Hassouna, Rim

INTRODUCTION: Bloating, distention, and gas-related gastrointestinal (GI) symptoms are frequently reported by patients across the spectrum of disorders of gut-brain interaction (DGBI). We aimed to characterize these using latent class modeling in a large multinational survey. METHODS: A nationwide survey of adults in the United States, United Kingdom, and Mexico used quota sampling for demographic balance. It included Rome IV diagnostic questions, Intestinal Gas Questionnaire, Patient Health Questionnaires for anxiety and depression (PHQ-4) and somatization (PHQ-12), quality of life (PROMIS Global-10), and lifestyle questions. Latent class analysis was performed using “depmix” in RStudio 4.2.3. RESULTS: A total of 3,471 subjects experiencing bloating and/or distention (mean age 43 years, 57% female) were included. Using 42 demographic and pertinent clinical variables, latent class analysis revealed 6 distinct clusters. The first 2 clusters demonstrated limited-to-moderate impairment in health-related quality of life (HRQoL), with both characterized by some degree of dietary and supplement associations; however, cluster 2 lacked specific triggers observed in other clusters. The subsequent 2 clusters showed favorable HRQoL and mild gas-related symptoms, with only cluster 4 exhibiting distinct dietary triggers. The final 2 clusters, associated with bowel dysfunction, showed a higher prevalence of irritable bowel syndrome (IBS) with constipation and IBS mixed in cluster 5, and IBS with diarrhea in cluster 6. These bowel dysfunction clusters exhibited severe gas symptoms in the preceding 24 hours and greater HRQoL impairment compared with the other 4 clusters. Notably, cluster 5 was linked to dietary triggers, whereas cluster 6 was defined by psychosocial comorbidities. DISCUSSION: Bloating and distention patients are likely driven by variable influences of dietary, psychological, and bowel dysfunction. Further studies are needed to identify mechanisms and titrate treatment suited to specific mechanistic drivers.

AbstractGhrelin is a gut hormone processed from the proghrelin peptide acting as the endogenous ligand of the GH secretagogue receptor 1a. The regulatory role of endogenous ghrelin on pulsatile GH secretion and linear growth had to be established. The aim of the present study was to delineate the endogenous actions of preproghrelin on peripheral and central components of the GH axis. Accordingly, the ultradian pattern of GH secretion was measured in young and old preproghrelin-deficient males. Blood samples were collected by tail bleeding every 10 minutes over a period of 6 hours. Analysis of the GH pulsatile pattern by deconvolution showed that GH was secreted in an ultradian manner in all genotypes, with major secretory peaks occurring at about 3-hour intervals. In older mice, the peak number was reduced and secretion was less irregular compared with younger animals. Remarkably, in young Ghrl−/− mice, the amplitude of GH secretory bursts was significantly reduced. In older mice, however, genotype differences were less significant. Changes in GH pulsatility in young Ghrl−/− mice were associated with a tendency for reduced GH pituitary contents and plasma IGF-I concentrations, but with only a minor impact on linear growth. In Ghrl+/− mice, despite reduced Acyl ghrelin to des-acyl ghrelin ratio, GH secretion was not impaired. Ghrelin deficiency was not associated with a reduction in hypothalamic GHRH content or altered response to GHRH stimulation. Therefore, reduction in GHRH production and/or sensitivity do not primarily account for the altered GH pulsatile secretion of young Ghrl−/− mice. Instead, GHRH expression was elevated in young but not old Ghrl−/− mice, suggesting that differential compensatory responses resulting from the absence of endogenous ghrelin is occurring according to age. These results show that endogenous ghrelin is a regulator of GH pulse amplitude in growing mice but does not significantly modulate linear growth.