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- Le Neve, B., et al.
(författare)
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A Combined Nutrient and Lactulose Challenge Test Allows Symptom-Based Clustering of Patients With Irritable Bowel Syndrome
- 2013
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Ingår i: American Journal of Gastroenterology. - : Ovid Technologies (Wolters Kluwer Health). - 0002-9270. ; 108:5, s. 786-795
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVES: The aim of the present pilot study was to evaluate the usefulness of a test meal containing lactulose in the non-invasive assessment of visceral sensitivity in irritable bowel syndrome (IBS), and to identify subsets of IBS patients based on gastrointestinal (GI) symptom generation. METHODS: We included 43 patients with IBS (Rome III) and 29 healthy controls. The fasted subjects were served three test meals consisting of a 400-ml liquid breakfast alone or containing lactulose (15 or 25g) in a double-blind crossover design. Seven GI symptoms, overall digestive comfort, and exhaled H2/CH4 were assessed at baseline and every 15min during 4h after meal intake. Anxiety and depression were assessed only at baseline. A mapping of the seven GI symptoms was done using a Principal Component Analysis (4h mean area under the curve, AUC). Independently, a hierarchical cluster analysis was performed on the same parameters to identify GI symptom-based IBS clusters. RESULTS: All three tests were well tolerated. The 25g lactulose challenge enabled discrimination of IBS from healthy controls according to the symptom response. This challenge also enabled clustering of IBS subjects in two subgroups based mainly on bloating, distension, and discomfort symptoms (2,457 (2,043–2,872), 2,450 (1,910–2,990), 2,602 (2,126–3,079) vs. 537 (383–691), 619 (458–780), 643 (432–854); 4h mean AUC; P<0.0001), overall digestive comfort (1807 (1318–2295) vs. 3350 (2942–3758); 4h mean AUC; P<0.0001), and anxiety at baseline (9.2 (7.0–11.5) vs. 5.5 (4.2–6.9); Hospital Anxiety and Depression scale anxiety mean scores; P=0.003). This clustering was independent of the Rome III subtype and the amount of exhaled H2/CH4. CONCLUSIONS: The lactulose challenge test seems to be a promising tool to assess visceral sensitivity in IBS, and to subgroup IBS patients based on their symptom pattern.
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- Lowén, Mats B. O., et al.
(författare)
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Deficient habituation to repeated rectal distensions in irritable bowel syndrome patients with visceral hypersensitivity
- 2015
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Ingår i: Neurogastroenterology and Motility. - : Wiley. - 1350-1925 .- 1365-2982. ; 27:5, s. 646-655
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Tidskriftsartikel (refereegranskat)abstract
- Background Irritable bowel syndrome (IBS) patients show evidence of altered central processing of visceral signals. One of the proposed alterations in sensory processing is an altered engagement of endogenous pain modulation mechanisms. The aim was to test the hypothesis that IBS patients with (IBS-S) and without visceral hypersensitivity (IBS-N) differ in their ability to engage endogenous pain modulation mechanism during habituation to repeated visceral stimuli.Methods Brain blood oxygen level dependent (BOLD) response was measured during repeated rectal distension and its anticipation in 33 IBS patients with and without visceral hypersensitivity and 18 healthy controls (HCs). BOLD response to early and late phase of the distension series was compared within and between groups.Key Results While BOLD response was similar during the early phase of the experiment, IBS-S showed greater BOLD response than IBS-N and HCs during the late phase of the distension series. IBS-S showed increasing BOLD response both to the anticipation and delivery of low intensity rectal distensions in brain regions including insula, anterior and mid cingulate cortex. IBS-N showed decreasing BOLD response to repeated rectal distensions in brain regions including insula, prefrontal cortex and amygdala.Conclusions & Inferences These findings are consistent with compromised ability of IBS-S to respond to repeated delivery of rectal stimuli, both in terms of sensitization of sensory pathways and habituation of emotional arousal. The fact that both IBS subgroups met Rome criteria, and did not differ in terms of reported symptom severity demonstrates that similar symptom patterns can result from different underlying neurobiological mechanisms.
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- Larsson, M., et al.
(författare)
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Brain Response to Expectation and Delivery of Rectal Distensions Before and After Hypnotherapy and Education Intervention in Irritable Bowel Syndrome (IBS) : an fMRI Study
- 2011
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Konferensbidrag (refereegranskat)abstract
- Aim & MethodsWe aimed to determine the effect of standardized hypnosis treatment (HYP) on symptom outcomes and brain activity compared to an education intervention (EDU). Twenty-seven women with IBS were evaluated before and after treatment with hypnotherapy (n=17) or educational intervention (n=10). Behavioural treatment outcomes were determined by Severity Scoring System (IBS-SSS). A decrease of 50 points in SSS score was considered clinically significant treatment response. Blood oxygenated level dependent (BOLD) signal were acquired by using a 1.5 T magnetic resonance scanner during expectation and delivery of large rectal distension (45 mmHg). Group comparisons of treatment effects were performed within the general linear model in SPM8. Region of interest analyses were performed with significance threshold of p<0.05, family-wise error corrected.ResultsThere were no group differences in baseline SSS scores. Clinically significant change in SSS was observed in HYP (82%, n=14) and EDU (60%, n=6). Mean improvement in SSS was 108 (range -277 to 29) in HYP and 62 (range -250 to 79) in EDU (ns). During cued expectation of rectal distension, HYP was associated with significantly decreased activation in the left dorsal and ventral anterior insula, left mid insula, left ventrolateral prefrontal cortex (vlPFC) and left dorsolateral prefrontal cortex (dlPFC). Respectively, the EDU group showed less BOLD activity in the left ventral anterior insula after treatment. No significant treatment effect on brain response to the 45 mmHg distension was observed.ConclusionWhile both treatments improve IBS symptoms, the standardized hypnosis treatment has a more widespread central effect compared to education. The brain effects are seen during the expectation of rectal discomfort, but not during the experience of aversive rectal distensions. These findings are consistent with a HYP-induced reduction in pain expectation, rather than pain perception
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| 6. |
- Lowén, Mats, et al.
(författare)
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Effect of hypnotherapy and educational intervention on brain response to visceral stimulus in the irritable bowel syndrome
- 2013
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Ingår i: Alimentary Pharmacology and Therapeutics. - : Wiley-Blackwell. - 0269-2813 .- 1365-2036. ; 37:12, s. 1184-1197
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Tidskriftsartikel (refereegranskat)abstract
- Background Gut-directed hypnotherapy can reduce IBS symptoms, but the mechanisms underlying this therapeutic effect remain unknown. Aim To determine the effect of hypnotherapy and educational intervention on brain responses to cued rectal distensions in IBS patients. Methods Forty-four women with moderate-to-severe IBS and 20 healthy controls (HCs) were included. Blood oxygen level dependent (BOLD) signals were measured by functional Magnetic Resonance Imaging (fMRI) during expectation and delivery of high- (45mmHg) and low-intensity (15mmHg) rectal distensions. Twenty-five patients were assigned to hypnotherapy (HYP) and 16 to educational intervention (EDU). Thirty-one patients completed treatments and posttreatment fMRI. Results Similar symptom reduction was achieved in both groups. Clinically successful treatment (all responders) was associated with significant BOLD attenuation during high-intensity distension in the dorsal and ventral anterior insula (cluster size 142, P=0.006, and cluster size 101, P=0.005 respectively). Moreover HYP responders demonstrated a prepost treatment BOLD attenuation in posterior insula (cluster sizes 59, P=0.05) while EDU responders had a BOLD attenuation in prefrontal cortex (cluster size 60, P=0.05). Prepost differences for expectation conditions were almost exclusively seen in the HYP group. Following treatment, the brain response to distension was similar to that observed in HCs, suggesting that the treatment had a normalising effect on the central processing abnormality of visceral signals in IBS. Conclusions The abnormal processing and enhanced perception of visceral stimuli in IBS can be normalised by psychological interventions. Symptom improvement in the treatment groups may be mediated by different brain mechanisms. Clinical trial number: NCT01815164.
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