title: Vitamin K in hand osteoarthritis: results from a randomised clinical trial.
abstract: OBJECTIVE
  Vitamin K has bone and cartilage effects, and previously shown to be associated with radiographic osteoarthritis. We evaluated vitamin K's effect on hand osteoarthritis in a randomised controlled trial.
  
  
  METHODS
  This was an ancillary study to a randomised controlled trial assessing the effects of phylloquinone supplementation (vitamin K arm) versus placebo on bone loss and vascular calcification among older adults regardless of their vitamin K status. At the final 3-year study visit, we assessed the effects of vitamin K versus placebo on hand x-ray features of osteoarthritis using logistic regression and intention to treat, and also restricted analysis to the subgroup that had insufficient vitamin K concentrations at baseline.
  
  
  RESULTS
  This ancillary study had 378 participants (193 in vitamin K arm, 185 in placebo arm). There were no effects of randomisation to vitamin K for radiographic osteoarthritis outcomes. Those with insufficient vitamin K at baseline who attained sufficient concentrations at follow-up had trends towards 47% less joint space narrowing (p = 0.02).
  
  
  CONCLUSIONS
  There was no overall effect of vitamin K on radiographic hand osteoarthritis.
  
  
  METHODS
  that were insufficient in vitamin K at baseline who attained sufficient concentrations at follow-up may have had a benefit in joint space narrowing. A clinical trial in those who are vitamin K insufficient may be warranted.
  
  
  BACKGROUND
  NCT00183001.
authors.affiliation: Boston University School of Medicine, Boston, MA 02118, USA. tneogi@bu.edu
authors.forename: T
authors.initials: T
authors.lastname: Neogi
authors.forename: D T
authors.initials: DT
authors.lastname: Felson
authors.forename: R
authors.initials: R
authors.lastname: Sarno
authors.forename: S L
authors.initials: SL
authors.lastname: Booth
mesh_terms: D000368:Aged; D019587:Dietary Supplements; D004311:Double-Blind Method; D005260:Female; D005500:Follow-Up Studies; D050823:Hand Joints / Q000000981:diagnostic imaging* / Q000473:pathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D010003:Osteoarthritis / Q000000981:diagnostic imaging / Q000209:etiology / Q000473:pathology / Q000517:prevention & control*; D011859:Radiography; D010837:Vitamin K 1 / Q000097:blood / Q000627:therapeutic use*; D014813:Vitamin K Deficiency / Q000097:blood / Q000150:complications
chemical_list: D010837:Vitamin K 1