title: Vitamin A and systemic inflammation as protective factors in multiple sclerosis.
abstract: BACKGROUND
  Vitamin A is important for the immune system, and might suppress inflammatory activity in multiple sclerosis (MS).
  
  
  OBJECTIVE
  We aimed to examine if vitamin A levels were associated with MS risk in samples collected prospectively and during gestation.
  
  
  METHODS
  We measured Retinol Binding Protein (RBP--a surrogate marker for vitamin A) and high-sensitivity C-reactive protein (hs-CRP) levels, in (1) prospectively collected biobank blood samples from MS cases and controls, and (2) gestational samples where the offspring had later developed MS, and gestational control samples. The risk of MS was calculated using matched multivariable logistic regression adjusted for confounders.
  
  
  RESULTS
  In prospective samples, RBP levels within the second quintile (vs. the first) were associated with a lower MS risk (OR = 0.38, 95% CI 0.19-0.74). No effect on MS risk in the offspring by gestational RBP levels was found. In young subjects hs-CRP levels ≥10 mg/l in prospective samples were associated with a lower MS risk (OR = 0.36, 95% CI 0.14-0.95).
  
  
  CONCLUSIONS
  Our results suggest that sub-optimal vitamin A levels may be associated with MS risk. The association between hs-CRP levels and MS risk in young subjects may support the role of the hygiene hypothesis in MS aetiology.
authors: Department of Pharmacology and Clinical Neuroscience, Section of Neurology at Umeå University, Sweden. jonatan.salzer@neuro.umu.se
authors: Jonatan
authors: J
authors: Salzer
authors: Göran
authors: G
authors: Hallmans
authors: Maria
authors: M
authors: Nyström
authors: Hans
authors: H
authors: Stenlund
authors: Göran
authors: G
authors: Wadell
authors: Peter
authors: P
authors: Sundström
mesh_terms: D000293:Adolescent; D000328:Adult; D002097:C-Reactive Protein / Q000032:analysis; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D007249:Inflammation / Q000378:metabolism*; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000097:blood*; D011247:Pregnancy; D012177:Retinol-Binding Proteins / Q000032:analysis; D014801:Vitamin A / Q000032:analysis*; D055815:Young Adult
chemical_list: D012177:Retinol-Binding Proteins; D014801:Vitamin A; D002097:C-Reactive Protein
keywords: CRP; Multiple sclerosis; c-reactive protein; case-control study; hygiene hypothesis; retinol; risk factors in epidemiology; vitamin a