Colon to Rectum
Gut. 2022;71(11):2226–32
Diet or medication in primary care patients with IBS: The DOMINO study – A randomized trial supported by the Belgian Health Care Knowledge Center (KCE Trials Program) and the Rome Foundation Research Institute
Background: In Europe, irritable bowel syndrome (IBS) is commonly treated with musculotropic spasmolytics (e.g., otilonium bromide, OB). In tertiary care, a low fermentable oligo-, di-, monosaccharides and polyols (FODMAP) diet provides significant improvement. Yet, dietary treatment remains to be explored in primary care. The authors evaluated the effect of a smartphone FODMAP-lowering diet application versus OB on symptoms in primary care IBS.
Methods: IBS patients, recruited by primary care physicians, were randomized to 8 weeks of OB (40 mg 3 times a day) or diet and followed for 24 weeks. IBS Symptom Severity Score and the proportion of responders (improvement ≥ 50 points) was compared in all patients and the subgroup fulfilling Rome IV criteria (Rome+). The authors also evaluated treatment efficacy, quality of life, anxiety, depression, somatic symptom severity (Patient Health Questionnaire [PHQ15, PHQ9]) and treatment adherence and analyzed predictors of response.
Results: 459 primary care IBS patients (41 ± 15 years, 76% female, 70% Rome+) were randomized. The responder rate after 8 weeks was significantly higher with diet compared with OB (71% [155/218] vs. 61% [133/217], p = 0.03) and more pronounced in Rome+ (77% [118/153] vs. 62% [98/158], p = 0.004). Patients allocated to diet (199/212) were 94% adherent compared with 73% with OB (148/202) (p < 0.001). The significantly higher response rate with diet was already observed after 4 weeks (62% [132/213] vs. 51% [110/215], p = 0.02) and a high symptom response persisted during follow-up. Predictors of response were female gender (odds ratio = 2.08, p = 0.04) for diet and PHQ15 (odds ratio = 1.10, p = 0.02) for OB.
Conclusion: In primary care irritable bowel syndrome (IBS) patients, a FODMAP-lowering diet application was superior to a spasmolytic agent in improving IBS symptoms. A FODMAP-lowering diet should be considered the first-line treatment for IBS in primary care.