Pelvic floor biofeedback is an effective treatment for severe bloating in disorders of gut-brain interaction with outlet dysfunction

Background: The pathophysiology of bloating is partially understood. We investigated in patients with disorders of gut-brain interaction (DGBI) the relationship between severity of bloating, abdominal girth changes and defecation pattern, and the efficacy of pelvic floor biofeedback treatment on bloating. Methods: Disorders of gut-brain interaction patients with severe bloating as the main complaint were prescribed 2 weeks dietary advice and underwent abdominal girth measurements. At the first visit, all patients underwent a questionnaire on the subjective improvement of bloating, a (0–100) VAS abdominal bloating, and abdominal girth measurement. Patients reporting inadequate bloating relief underwent a standardized balloon expulsion test. Furthermore, they were invited to undergo pelvic floor electromyography and biofeedback treatment previously used for constipation due to dyssynergic defecation. The primary outcome was bloating improvement on a 5-point Likert scale. The secondary outcomes were the effect of diet intervention and pelvic floor biofeedback treatment on bloating severity and quality of life changes as well as the effect of pelvic floor biofeedback treatment on BET and EMG on straining. Key results: One hundred and fifty six patients (129 F, 39.3 ± 11.7 mean age) completed the 2-week run-in period. 105 patients were diet non-responder and underwent balloon expulsion test, with the vast majority (64%) failing the test. Patients who scored higher bloating on VAS had a significant association with failed balloon expulsion test (adjusted B 0.4 [95% CI 10.8–25.7], p < 0.0001). 63% agreed to perform pelvic floor biofeedback treatment at Verona center, 54% became responders reporting fair or major improvement/cure (ITT analysis, McNemar test, p < 0.0001), and all of them showed a 50% decrease in bloating severity. Conclusions and Inferences: Disordered defecation is a prevalent etiology in DGBI patients with bloating unresponsive to conservative measures; pelvic floor biofeedback treatment to improve the defecation effort significantly relieved bloating (http://www.isrctn.com, ISRCTN17004079).