title: Efficacy of menatetrenone (vitamin K2) against non-vertebral and hip fractures in patients with neurological diseases: meta-analysis of three randomized, controlled trials.
abstract: OBJECTIVE
  Patients with neurological diseases such as Alzheimer's disease, stroke and Parkinson's disease have been reported to have vitamin K deficiency secondary to malnutrition, which increases the risk of non-vertebral and hip fractures. The purpose of the present study was to clarify the efficacy of menatetrenone (vitamin K(2)) against non-vertebral and hip fractures in patients with neurological diseases.
  
  
  METHODS
  A literature search was conducted on PubMed from January 1995 to July 2008 to identify randomized controlled trials (RCTs) of use of menatetrenone against non-vertebral and hip fractures in patients with neurological diseases. A meta-analysis of all RCTs meeting these criteria was then performed.
  
  
  RESULTS
  Three RCTs of patients with Alzheimer's disease (n = 178, mean age 78 years), stroke (n = 99, mean age 66 years) and Parkinson's disease (n = 110, mean age 72 years) met the criteria for meta-analysis. These RCTs did not include placebo controls but did have non-treatment controls. According to the meta-analysis, the overall relative risks (95% confidence intervals) for non-vertebral and hip fractures with menatetrenone treatment compared with non-treatment were 0.13 (0.05, 0.35) and 0.14 (0.05, 0.43), respectively, in patients with neurological diseases. No severe adverse events were reported with menatetrenone treatment.
  
  
  CONCLUSIONS
  The present meta-analysis of three RCTs suggests that there is efficacy for menatetrenone treatment against non-vertebral and hip fractures among patients with neurological diseases. Further larger placebo-controlled trials are needed to confirm the results of the present study.
authors.affiliation: Institute for Integrated Sports Medicine, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan. jiwamoto@sc.itc.keio.ac.jp.
authors.forename: Jun
authors.initials: J
authors.lastname: Iwamoto
authors.affiliation: Institute for Integrated Sports Medicine, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan.
authors.forename: Hideo
authors.initials: H
authors.lastname: Matsumoto
authors.affiliation: Institute for Integrated Sports Medicine, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan.
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Takeda
mesh_terms: D000368:Aged; D050071:Bone Density Conservation Agents / Q000627:therapeutic use*; D001927:Brain Diseases / Q000150:complications*; D005260:Female; D050723:Fractures, Bone / Q000150:complications* / Q000188:drug therapy*; D006620:Hip Fractures / Q000150:complications / Q000188:drug therapy; D006801:Humans; D008297:Male; D016032:Randomized Controlled Trials as Topic; D024482:Vitamin K 2 / Q000031:analogs & derivatives* / Q000627:therapeutic use
chemical_list: D050071:Bone Density Conservation Agents; D024482:Vitamin K 2; C030814:menatetrenone