Coffee consumption and risk of multiple sclerosis: A systematic review and meta-analysis

Background: Multiple Sclerosis (MS) is an immune-mediated disease with miscellaneous etiological origins. Given caffeine's neuroprotective and anti-inflammatory attributes and its potential influence on MS risk, and to address the conflict in the clinical evidence, this study aims to comprehensively review the existing literature on the association between coffee consumption and the risk of MS. Methods: Following the PRISMA 2020 guidelines, a systematic search in PubMed, Scopus, Web of Science, and Embase for the studies published up to January 2024 was conducted. Studies that assessed the relationship between coffee intake and the risk of MS were included, and reviews, case reports, non-English papers, in vitro and animal studies, and conference abstracts were excluded. The risk of bias was assessed using the JBI checklists, and meta-analyses were conducted based on odds ratio (OR) using the fourth version of CMA software. Results: Out of 604 initial records, 10 observational studies with 19,430 participants met the inclusion criteria. The included case-control studies showed an overall high quality. Meta-analysis revealed a reduction in MS development in coffee consumers both before (OR: 0.66; 95 % CI: 0.49-0.90; p-value: 0.008; I-2: 89.65 %; p-value for heterogeneity<0.001) and after adjustment for possible confounders (adjusted OR: 0.42; 95 % CI: 0.20-0.90; p-value: 0.025; I-2: 89.65 l; p-value for heterogeneity<0.001). Conclusion: Coffee consumption, may decrease the risk of MS; however, further well-designed prospective studies are required to ascertain this association.