Antioxidant supplements and cognition in Multiple Sclerosis: a systematic review

Abstract

Background: Cognitive dysfunction is a debilitating characteristic of multiple sclerosis (MS) that affects approximately 60% of patients. To date, the only effective treatments for cognitive decline are cognitive rehabilitation and exercise training. While previous studies reported the beneficial effect of antioxidants on MS patients, several other studies investigated the effect of antioxidant supplements on the cognitive performance of MS patients. We aimed to conduct a systematic review to examine whether there is an association between antioxidants supplements and cognitive performance in MS patients. Methods: We searched PubMed, Embase, Scopus, and Web of Science for the identification of relevant studies in November 2021. We included control trials, cohort, case-control, and crosssectional studies which showed the effect of any type of antioxidants on cognitive performance in MS patients. Results: After screening 12 papers were included in our study. Our review included three studies that examined the effect of ginkgo Biloba on cognitive performance, two examined the Mediterranean diet, and remained studies each investigated the vitamin A, Omega 5, Omega 3, estriol, epigallocatechin-3-gallate (EGCG), Boswellia papyrifera, and paleolithic diet. Overall, it seems that there were no benefits for antioxidant administration on cognitive performance in MS patients. Conclusion: It is complicated to draw a conclusion regarding the effect of an antioxidantcontaining regimen and cognitive performance in MS patients. Findings from included studies failed to unequivocally support the beneficial effect of antioxidant consumption on cognitive performance in MS patients.