From NEJM Journal Watch/Physician's First Watch, March 8, 2016:
Low Vitamin D in Pregnancy and Increased MS Risk in Offspring: New Study Supports Potential Link
By Amy Orciari Herman
Edited by David G. Fairchild, MD, MPH, and Jaye Elizabeth Hefner, MD
Markedly deficient vitamin D levels during pregnancy are associated with increased risk for multiple sclerosis in one's offspring, suggests a case-control study in JAMA Neurology.
Using the Finnish Maternity Cohort, researchers identified nearly 200 young adults with confirmed MS and over 300 unaffected controls. Serum samples from participants' mothers, collected during pregnancy, were assessed for 25-hydroxyvitamin D (25[OH]D).
The average maternal 25(OH)D level was considered insufficient in both groups, and was somewhat lower among case mothers than controls (13.86 vs. 15.02 ng/mL). In multivariable-adjusted analyses of a subset of participants matched for region and date of birth, "clearly deficient" maternal 25(OH)D levels (<12.02 ng/mL) were associated with a near doubling of risk for MS in offspring, compared with higher levels.
An editorialist discusses potential mechanisms, including the possibility that vitamin D deficiency during myelinogenesis could lead to "weak myelin" that is particularly susceptible to the damage seen in MS.
Dr. Robert Naismith of NEJM Journal Watch Neurology notes: "While it is too early to recommend vitamin D during pregnancy for the prevention of MS, some groups are advocating for the more routine use of vitamin D within a pregnant population for a variety of potential health benefits."