Multiple sclerosis patients have a diminished serologic response to vitamin D supplementation compared to healthy controls.
Vitamin D insufficiency is a risk factor for multiple sclerosis (MS), and patients do not always show the expected response to vitamin D supplementation.



We aimed to determine if vitamin D supplementation leads to a similar increase in serum 25-hydroxyvitamin-D (25(OH)D) levels in patients with MS and healthy controls (HCs).



Participants in this open-label study were female, white, aged 18-60 years, had 25(OH)D levels ⩽ 75 nmol/l at screening, and had relapsing-remitting MS (RRMS) or were HCs. Participants received 5000 IU/day of vitamin D3 for 90 days. Utilizing generalized estimating equations we examined the relationship between the primary outcome (serum 25(OH)D level) and the primary (MS versus HC status) and secondary predictors.



For this study 27 MS patients and 30 HCs were enrolled. There was no significant difference in baseline 25(OH)D level or demographics except for higher body mass index (BMI) in the MS group (25.3 vs. 23.6 kg/m(2), p=0.035). In total, 24 MS subjects and 29 HCs completed the study. In a multivariate model accounting for BMI, medication adherence, and oral contraceptive use, MS patients had a 16.7 nmol/l (95%CI: 4.2, 29.2, p=0.008) lower increase in 25(OH)D levels compared with HCs.



Patients with MS had a lower increase in 25(OH)D levels with supplementation, even after accounting for putative confounders.
Department of Neurology, Johns Hopkins University, Baltimore, MD, USA.
Pavan
P
Bhargava
Department of Neurology, Johns Hopkins University, Baltimore, MD, USA.
Sonya U
SU
Steele
Department of Neurology, University of California San Francisco, San Francisco, CA, USA.
Emmanuelle
E
Waubant
Department of Neurology, University of California San Francisco, San Francisco, CA, USA.
Nisha R
NR
Revirajan
Department of Neurology, University of California San Francisco, San Francisco, CA, USA.
Jacqueline
J
Marcus
Department of Neurology, Johns Hopkins University, Baltimore, MD, USA.
Marieme
M
Dembele
Department of Neurology, Johns Hopkins University, Baltimore, MD, USA.
Sandra D
SD
Cassard
Department of Pediatrics, Medical University of South Carolina, Charleston, SC, USA.
Bruce W
BW
Hollis
Department of Biostatistics, Johns Hopkins School of Public Health, Baltimore, MD, USA.
Ciprian
C
Crainiceanu
Department of Neurology, Johns Hopkins University, Baltimore, MD, USA emowry1@jhmi.edu.
Ellen M
EM
Mowry
D000328:Adult; D002762:Cholecalciferol / Q000008:administration & dosage / Q000494:pharmacology*; D019587:Dietary Supplements; D005260:Female; D006801:Humans; D008875:Middle Aged; D020529:Multiple Sclerosis, Relapsing-Remitting / Q000097:blood* / Q000188:drug therapy*; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood
D014807:Vitamin D; D002762:Cholecalciferol; C104450:25-hydroxyvitamin D
Multiple sclerosis; nutrition; pharmacokinetics; vitamin D supplementation