title: Vitamin D and white matter abnormalities in older adults: a cross-sectional neuroimaging study.
abstract: OBJECTIVE
  Morphological brain changes related to hypovitaminosis D have been poorly studied. In particular, the age-related decrease in vitamin D concentrations may explain the onset of white matter abnormalities (WMA) in older adults. Our objectives were (i) to investigate whether there was an association between serum 25-hydroxyvitamin D (25OHD) concentration and the grade of WMA in older adults and (ii) to determine whether the location of WMA was associated with 25OHD concentration.
  
  
  METHODS
  One hundred and thirty-three Caucasian older community-dwellers with no clinical hydrocephalus (mean 71.6 ± 5.6 years; 43.6% female) received a blood test and a magnetic resonance imaging scan of the brain. The grades of total, periventricular and deep WMA were scored using semiquantitative visual rating scales from T2-weighted fluid-attenuated inversion recovery images. The association of WMA with as-measured and deseasonalized 25OHD concentrations was evaluated with the following covariates: age, gender, body mass index, use of anti-vascular drugs, number of comorbidities, impaired mobility, education level, Mini-Mental State Examination score, medial temporal lobe atrophy, serum concentrations of calcium, thyroid-stimulating hormone and vitamin B12, and estimated glomerular filtration rate.
  
  
  RESULTS
  Both as-measured and deseasonalized serum 25OHD concentrations were found to be inversely associated with the grade of total WMA (adjusted β = -0.32, P = 0.027), specifically with periventricular WMA (adjusted β = -0.15, P = 0.009) but not with deep WMA (adjusted β = -0.12, P = 0.090). Similarly, participants with 25OHD concentration <75 nM had on average a 33% higher grade of periventricular WMA than those with 25OHD ≥75 nM (P = 0.024). No difference in average grade was found for deep WMA (P = 0.949).
  
  
  CONCLUSIONS
  Lower serum 25OHD concentration was associated with higher grade of WMA, particularly periventricular WMA. These findings provide a scientific basis for vitamin D replacement trials.
authors.affiliation: Department of Neuroscience, Division of Geriatric Medicine, University Memory Clinic, Angers University Hospital, Angers, France; UPRES EA4638, University of Angers, UNAM, Angers, France; Department of Medical Biophysics, Robarts Research Institute, Schulich School of Medicine and Dentistry, University of Western Ontario, London, ON, Canada.
authors.forename: C
authors.initials: C
authors.lastname: Annweiler
authors.forename: T
authors.initials: T
authors.lastname: Annweiler
authors.forename: R
authors.initials: R
authors.lastname: Bartha
authors.forename: F R
authors.initials: FR
authors.lastname: Herrmann
authors.forename: R
authors.initials: R
authors.lastname: Camicioli
authors.forename: O
authors.initials: O
authors.lastname: Beauchet
mesh_terms: D000368:Aged; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D056784:Leukoencephalopathies / Q000097:blood* / Q000473:pathology*; D008279:Magnetic Resonance Imaging; D008297:Male; D059906:Neuroimaging; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000097:blood
chemical_list: D014807:Vitamin D; C104450:25-hydroxyvitamin D
keywords: brain; leukoaraiosis; magnetic resonance imaging; older adults; vitamin D; white matter