Effect of fermented milk containing probiotics on symptoms in Korean adults with irritable bowel syndrome

Abstract

Background/aims Irritable bowel syndrome (IBS) is a chronic and recurrent disease, and low-grade inflammation has been known as a key factor in the pathogenesis of IBS. Using some strains of probiotics which were reported to have remarkable immunomodulatory function, we designed prospective double-blind randomized placebo-controlled clinical study to investigate the effect of fermented milk containing probiotics in Korean adults with IBS. Methods IBS patients who met Rome III criteria were randomly assigned to receive fermented milk containing functional probiotics or placebo. Total 13 billion lyophilized bacteria (Lactobacillus brevis HY7401, Lactobacillus sp. HY7801, and bifidobacterium longum HY8004) were administered three times daily for 8 weeks. Primary outcome variables were symptom scores consisting of abdominal pain, flatulence, defecation discomfort and sum of symptom scores. A 100 mm visual analogue scale was used to measure the severity. Secondary outcome variables consisted of bowel habits including frequency and form. To assess the change of small metabolites after treatment, metabolomic analysis was performed using patients serum. Results Thirty seven patients were randomized to the probiotics group and 36 to the placebo. Intention-to-treat analysis showed significant improvements after 8 weeks on defecation discomfort, -30.1 in probiotics group vs. -16.3 in placebo (P = 0.031), and sum of scores, -85.6 vs. -51.9 respectively (P = 0.022). Defecation frequency was significantly changed from baseline, -1.5 in probiotics group vs. 0.5 in placebo (P = 0.041). Metabolomic analysis showed remarkable increase of lactate in patients serum after probiotics treatment. Conclusions Fermented milk containing functional probiotics was safe and effective in IBS patients.