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Background: Bifidobacterium longum 35624 has shown efficacy in improving irritable bowel syndrome (IBS) symptoms compared with placebo in double-blind randomized studies. However, few data are available from real-life clinical practice or from studies that used Rome IV criteria to diagnose IBS.

Aim: To assess the effect of B. longum 35624 on IBS severity and quality of life in a real-life setting.

Methods: From November 2018 to January 2020, 278 patients with IBS (according to Rome IV criteria) were enrolled in a prospective, open-label, multicenter observational study by private practice gastroenterologists to received one capsule of B. longum 35624 (109 colony-forming units) per day for 30 d. Participation in the study was independently proposed to patients during spontaneous consultations. Disease severity (assessed by the IBS severity scoring system) and patient quality of life (assessed by the IBS quality of life questionnaire) were compared between the inclusion visit (baseline) and the visit at the end of 30 d of treatment. The characteristics of patients were described at baseline. Continuous variables comparisons between inclusion and end-of-treatment visits were performed using the t-test and Kruskal-Wallis test. Categorical variables comparisons were performed using the χ2 test.

Results: A total of 233 patients, with a mean age of 51.4 years and composed of 71.2% women, were included in the study. Of these patients, 48.1% had moderate IBS and 46.4% had severe IBS. After a 30-d treatment period with one B. longum 35624 capsule per day, a significant decrease in IBS severity was observed compared to baseline (mean ± SD, IBS severity scoring system scores: 208 ± 104 vs 303 ± 81, P < 0.001) and 57% of patients moved to lower severity categories or achieved remission. The quality of life of patients was also improved by the treatment (IBS Quality of Life questionnaire score: 68.8 ± 20.9 vs 60.2 ± 20.5; P < 0.001) and 63.8% of patients were satisfied with the treatment.

Conclusion: Thirty days of treatment with B. longum 35624 reduces disease severity and improves the quality of life of patients with IBS, particularly those with the most severe forms of IBS.

Keywords: Abdominal pain; Bifidobacterium longum; Irritable bowel syndrome; Probiotics; Quality of life; Severity of illness index.

Research Insights

SupplementHealth OutcomeEffect TypeEffect Size
Bifidobacterium longum iVE-15Improved Quality of LifeBeneficial
Bifidobacterium longum iVE-15Reduced IBS SeverityBeneficial
Bifidobacterium longum subsp. longum 35624Improved Quality of LifeBeneficial
Bifidobacterium longum subsp. longum 35624Improved SatisfactionBeneficial
Bifidobacterium longum subsp. longum 35624Reduced IBS SeverityBeneficial
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