Vitamin D Levels Not Linked to Adult-onset Multiple Sclerosis

There is no link between vitamin D levels in newborn babies to the development of multiple sclerosis (MS) in adulthood, according to research published in the Annals of Neurology.

Researchers from the Karolinska Institutet examined 459 incident cases of MS compared with 663 control subjects, who were matched for sex, age, and residential area. Each MS patient provided a blood sample and completed a questionnaire. The patients were sourced from the EIMS project lead by the Institute of Environmental Medicine at the Karolinska Institutet in collaboration with all Swedish hospitals' neurology departments.

The initial hypothesis was set out to explore the relationship to birth dates — in the spring versus the autumn — and the development of MS in adulthood. Prior studies have shown that limited sun exposure during pregnancy produces lower vitamin D levels and could increase risk for MS development in children born after the winter.

Researchers originally intended for this study to ensure levels of vitamin D in pregnant women were not too low.

"We could not see any association between levels of vitamin D at birth and risk of MS in adulthood," said Peter Ueda, researcher at Karolinska Intitutet, said in a press release. "However, a weaker link cannot be ruled out, nor can the link be ruled out for people with certain genes."

The Karolinska researchers used a method of analyzing the dried blood samples, known as 25-hydroxy vitamin D, which was developed by Queensland, Australia, researchers. Regardless of the participants' month of birth, geographical latitude of their birth, sun exposure, and vitamin D intake in adult age, development of MS was not affected.

This was the first study of its kind, the researchers noted. Never before had researchers had access to an entire country's worth of blood samples that have been stored since participant's birth. Then, researchers would have to be able to follow the participants for about 30 years, or the average amount of time it takes for MS to develop.

"Such biobanks are uncommon; however, one can be found in Sweden," Ueda said. "This study could be conducted due to the unique possibilities for monitoring and follow-up of patients in Sweden."