Probiotics′ Effects on Depression, High-Sensitivity C-Reactive Protein (hs-CRP), and Oxidative Stress in Patients With Multiple Sclerosis: A Meta-Analysis

Objectives: Major depressive disorder (MDD) is highly prevalent in patients with multiple sclerosis (MS). There is evidence that the gut microbiota affect the inflammatory responses and oxidative status in MS and may affect depression signs and symptoms in these patients. Based on this fact, this updated meta-analysis assessed the effect of probiotic supplementation on the Beck Depression Inventory (BDI), high-sensitivity C-reactive protein (hs-CRP), total antioxidant capacity (TAC), and malondialdehyde (MDA) in patients with MS. Methods: A systematic literature search was done for English literature through PubMed/Medline, Cochrane Library, Google Scholar, and ScienceDirect from 1 January 2011 to 1 June 2024. This study followed the PRISMA guidelines. Based on the heterogeneity, the random-effects or fixed-effects models were used in the present meta-analysis. Results: After checking for eligibility, four RCTs were included in the final analysis. There was an improvement in BDI-II score, hs-CRP level, MDA, and TAC in patients with MS (BDI-II score: MD = -2.78; 95% CI, -3.32 to -2.24; Z = 10.09; p < 0.00001; I2 = 57%; p = 0.1; hs-CRP level: MD = -1.69; 95% CI, -1.98 to -1.40; Z = 11.38; p < 0.00001; I2 = 0%; p = 0.96; MDA: MD = -0.37; 95% CI, -0.52 to -0.23; Z = 5.00; p < 0.00001; I2 = 90%; p < 0.0001; and TAC: MD = 5.48; 95% CI, -6.71 to 17.66; Z = 0.88; p = 0.38; I2 = 93%; p < 0.00001). Conclusion: This meta-analysis suggests that probiotic supplementation has improved BDI scores and inflammatory and oxidative status. This finding promises that probiotic supplementation can be considered as a therapeutic option for depression symptoms and inflammatory status in patients with MS. However, more interventional studies are required to assess the complex relationship between MS, depression, and the gut microbiome. PROSPERO Registration ID: CRD42024552648.