Treatment efficacy of a low FODMAP diet compared to a low lactose diet in IBS patients: A randomized, cross-over designed study.

BACKGROUND AND OBJECTIVE: A low FODMAP diet (LFD) has become a standard treatment in irritable bowel syndrome (IBS) patients. Compliant adherence to a LFD is challenging. We investigated the effect of a LFD compared to a less restrictive low lactose diet (LLD) in a randomized cross-over trial with IBS patients. METHODS: Twenty-nine IBS patients were randomly assigned to two groups. After a run-in phase of 14 days, patients received 21 days of either a LFD or LLD. This intervention was followed by a washout period of 21 days before crossing over to the alternate diet. Dietician led diet instruction was given continuously. An IBS Severity Scoring System (IBS-SSS) was filled in at the end of each study period. To enhance study adherence, daily symptoms were assessed using a Visual Analog Scale (VAS). RESULTS: IBS patients, irrespective of lactase deficiency, had a significantly reduced IBS-SSS score after both diets (LFD p = 0.002, LLD p = 0.007) without significant difference. On both diets, patients reported that IBS had less impact on their daily life compared to the time before the study (p < 0.01). On daily assessment, IBS patients on LFD reported significantly less abdominal pain (median VAS difference to baseline -0.8 (-2.8 to 2.7, p = 0.03) and less bloating (-0.5 (-4.1 to 3.4, p = 0.02) than patients on the LLD. CONCLUSION: Both diets improved the overall IBS severity significantly and patients' preference of the two diets was similar. LFD but not LLD effectively reduced pain and bloating in patients with IBS.

Manometric Subtypes of Ineffective Esophageal Motility.

OBJECTIVES: Ineffective esophageal motility (IEM) is characterized by well-defined manometric criteria. However, much variation exists within the diagnosis: Some patients exhibit exactly the required five weak swallows to make the diagnosis. Others show consistently ineffective swallows with total absence of any normal swallow. "We hypothesize" there are two different manometric subtypes of IEM; IEM Alternans (IEM-A) and IEM Persistens (IEM-P). METHODS: A total of 231 IEM patients were identified by high-resolution manometry (HRM). IEM defined by distal contractile integral (DCI) <450 mm Hg/s/cm in ≥50% of test swallows. Abnormal reflux study was defined by excess total number of reflux episodes, abnormal esophageal acid exposure, or positive symptom association. RESULTS: A total of 195 (84%) patients had IEM-A and 36 (16%) had IEM-P. A striking gender difference with 34% of IEM-A being males compared to 53% of IEM-P. (P=0.03). Mean age of IEM-P (59.6 years+/-13.1) was greater than IEM-A (55.5 years+/-13.6) (P=0.04). Mean lower esophageal sphincter (LES) resting pressure was significantly lower in IEM-P (20.8 mm Hg+/-1.4) than IEM-A (29 mm Hg+/-1.2) (P=0.002). There was no difference in LES-integrated relaxation pressure (IRP), bolus transit, or manometric presence of hiatal hernia between the two groups. Out of 146, 89 (61%) patients had abnormal reflux study. Esophageal acid exposure in upright position was significantly higher in IEM-P than IEM-A (3.5 vs. 1.7%, P=0.04). Poor gastric acid control on proton pump inhibitor (PPI) was more prevalent among IEM-P patients (58%) than IEM-A (27%) (P=0.007). In subgroup analysis of 41 IEM patients with dysphagia, DCI for liquid swallows was significantly lower in IEM-P (111+/-142 mm Hg/s/cm) compared to IEM-A (421+/-502 mm Hg/s/cm) (P=0.04), lower mean LES resting pressure in IEM-P (16.6+/-9 mm Hg) than IEM-A (31.7+/-18 mm Hg) (P=0.01). CONCLUSIONS: There are two distinct manometric IEM subtypes; IEM-P with an older male predominance, more advanced reflux disease, weaker LES, and worse response to PPI; likely a more advanced manifestation than IEM-A. However, the question if there are different etiologies underlying the two subtypes remains to be answered.