title: Vitamin K₂ alters bone metabolism markers in hemodialysis patients with a low serum parathyroid hormone level.
abstract: BACKGROUND
  A low level of intact parathyroid hormone (PTH) is an indicator of adynamic bone disease in hemodialysis patients, and is associated with a significant increase of all-cause mortality. Thus, effective treatment for adynamic bone disease is required. We previously investigated the effect of vitamin K₂ on adynamic bone disease. In this study, we assessed the efficacy of oral vitamin K₂ in a controlled trial.
  
  
  METHODS
  Forty hemodialysis patients with low intact PTH levels (<100 pg/ml) were randomly divided into two groups, which were a vitamin K₂ group receiving oral menatetrenone (45 mg/day) for 1 year and a control group without vitamin K₂. Venous blood samples were collected at baseline and during the study for measurement of bone metabolism parameters.
  
  
  RESULTS
  Thirty-three patients completed follow-up. There was a significant increase of the serum intact osteocalcin level after 1 month of vitamin K₂ administration. Serum levels of intact PTH, bone alkaline phosphatase, and cross-linked N-terminal telopeptide of type I collagen increased significantly after 12 months in the vitamin K₂ group. The serum osteoprotegerin level was decreased after 12 months in the vitamin K₂ group, but the change was not significant.
  
  
  CONCLUSIONS
  Vitamin K₂ therapy improves bone remodeling in hemodialysis patients with a low intact PTH level.
authors.affiliation: Department of Advanced Nephrology, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima, Japan.
authors.forename: Mariko
authors.initials: M
authors.lastname: Ochiai
authors.forename: Ayumu
authors.initials: A
authors.lastname: Nakashima
authors.forename: Norihisa
authors.initials: N
authors.lastname: Takasugi
authors.forename: Kei
authors.initials: K
authors.lastname: Kiribayashi
authors.forename: Toru
authors.initials: T
authors.lastname: Kawai
authors.forename: Koji
authors.initials: K
authors.lastname: Usui
authors.forename: Kenichiro
authors.initials: K
authors.lastname: Shigemoto
authors.forename: Naoki
authors.initials: N
authors.lastname: Hamaguchi
authors.forename: Nobuoki
authors.initials: N
authors.lastname: Kohno
authors.forename: Noriaki
authors.initials: N
authors.lastname: Yorioka
mesh_terms: D000368:Aged; D000469:Alkaline Phosphatase / Q000097:blood; D015415:Biomarkers / Q000097:blood; D001847:Bone Diseases / Q000209:etiology* / Q000378:metabolism*; D016723:Bone Remodeling / Q000187:drug effects; D024042:Collagen Type I / Q000097:blood; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015675:Osteocalcin / Q000097:blood; D010281:Parathyroid Hormone / Q000097:blood*; D010455:Peptides / Q000097:blood; D006435:Renal Dialysis / Q000009:adverse effects*; D018709:Statistics, Nonparametric; D024482:Vitamin K 2 / Q000031:analogs & derivatives* / Q000494:pharmacology / Q000627:therapeutic use
chemical_list: D015415:Biomarkers; D024042:Collagen Type I; D010281:Parathyroid Hormone; D010455:Peptides; C052929:collagen type I trimeric cross-linked peptide; D015675:Osteocalcin; D024482:Vitamin K 2; C030814:menatetrenone; D000469:Alkaline Phosphatase