system
Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Adult, Autonomic Nervous System, Autonomic Pathways, Case-Control Studies, Colonic Diseases, Functional, Constipation, Diarrhea, Electrocardiography, Female, Heart Rate, Humans, Hydrocortisone, Postprandial Period, Saliva.
user
Do diarrhea- and constipation-predominant IBS patients differ in postprandial autonomic and cortisol responses? Context: As the primary link between brain and gut, autonomic and endocrine dysfunction may play a role in the pathophysiology of the irritable bowel syndrome (IBS). The aim of this study was to assess autonomic, endocrine, and symptomatic responses to food intake in diarrhea-predominant and constipation-predominant IBS patients, compared to normals. Twelve women with diarrhea-predominant or alternating IBS (IBS-D), 12 women with constipation predominant IBS (IBS-C), and 20 healthy women participated. GI symptoms, saliva cortisol concentration, heart rate, and heart rate variability were assessed at baseline and after a meal. Spectral analysis of heart rate variability was used as a measure of the sympathovagal regulation of the heart rate. Both groups of IBS patients showed a significant postprandial increase in GI symptoms. IBS-D showed a significant increase in the low frequency/high frequency band ratio and a decrease in the high frequency band power during the first postmeal period, which was significantly different, not only from controls, but also from IBS-C. IBS-D also showed a significant postprandial increase in cortisol, which was not evident in controls or IBS-C. There was a significant correlation between the vagal response and the postprandial increase in GI symptoms in IBS-D (r = 0.6, p < 0.05).
assistant
These findings support the notion that the IBS symptom groups are characterized by different physiological responses to visceral stimuli, and point to a role of autonomic pathways in IBS symptomatology. Final Decision: yes