The effects of probiotic Saccharomyces boulardii on the mental health, quality of life, fatigue, pain, and indices of inflammation and oxidative stress in patients with multiple sclerosis: study protocol for a double-blind randomized controlled clinical trial

BACKGROUND: The relationship between gut dysbiosis and inflammatory diseases including multiple sclerosis (MS) is presently recognized as an important health issue. It has been established that some bacterial probiotic strains are effective in treating MS. This study will investigate the effect of yeast probiotic Saccharomyces boulardii (SB) supplements on mental health, quality of life, fatigue, pain, and indices of inflammation and oxidative stress in MS patients. METHODS/DESIGN: In this double-blind randomized controlled two-group parallel trial, 50 MS patients who meet the inclusion criteria will be recruited from outpatient settings. They will be randomly allocated to 4 months of daily placebo or the SB probiotic intervention. Blood samples will be taken from each participant at the baseline and after the intervention period to assess inflammation and oxidative stress. The primary endpoint will be the changes in their mental health evaluated by the 28-item General Health Questionnaire. The secondary endpoints include changes in: (1) quality of life, evaluated by the 36-item Short Form Questionnaire, (2) fatigue, evaluated by the Fatigue Severity Scale, (3) pain, evaluated by a visual analogue scale, and (4) serum levels of indices of inflammatory stress (high-sensitivity C-reactive protein) and oxidative stress (malondialdehyde and total antioxidant capacity). Moreover, any adverse events and side effects due to the intervention will be documented. DISCUSSION: There is a need to discover safe and practical methods for managing the symptoms of MS. This trial will gather evidence on the effects of a probiotic. TRIAL REGISTRATION: Iranian Clinical Trial Registry, IRCT20161022030424N1. Registered on 9 April 2018. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1186/s13063-019-3454-9) contains supplementary material, which is available to authorized users.