title: A low vitamin D status at diagnosis is associated with an early conversion to secondary progressive multiple sclerosis.
abstract: Low circulating 25-hydroxyvitamin D (25(OH)D) levels have been associated with an increased risk of relapses in relapsing remitting multiple sclerosis (RRMS), but an association with disability progression is uncertain. Lower 25(OH)D levels are found in secondary progressive MS (SPMS) when compared to RRMS. We hypothesized that a poor vitamin D status in RRMS is associated with an increased risk of conversion to SPMS. In a retrospective longitudinal study we measured 25(OH)D levels at the start of a 3-year follow-up, and analyzed whether these levels predict the risk of RRMS to SPMS conversion. In 338 RRMS patients, vitamin D status did not predict the 3-year risk of conversion to SPMS (n=51; OR 0.970; p=0.65). However, in diagnostic blood samples of SPMS patients with a relatively short RRMS duration (n=19) 25(OH)D levels were significantly lower (38nmol/L; Q1-Q3: 24-50) than in diagnostic samples of matched RRMS patients with no progression to SPMS ((n=38; 55nmol/L; Q1-Q3: 40-70) (p<0.01). These data indicate an association between a low vitamin D status at the start of RRMS and the early conversion to SPMS. Therefore, time to SPMS conversion is of interest as clinical measure in (follow-up of) clinical vitamin D supplementation studies.
authors.affiliation: School for Mental Health and Neuroscience, Maastricht University Medical Center, Maastricht, The Netherlands; Academic MS Center Limburg, Zuyderland Medical Center, Sittard, The Netherlands. Electronic address: a.muris@maastrichtuniversity.nl.
authors.forename: Anne-Hilde
authors.initials: AH
authors.lastname: Muris
authors.affiliation: School for Mental Health and Neuroscience, Maastricht University Medical Center, Maastricht, The Netherlands; Academic MS Center Limburg, Zuyderland Medical Center, Sittard, The Netherlands.
authors.forename: Linda
authors.initials: L
authors.lastname: Rolf
authors.affiliation: Clinical Chemistry, Zuyderland Medical Center, Sittard, The Netherlands.
authors.forename: Kelly
authors.initials: K
authors.lastname: Broen
authors.affiliation: School for Mental Health and Neuroscience, Maastricht University Medical Center, Maastricht, The Netherlands; Academic MS Center Limburg, Zuyderland Medical Center, Sittard, The Netherlands.
authors.forename: Raymond
authors.initials: R
authors.lastname: Hupperts
authors.affiliation: Central Diagnostic Laboratory, Maastricht University Medical Center, Maastricht, The Netherlands.
authors.forename: Jan
authors.initials: J
authors.lastname: Damoiseaux
authors.affiliation: Academic MS Center Limburg, Zuyderland Medical Center, Sittard, The Netherlands; Department of Neurology, Canisius Wilhelmina Hospital, Nijmegen, The Netherlands.
authors.forename: Joost
authors.initials: J
authors.lastname: Smolders
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000097:blood; D018450:Disease Progression; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D020528:Multiple Sclerosis, Chronic Progressive / Q000097:blood / Q000175:diagnosis* / Q000473:pathology; D020529:Multiple Sclerosis, Relapsing-Remitting / Q000097:blood / Q000175:diagnosis* / Q000473:pathology; D011379:Prognosis; D012189:Retrospective Studies; D012307:Risk Factors; D013997:Time Factors; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood
chemical_list: D015415:Biomarkers; D014807:Vitamin D; C104450:25-hydroxyvitamin D
keywords: 25-Hydroxyvitamin D; Disability; Relapsing remitting multiple sclerosis; Secondary progressive multiple sclerosis; Vitamin D