title: Vitamin D is associated with degree of disability in patients with fully ambulatory relapsing-remitting multiple sclerosis.
abstract: OBJECTIVE
  Vitamin D deficiency is a recognized risk factor for multiple sclerosis (MS) and is associated with increased disease activity. It has also been proposed that the lower the vitamin D levels are, the higher is the handicap.
  
  
  METHODS
  To refine the links between vitamin D insufficiency and disability in MS patients, a retrospective cohort analysis was performed including 181 patients prospectively followed without previous vitamin D supplementation, and age, gender, age at MS onset, MS type, MS activity, Expanded Disability Status Scale (EDSS) were analysed in correlation with plasma vitamin D levels.
  
  
  RESULTS
  Vitamin D levels were significantly higher in relapsing-remitting MS than in progressive forms of MS in multivariate analyses adjusted for age, ethnicity, gender, disease duration and season (P = 0.0487). Overall, there was a negative correlation between vitamin D level and EDSS score (P = 0.0001, r = -0.33). In relapsing-remitting MS, vitamin D levels were only correlated with disability scores for EDSS < 4 (P = 0.0012). Patients with >20 ng/ml of vitamin D were 2.78 times more likely to have an EDSS < 4 (P = 0.0011, 95% confidence interval 1.49-5.00).
  
  
  CONCLUSIONS
  Data support previous work suggesting that vitamin D deficiency is associated with higher risk of disability in MS. Vitamin D levels also correlated with the degree of disability in fully ambulatory patients with relapsing-remitting MS. These additional results support the pertinence of randomized controlled trials analysing the interest of an early vitamin D supplementation in MS patients to influence evolution of disability.
authors.affiliation: Neurology Department, CHRU Caremeau, Nîmes, France; Institut de Génomique Fonctionnelle, UMR5203, Université Montpellier 1 et 2, Montpellier, France.
authors.forename: E
authors.initials: E
authors.lastname: Thouvenot
authors.forename: M
authors.initials: M
authors.lastname: Orsini
authors.forename: J-P
authors.initials: JP
authors.lastname: Daures
authors.forename: W
authors.initials: W
authors.lastname: Camu
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D020528:Multiple Sclerosis, Chronic Progressive / Q000097:blood* / Q000503:physiopathology*; D020529:Multiple Sclerosis, Relapsing-Remitting / Q000097:blood* / Q000503:physiopathology*; D012189:Retrospective Studies; D012720:Severity of Illness Index; D014807:Vitamin D / Q000097:blood*
chemical_list: D014807:Vitamin D
keywords: Expanded Disability Status Scale; disability; multiple sclerosis; multiple sclerosis severity score; vitamin D