Researchers at University of California, San Francisco, and State University of New York at Stony Brook, NY consecutively recruited patients with pediatric-onset multiple sclerosis into a prospective cohort to determine if vitamin D status is associated with the rate of subsequent clinical relapses. Among 110 patients followed, the mean serum 25-hydroxyvitamin D level was 22 +/- 9 ng/ml, and only 16 (15%) had normal unadjusted levels (> 30 ng/ml). After adjustment for age, gender, race, ethnicity, disease duration, therapy, and length of follow-up, every 10 ng/ml increase in adjusted 25-hydroxyvitamin D level was associated with a 34% decrease in the rate of subsequent relapses (p=0.024). Only Hispanic ethnicity was independently associated with an increased risk of relapse. The finding suggests that supplementation of vitamin D stores may reduce risk of multiple sclerosis relapse and warrants investigation. 
COMMENT. Low vitamin D levels are associated with an increased relapse rate in pediatric-onset multiple sclerosis. Relapse rate in pediatric-onset is significantly higher than that in adult-onset cases . Mean age of the patients in the above study at time of blood collection was 15 years +/- SD3.