Initiating multi-strain probiotics is associated with clinically meaningful symptom relief, better quality of life, and fewer treatment escalations in IBS-D/IBS-M: a Chinese real-world propensity-matched cohort study.

INRODUCTION: Evidence for probiotics in irritable bowel syndrome remains heterogeneous, although real-world use is common in Chinese gastroenterology practice. This study evaluated whether initiation of multi-strain probiotics, compared with contemporary standard care without probiotics, was associated with clinically meaningful symptom and quality-of-life improvement in adults with diarrhoea-predominant or mixed irritable bowel syndrome. METHODS: This single-centre retrospective real-world cohort study identified adults with Rome IV IBS-D or IBS-M managed between January 2022 and December 2024 from electronic health records. A new-user design with a symmetrical 14-day landmark was used. After prespecified exclusions, 287 patients comprised the full analytic set, including 122 probiotic initiators and 165 non-users. One-to-one nearest-neighbour propensity score matching yielded 75 matched pairs. Outcomes were assessed at 4-6 and 8-12 weeks, with change in IBS Symptom Severity Score from baseline to 8-12 weeks as the primary endpoint. RESULTS: In the matched cohort, probiotic initiation was associated with a greater reduction in IBS-SSS than standard care at 8-12 weeks, with mean changes of -95 versus -60 points and a mean difference of -35 points (95% CI: -50 to -20; p = 0.001). IBS-SSS response occurred more frequently with probiotics than with non-use (62.7% versus 44.0%), as did pain response (58.7% versus 40.0%) and adequate relief (54.7% versus 38.7%). IBS-QOL improved by 16.0 versus 8.0 points, and IBS-QOL minimal clinically important difference response was more frequent with probiotics (53.3% versus 34.7%). Adverse events were infrequent and similar between groups (16.0% versus 13.3%). Treatment escalation occurred less often with probiotics (24.0% versus 40.0%). DISCUSSION: In routine Chinese hospital care, initiation of multi-strain probiotics was associated with earlier and clinically meaningful symptom improvement, better disease-specific quality of life, and fewer treatment escalations among adults with IBS-D or IBS-M, without an apparent excess of adverse events.