Follow-up of patients with functional bowel symptoms treated with a low FODMAP diet

To investigate patient-reported outcomes from, and adherence to, a low FODMAP diet among patients suffering from irritable bowel syndrome and inflammatory bowel disease.

Consecutive patients with irritable bowel syndrome (IBS) or inflammatory bowel disease (IBD) and co-existing IBS fulfilling the ROME III criteria, who previously attended an outpatient clinic for low FODMAP diet (LFD) dietary management and assessment by a gastroenterologist, were invited to participate in a retrospective questionnaire analysis. The questionnaires were sent and returned by regular mail and gathered information on recall of dietary treatment, efficacy, symptoms, adherence, satisfaction, change in disease course and stool type, and quality of life. Before study enrolment all patients had to sign an informed written consent.

One hundred and eighty patients were included, 131 (73%) IBS and 49 (27%) IBD patients. Median age was 43 years (range: 18-85) and 147 (82%) were females. Median follow-up time was 16 mo (range: 2-80). Eighty-six percent reported either partial (54%) or full (32%) efficacy with greatest improvement of bloating (82%) and abdominal pain (71%). The proportion of patients with full efficacy tended to be greater in the IBD group than in the IBS group (42% vs 29%, P = 0.08). There was a significant reduction in patients with a chronic continuous disease course in both the IBS group (25%, P < 0.001) and IBD group (23%, P = 0.002) along with a significant increase in patients with a mild indolent disease course of 37% (P < 0.001) and 23% (P = 0.002), respectively. The proportion of patients having normal stools increased with 41% in the IBS group (P < 0.001) and 66% in the IBD group (P < 0.001). One-third of patients adhered to the diet and high adherence was associated with longer duration of dietary course (P < 0.001). Satisfaction with dietary management was seen in 83 (70%) IBS patients and 24 (55%) IBD patients. Eighty-four percent of patients lived on a modified LFD, where some foods rich in FODMAPs were reintroduced, and 16% followed the LFD by the book without deviations. Wheat, dairy products, and onions were the foods most often not reintroduced by patients.

These data suggest that a diet low in FODMAPs is an efficacious treatment solution in the management of functional bowel symptoms for IBS and IBD patients.