Vitamin D Levels May Influence Multiple Sclerosis Risk

Genetically reduced vitamin D levels could increase susceptibility to MS.

Low vitamin D levels may lead to a greater risk of developing multiple sclerosis (MS), according to observational evidence from genetic findings in a recent study.

The study, published this week in PLOS Medicine, noted that inferring a causal relationship between MS development and vitamin D levels is difficult due to an additional unknown characteristic that also may increase MS risk.

Researchers evaluated the association between genetically diminished vitamin D levels, as measured by the level of 25-hydroxyvitamin D, and multiple sclerosis susceptibility. The researchers analyzed 14,498 patients with multiple sclerosis and 24,091 healthy controls.

A genetic decrease in natural-log-transformed vitamin D level by one standard deviation was linked to a two-fold increase in the risk for developing MS. The researchers utilized a genetic technique known as Mendelian randomization to decrease the chance of confounding or reverse causation, however the results of the study may be limited by some assumptions made during the study.

Researchers still concluded that "genetically lowered vitamin D levels are strongly associated with increased susceptibility to multiple sclerosis. Whether vitamin D sufficiency can delay, or prevent, multiple sclerosis onset merits further investigation in long-term randomized controlled trials."

The authors further wrote that "ongoing randomized controlled trials are currently assessing vitamin D supplementation for the treatment and prevention of multiple sclerosis ... and may therefore provide needed insights into the role of vitamin D supplementation."