Iris Posserud

Small intestinal bacterial overgrowth in patients with irritable bowel syndrome

Background: Small intestinal bacterial overgrowth (SIBO) has been proposed to be common in irritable bowel syndrome (IBS), with altered small-bowel motility as a possible predisposing factor. Aim: To assess the prevalence of SIBO, by culture of small-bowel aspirate, and its correlation to symptoms and motility in IBS. Methods: 162 patients with IBS who underwent small-bowel manometry and culture of jejunal aspirate were included. Cultures from 26 healthy subjects served as controls. Two definitions of altered flora were used: the standard definition of SIBO (⩾105 colonic bacteria/ml), and mildly increased counts of small-bowel bacteria (⩾95th centile in controls). Results: SIBO (as per standard definition) was found in 4% of both patients and controls. Signs of enteric dysmotility were seen in 86% of patients with SIBO and in 39% of patients without SIBO (p = 0.02). Patients with SIBO had fewer phase III activities (activity fronts) than patients without SIBO (p = 0.08), but otherwise no differences in motility parameters were seen. Mildly increased bacterial counts (⩾5×103/ml) were more common in patients with IBS than in controls (43% vs 12%; p = 0.002), but this was unrelated to small intestinal motility. No correlation between bacterial alterations and symptom pattern was observed. Conclusions: The data do not support an important role for SIBO according to commonly used clinical definitions, in IBS. However, mildly increased counts of small-bowel bacteria seem to be more common in IBS, and needs further investigation. Motility alterations could not reliably predict altered small-bowel bacterial flora.

Altered visceral perceptual and neuroendocrine response in patients with irritable bowel syndrome during mental stress

Background and aims: Stress often worsens the symptoms of irritable bowel syndrome (IBS). We hypothesised that this might be explained by altered neuroendocrine and visceral sensory responses to stress in IBS patients. Subjects and methods: Eighteen IBS patients and 22 control subjects were assessed using rectal balloon distensions before, during, and after mental stress. Ten controls and nine patients were studied in supplementary sessions. Rectal sensitivity (thresholds and intensity—visual analogue scale (VAS)) and perceived stress and arousal (VAS) were determined. Plasma levels of corticotropin releasing factor (CRF), adrenocorticotropic hormone (ACTH), cortisol, noradrenaline, and adrenaline were analysed at baseline, immediately after stress, and after the last distension. Heart rate was recorded continuously. Results: Thresholds were increased during stress in control subjects (p<0.01) but not in IBS patients. Both groups showed lower thresholds after stress (p<0.05). Repeated distensions without stress did not affect thresholds. Both groups showed increased heart rate (p<0.001) and VAS ratings for stress and arousal (p<0.05) during stress. Patients demonstrated higher ratings for stress but lower for arousal than controls. Basal CRF levels were lower in patients (p<0.05) and increased significantly during stress in patients (p<0.01) but not in controls. Patients also responded with higher levels of ACTH during stress (p<0.05) and had higher basal levels of noradrenaline than controls (p<0.01). Controls, but not patients, showed increased levels of adrenaline and noradrenaline in response to stress (p<0.05). Conclusions: Stress induced exaggeration of the neuroendocrine response and visceral perceptual alterations during and after stress may explain some of the stress related gastrointestinal symptoms in IBS.

Clinical trial: the effects of a fermented milk containing three probiotic bacteria in patients with irritable bowel syndrome – a randomized, double‐blind, controlled study

Background  The effects of probiotic bacteria in IBS remain controversial.

Health-Related Quality of Life in Patients Attending a Gastroenterology Outpatient Clinic: Functional Disorders Versus Organic Diseases

BACKGROUND & AIMS Several gastrointestinal (GI) disorders have major effects on health-related quality of life (HRQOL), but there are few direct comparisons between functional GI disorders and organic GI diseases. This study aimed to compare HRQOL between these 2 groups and to assess factors of importance for HRQOL. METHODS Three hundred ninety-nine consecutive patients attending a GI outpatient clinic completed HRQOL instruments (Short Form 36 [SF-36] and Psychological General Well-Being index [PGWB]) and the Gastrointestinal Symptom Rating Scale (GSRS). For the analyses we divided the patients into 2 diagnostic groups: functional GI disorders (n = 112) and organic GI diseases (n = 287). RESULTS Compared with norm values on SF-36 and PGWB, both patient groups exhibited profound reductions in HRQOL. After correcting for age, gender, and disease duration, patients with a functional GI disorder had significantly lower scores than patients with an organic GI disease on 6 of 8 SF-36 domains and 5 of 6 PGWB domains. Vitality and anxiety on PGWB, abdominal pain and diarrhea on GSRS, age, and gender independently contributed to the physical component score of SF-36 (adjusted R(2) = 32%). Patients with a functional GI disorder had more severe reflux, abdominal pain, constipation, and indigestion, but the severity of diarrhea did not differ between the groups. HRQOL was reduced with increasing severity of GI symptoms. CONCLUSION GI disorders have profound effects on HRQOL, and the impact is greater in patients with functional GI disorders as compared with organic GI diseases. The reduction in HRQOL is associated with the severity of both psychological and GI symptoms.

Subtyping the irritable bowel syndrome by predominant bowel habit: Rome II versus Rome III

The agreement between subtyping irritable bowel syndrome (IBS) patients based on Rome II criteria versus Rome III criteria is unknown.

Structured patient education is superior to written information in the management of patients with irritable bowel syndrome: a randomized controlled study.

Objective Education and reassurance are proposed to be of great importance in the management of patients with irritable bowel syndrome (IBS), but few trials supporting this are available. Our aim was to compare the effects of a structured patient group education (IBS school) versus receiving written information in the form of an IBS guidebook, on knowledge, symptoms, and quality of life in IBS patients. Methods Patients with IBS according to the Rome II criteria were randomized to participate in the group education or to receive the guidebook. The effects were evaluated by self-administered questionnaires at 3 and 6 months after baseline. Results One hundred and forty-three patients – 71 in the guidebook group and 72 in the IBS school group – completed the study. Compared with the guidebook group, the patients in the education group showed greater reduction in IBS symptom severity and gastrointestinal (GI)-specific anxiety, as well as greater improvement in perceived knowledge of IBS. Several aspects of health-related quality of life were significantly improved after the group education, but not in the group who received the written information. Conclusion A structured patient group education is superior to written information to enhance knowledge of IBS, and improve GI symptoms and GI-specific anxiety in IBS patients.

Hypervigilance in irritable bowel syndrome compared with organic gastrointestinal disease

OBJECTIVE Irritable bowel syndrome (IBS) patients are suggested to selectively attend to gastrointestinal (GI) sensations compared with healthy controls. However, it remains unclear whether there are differences between IBS and other chronic GI disorders. We aimed to evaluate the presence of hypervigilance towards the GI tract in IBS compared with patients with organic GI diseases. METHODS We included 36 IBS patients and 40 age- and gender-matched patients with organic GI disease. They completed the Hospital Anxiety and Depression Scale (HADS) and underwent three tests: (1) word association-write down as many words as possible representing signs of disease; (2) word recognition (tachistoscope)-four categories of words (positive affects, non-GI symptoms, GI symptoms, negative affects) displayed for increasing time until identified; (3) word recollection-memorize words (10 GI symptoms, 10 positive affects, 10 negative affects). RESULTS The word-association task did not show group differences. IBS patients were significantly faster than organic GI patients at recognizing words representing GI symptoms (21 vs. 26 ms; P=.04) and negative affects (27 vs. 34 ms; P=.03), but also tended to be faster at recognizing positive affects (24 vs. 29 ms; P=.08) and non-GI symptoms (22 vs. 27 ms; P=.2). Both groups remembered a similar number of words, but IBS patients tended to recall more incorrect GI words than organic patients (1.3 vs. 1.0; P=.06). There were no group differences in HADS scores. CONCLUSION Compared to patients with organic GI disease, IBS patients seem to be hypervigilant for information regarding GI sensations and maybe also negative information.

Predictors of subjective fatigue in chronic gastrointestinal disease

Background  Fatigue is a common, but poorly understood symptom in patients with chronic gastrointestinal (GI) diseases.

Randomised clinical trial: symptoms of the irritable bowel syndrome are improved by a psycho-education group intervention

Evidence supports the effectiveness of cognitive behavioural approaches in improving the symptoms of the irritable bowel syndrome (IBS). Duration, cost and resistance of many patients towards a psychological therapy have limited their acceptance.

Increased TLR2 expression on blood monocytes in irritable bowel syndrome patients.

Objectives The understanding of the mechanisms for increased immune activation in subgroups of patients with irritable bowel syndrome (IBS) is incomplete. We hypothesized that monocytes are more activated in patients with IBS than in the healthy population. We therefore examined activation phenotype and cytokine secretion of blood monocytes. Methods Blood samples from 74 patients with IBS and 30 controls were obtained. The activation phenotype of CD11c+CD14+ monocytes and cytokine secretion in serum and in peripheral blood mononuclear cells cultured with or without lipopolysaccharide was determined. Gastrointestinal and psychological symptom severity and quality of life were assessed using validated questionnaires. Results Monocytes from patients demonstrated an increased expression of toll-like receptor (TLR) 2, whereas the expression on monocytes of TLR4, HLA-DR, CD40, CD80 and CD86 was comparable in patients and controls. The expression of activation markers on monocytes did not correlate with gastrointestinal or extracolonic symptom severity, but the expressions of TLR2, HLA-DR and CD86 were associated with less severe psychological symptoms and better social and physical well-being. Cytokine secretion in serum and peripheral blood mononuclear cell cultures was comparable in patients and controls. A subgroup of patients (15%) who had TLR2 and HLA-DR expression intensity above the level seen in controls reported less severe psychosocial symptoms. Conclusion Patients with IBS have increased expression of TLR2 on monocytes and the activation level on monocytes correlates with less severe psychological symptoms and better quality of life. Thus, our data implicate less importance of psychosocial factors and increased importance of immunological parameters for symptom generation in a subgroup of patients with IBS.