the effects of probiotic supplementation on level of disability, depressive symptoms, and cognitive outcomes in relapsing-remitting multiple sclerosis patients: a randomized double-blind placebo-controlled trial

Background: multiple sclerosis (ms) is a chronic autoimmune disease characterized by inflammation and demyelination of the central nervous system. probiotics, through the gut-brain axis, are suggested to enhance clinical outcomes in patients with ms. this study scrutinizes the effects of probiotic supplementation in relapsing-remitting ms (rrms) patients. methods: in this parallel, randomized, double-blind, placebo-controlled trial, 90 rrms patients, with expanded disability status scale (edss) < 4, received either the probiotic (lactocare®) or a placebo twice daily for four months. assessed outcomes included level of disability (based on edss), cognitive function (symbol digit modalities test [sdmt], three-second version of paced auditory serial addition test [pasat-3]), depressive symptoms (beck depression inventory- ii [bdi-ii]), and manual dexterity (nine-hole peg test [9hpt]). blinding was performed for outcome assessors and the patients. all assessments were conducted at baseline and after four months, and the findings compared between the groups of the study. results: out of 90 randomized patients, 60 completed the trial (29 in the probiotics group, 31 in the placebo group). probiotics supplementation was not associated with significant improvement in edss, bdi-ii, pasat, sdmt, and non-dominant hand 9hpt (p-values > 0.05). intragroup improvements in pasat-3 (change median: 2 [iqr:9.5]) and dominant hand 9hpt (change median: -0.43 [iqr: 2.15]) were observed in the probiotic supplementation group, which was comparable to placebo. conclusion: supplementation with a seven-strain probiotics product for four months does not result in a significant improvement in depressive symptoms, cognitive performance, level of disability, and manual dexterity of rrms patients with edss < 4.