Bloating in Irritable Bowel Syndrome Is Associated with Symptoms Severity, Psychological Factors, and Comorbidities

Bloating is one of the most bothersome symptoms of irritable bowel syndrome (IBS), but its association with other symptoms is not well described.

We investigated the association between symptoms of abdominal bloating, other IBS symptoms, psychological distress, and comorbid pain conditions.

We conducted a cross-sectional study on a large cohort of IBS patients with and without symptoms of abdominal bloating and healthy controls. Subjects were assessed for IBS and its subtypes, pain severity, symptoms severity, psychological disturbances, comorbidities, and dietary restrictions of three fluid groups.

A total of 484 subjects were investigated. Compared with IBS - B, IBS + B subjects had higher rates of constipation (30% vs. 15%, p = 0.191) and lower rates of diarrhea, (70% vs. 85%, p = 0.191) although these were not statistically significant. Bloating severity correlated with IBS symptoms severity (r = 0.397, p = 0.000), pain severity (r = 0.364, p = 0.000), and both anxiety and somatization scores (r = 0.167, p = 0.015 and r = 0.219, p = 0.001, respectively). Prevalence of fibromyalgia and depression and somatization scores was significantly higher in IBS with bloating than in IBS without bloating. IBS patients with bloating reported more dietary restriction of three fluid groups to control their symptoms compared with healthy controls and IBS patients without bloating.

Abdominal bloating in IBS is associated with increased symptoms and pain severity, somatization, depression, fibromyalgia, and altered dietary fluids composition. Recognizing and addressing these factors in the diagnosis and management of patients with IBS may improve clinical outcome.