title: Hypovitaminosis D in Delirium: a Retrospective Cross-sectional Study.
abstract: BACKGROUND
  As vitamin D may have a neuroprotective effect, the authors studied the association of biomarkers of vitamin D status and delirium to see if low vitamin D status was common in delirium cases.
  
  
  METHODS
  Biochemical measures of vitamin D (25-hydroxyvitamin D [25-OHD]) and calcium metabolism were used in this retrospective cross-sectional analysis of adult in-patients with delirium, admitted at three Canadian academic hospitals from January 2011 to July 2012. Primary outcome was to determine estimates of the prevalence of hypovitaminosis D in this group in whom vitamin D was checked.
  
  
  RESULTS
  Seventy-one (5.8%) out of 1,232 delirium inpatients had their vitamin D measured. Thirty-nine (55%) showed vitamin D insufficiency (25-OHD of 25-75 nmol/L) and 8 (11%) showed vitamin D deficiency (25-OHD < 25 nmol/L). Mean serum 25-OHD levels were lower in males (57.1±7.7 nmol/L) than in females (78.2±6.1 nmol/L), p = .01, even when controlled for age and season. Men were younger than the women (74.4±2.3 vs. 82.4±1.7, p = .005). Mean age was 78.7±1.5 years, and 33 (47%) were male.
  
  
  CONCLUSIONS
  Although vitamin D is rarely checked during delirium workup and/or management, high rates of hypovitaminosis D were found to be common in the delirium in-patients in whom it was checked. Larger studies would be needed to estimate the prevalence of hypovitaminosis D in delirium and whether hypovitaminosis D plays a role in the pathogenesis of delirium.
authors.affiliation: Department of Psychiatry and Behavioural Neurosciences, Michael G. DeGroote School of Medicine, Faculty of Health Sciences, McMaster University, Hamilton, ON, Canada;
authors.forename: Jennifer
authors.initials: J
authors.lastname: Ford
authors.forename: Ana
authors.initials: A
authors.lastname: Hategan
authors.forename: James A
authors.initials: JA
authors.lastname: Bourgeois
authors.forename: Daniel K
authors.initials: DK
authors.lastname: Tisi
authors.forename: Glen L
authors.initials: GL
authors.lastname: Xiong
keywords: acute care; acute in-patient; delirium; vitamin D; vitamin D insufficiency