title: Vitamin D supplementation reduces relapse rate in relapsing-remitting multiple sclerosis patients treated with natalizumab.
abstract: BACKGROUND
  Vitamin D insufficiency is common among multiple sclerosis patients, and hypovitaminosis D has been associated with multiple sclerosis (MS) risk and disease activity.
  
  
  OBJECTIVE
  To investigate how recommendations on vitamin D3 supplements affect 25-hydroxyvitamin D (25(OH)D) levels in patients with relapsing-remitting MS (RRMS) and to examine the clinical effects associated with changes in 25(OH)D levels.
  
  
  METHODS
  In this prospective cohort study, baseline blood samples were collected from 170 natalizumab-treated RRMS patients during winter 2009-2010 and were repeated the following winter. Vitamin D supplements were recommended according to standard clinical practice in our clinic to patients with serum 25(OH)D<50nmol/l at baseline. Information was obtained on annualized relapse-rate (ARR) the year prior to baseline and the following year.
  
  
  RESULTS
  We found that recommending vitamin D supplements in patients with vitamin D insufficiency was associated with a significant increase in serum 25(OH)D concentrations (p=5.1×10-10), which was significantly related with decreases in ARR; for each nmol/l increase in Δ25(OH)D a -0.014 (95% CI -0.026 to -0.003) decrease in ΔARR was observed, p=0.02.
  
  
  CONCLUSIONS
  Correction of hypovitaminosis D in clinical practice by recommending oral D3 supplements resulted in increases in 25(OH)D levels in serum, which were associated with decreases in ARR in RRMS.
authors.affiliation: Rigshospitalet, Copenhagen University Hospital, Danish Multiple Sclerosis Center, Department of Neurology, Blegdamsvej 9, 2100 Copenhagen, Denmark. Electronic address: juliehejgaard@hotmail.com.
authors.forename: Julie Hejgaard
authors.initials: JH
authors.lastname: Laursen
authors.affiliation: Rigshospitalet, Copenhagen University Hospital, Danish Multiple Sclerosis Center, Department of Neurology, Blegdamsvej 9, 2100 Copenhagen, Denmark.
authors.forename: Helle Bach
authors.initials: HB
authors.lastname: Søndergaard
authors.affiliation: Rigshospitalet, Copenhagen University Hospital, Danish Multiple Sclerosis Center, Department of Neurology, Blegdamsvej 9, 2100 Copenhagen, Denmark.
authors.forename: Per Soelberg
authors.initials: PS
authors.lastname: Sørensen
authors.affiliation: Rigshospitalet, Copenhagen University Hospital, Danish Multiple Sclerosis Center, Department of Neurology, Blegdamsvej 9, 2100 Copenhagen, Denmark.
authors.forename: Finn
authors.initials: F
authors.lastname: Sellebjerg
authors.affiliation: Rigshospitalet, Copenhagen University Hospital, Danish Multiple Sclerosis Center, Department of Neurology, Blegdamsvej 9, 2100 Copenhagen, Denmark.
authors.forename: Annette Bang
authors.initials: AB
authors.lastname: Oturai
mesh_terms: D000328:Adult; D001774:Blood Chemical Analysis; D019587:Dietary Supplements; D004185:Disability Evaluation; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007155:Immunologic Factors / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D020529:Multiple Sclerosis, Relapsing-Remitting / Q000097:blood / Q000150:complications / Q000178:diet therapy* / Q000188:drug therapy*; D000069442:Natalizumab / Q000627:therapeutic use*; D011446:Prospective Studies; D012008:Recurrence; D012621:Seasons; D016896:Treatment Outcome; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood / Q000627:therapeutic use; D014808:Vitamin D Deficiency / Q000097:blood / Q000150:complications / Q000178:diet therapy; D055815:Young Adult
chemical_list: D007155:Immunologic Factors; D000069442:Natalizumab; D014807:Vitamin D; C104450:25-hydroxyvitamin D
keywords: 25-hydroxyvitamin D; Annualized relapse-rate; Immunomodulation; Multiple sclerosis; Vitamin D3 supplement