Thyroid hormone linked to MS development

A recent study suggests that elevated levels of the thyroid hormone free thyroxine (FT4) are linked to an increased the risk of developing multiple sclerosis (MS).

They found elevated thyroid-stimulating hormone (TSH) levels and hypothyroidism appeared linked to a reduced risk. However, further analyses indicated that only FT4 had a causal relationship with MS risk.

The study also examined whether MS could influence thyroid function and found no significant effect of MS on FT4 levels, suggesting that elevated FT4 is more likely a contributing factor to MS rather than a consequence. Further investigation revealed that specific immune cells, particularly those marked by CD33 and influenced by human leukocyte antigen (HLA) genes, may mediate the relationship between FT4 and MS. Interestingly, a subset of B-cells lacking CD27 and immunoglobulin D markers might offer a protective effect against MS in the context of altered FT4 levels.

These findings highlight a complex interplay between thyroid hormones and immune system components in the development of MS, underscoring the need for further research into potential therapeutic targets within these pathways.