Vitamin D in Multiple Sclerosis: A Comprehensive Umbrella Review

Area of Science:

• Neuroimmunology
• Genetics
• Nutritional Science

Background:

• Multiple sclerosis (MS) is a complex inflammatory neuroimmune disease with significant long-term health impacts.
• Research has investigated the potential roles of 25-hydroxyvitamin D (25(OH)D) levels, vitamin D receptor (VDR) gene variations, and vitamin D supplementation (VDS) in MS.
• This study provides an umbrella review of existing evidence.

Purpose of the Study:

• To evaluate the relationship between MS and 25(OH)D serum levels.
• To assess the association of MS with VDR gene polymorphisms (Apal, BsmI, Taql, Fokl).
• To examine the role of VDS in the risk and clinical manifestations of MS.

Main Methods:

• An umbrella review of articles from PubMed, Scopus, and Web of Science up to February 24, 2024.
• Inclusion of meta-analyses examining 25(OH)D, VDR polymorphisms, and VDS in relation to MS risk and clinical features.
• Methodological quality assessed using the Assessment of Multiple Systematic Reviews 2 (AMSTAR 2); statistical analysis performed with RStudio and R.

Main Results:

• A total of 23 records, encompassing 37,567 participants, were included in the review.
• The homozygote model of the FokI VDR gene polymorphism (FF+ff vs. Ff) showed a significant 8% reduction in MS risk (OR: 0.92, 95% CI: 0.86-0.98).
• Quality assessment revealed varying levels of methodological rigor among the included studies.

Conclusions:

• Existing evidence suggests a potential association between VDR gene polymorphism and the risk of developing MS.
• Further research is warranted to elucidate the comprehensive relationship between MS and vitamin D.
• The study highlights the need for continued investigation into genetic and environmental factors influencing MS.