P < 0.05], as well as in IBS-C and IBS-D vs. HC. However, differences attenuated when adjusting for confounders. The lactulose/rhamnose ratio was increased in IBS-D vs. HC [0.023 (0.013;0.038) vs. 0.014 (0.008;0.025), P < 0.05], which remained significant after adjustment for confounders. No difference was found in 0-24 and 5-24 h sucralose/erythritol ratio between groups. CONCLUSIONS: Small intestinal permeability is increased in patients with IBS-D compared to healthy controls, irrespective of confounding factors. Adjustment for confounders is necessary when studying intestinal permeability, especially in a heterogeneous disorder such as IBS.