S1130 Real-World Effectiveness of the Low FODMAP Diet vs Other Therapeutic Diet Interventions for Functional Gastrointestinal Disorders, Under Guidance of a Registered Dietitian

Introduction: A low fermentable oligosaccharides, disaccharides, monosaccharides and polyols diet (LFD) is commonly used to improve gastrointestinal (GI) symptoms for patients with a variety of functional GI disorders (FGID), including irritable bowel syndrome (IBS). The LFD is not straightforward, and data suggests that using an experienced dietitian to implement this diet increases success. The aim of this study was to assess the effectiveness of LFD in real world GI practice with an embedded dietitian and to compare this to other dietary interventions employed for these disorders. Methods: Adult patients seen in a gastroenterology practice with a dedicated registered dietitian between 1/1/2021 to 12/31/2023 who were referred to the dietitian with a diagnosis where a LFD was considered were evaluated for eligibility. Cases were patients who underwent a LFD trial while controls were those who decided along with the dietitian to not undertake a LFD and instead underwent other dietary changes (avoiding trigger foods, augmenting fiber intake, improving mealtime habits). Patients already on a LFD or without adequate follow up were excluded. Symptoms were categorized into 8 groups based on the GI PROMIS symptom scale and assessed pre- and post-intervention. Results: We identified 58 cases and 144 controls. Of cases, 48 (83%) successfully completed phase 1 of the LFD, 14 (24%) phase 2, and 3 (5.2%) phase 3. The most common symptoms were gas/bloating (82%), abdominal pain (66%), and diarrhea (50%). At baseline, both groups had a similar number of symptoms (3.17 vs 2.95, P = 0.17). By 6 months, both had similar rates of having at least 1 symptom improved (40% vs 36%, P = 0.64) and at least 1 symptom resolved (28% vs 22.9%, P = 0.48). The overall number of symptoms resolved was similar (0.51 vs 0.38, P = 0.34). Success rates of improving individual symptoms were also similar, except for the control group having greater improvement in reflux symptoms. Conclusion: Most patients who pursued the LFD were able to successfully complete the first phase under dietitian guidance. Over half of the patients who completed the LFD achieved improvement in at least 1 symptom. Those who opted for alternative diet interventions, demonstrated improvements in symptoms at rates similar to those who had pursued the LFD. This data suggests that, while the LFD is an effective therapeutic approach to FGID, patients who are unable or unwilling to follow a LFD can still benefit from other therapeutic diet adjustments, under the careful management of a dietitian.