Placebo analgesia is a psychosocial context effect that is rarely studied in visceral pain. Patients with irritable bowel syndrome (IBS) exhibit visceral hyperalgesia and heightened affective/cognitive brain region activation during visceral stimuli. Psychological factors alter the pain and brain activation pattern, and these changes are more pronounced in IBS patients. Expectation constitutes the major neuropsychological mechanism in the placebo effect. This study confirmed the heightened affective/cognitive brain responses in IBS patients during visceral placebo analgesia using a placebo model with expectation, which was enhanced by suggestion and conditioning. Seventeen IBS patients and 17 age-/sex-matched controls were enrolled. Psychophysical inventories (Hospital Anxiety and Depression Scale [HADS], visual analogue scale, and short-form McGill questionnaire) were completed. Brain activity during placebo intervention and anticipation was assessed in response to rectal distension using 3T-functional magnetic resonance imaging. Suggestion-/conditioning-enhanced placebo was used to convince controls/patients of the efficacy of a newly developed intravenous drug (saline, in actuality) for the relief of rectal distension-induced visceral pain. A comparable visceral placebo analgesia was observed in IBS patients and control subjects. IBS patients demonstrated a higher HADS-anxiety score, which was predictive of a weak placebo effect. Suggestion-/conditioning-enhanced placebo evoked more activity in affective/cognitive brain regions (insula, midcingulate cortex, and ventrolateral prefrontal cortex [VLPFC]) in IBS patients than in healthy controls. VLPFC was also more active during anticipation in IBS patients. In conclusion, IBS patients and control subjects achieved comparable placebo analgesia during experimentally induced rectal pain. The visceral placebo analgesia produced heightened activity in affective/cognitive brain regions in IBS patients.

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Distal RSG patients may have decreased SW frequency and less meal ingestion changed EGG parameters in terms of SW frequency, normality and stability, whereas their EGG power remained unchanged irrespective of meal ingestion.

Background/AimsBoth sexual and physical abuse history have been reported to be associated with irritable bowel syndrome (IBS) in Western countries. The impact of abuse history in IBS patients in Asia remains unclear. We aim to determine the prevalence of abuse history, its associated psychological profiles, and sleep problems among IBS patients in Taiwan. MethodsIn total, 194 Rome III-defined IBS patients were invited to participate. Age-and sex-matched healthy carriers of chronic hepatitis B or hepatitis C without chronic abdominal symptoms were identified as disease-controls. We administered a validated questionnaire to evaluate bowel symptoms, physical/sexual abuse history, anxiety/depression (Hospital Anxiety and Depression Scale [HADS]), and sleep quality. ResultsIBS patients had a significantly higher prevalence of sexual abuse history than the disease-control group both before (16.5% vs 6.7%, P < 0.05) and after (16.0% vs 6.6%, P < 0.05) adolescence. These significant differences were mainly observed in women (13.4% vs 3.4%, P < 0.05). No difference was noted in history of physical abuse between the 2 groups. IBS patients with a history of sexual abuse had significantly higher HADS scores and higher frequencies of sleep difficulty than those without. ConclusionsIn Taiwan, sexual abuse history was more prevalent in female IBS patients than controls. Sexual abuse history may contribute to higher anxiety/depression levels and sleep difficulties, which are commonly experienced in IBS patients. In Asia, abuse history should be obtained when approaching IBS patients to facilitate better management.

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