title: Creatine for Parkinson's disease.
abstract: BACKGROUND
  Parkinson's disease is one of the most common neurodegenerative disorders and mitochondrial dysfunction plays an important role in its pathogenesis. Creatine is effective in improving mitochondrial function. It may therefore be useful for slowing the progression of Parkinson's disease.
  
  
  OBJECTIVE
  To assess the efficacy and safety of creatine used alone or as an adjuvant treatment for Parkinson's disease.
  
  
  METHODS
  We searched the Cochrane Movement Disorders Group Trials Register, CENTRAL (The Cochrane Library 2013, November Issue 4), MEDLINE (January 1966 to 10 November 2013), EMBASE (1974 to 10 November 2013) and two Chinese databases. We searched ongoing trials registers and conference proceedings, checked reference lists and contacted authors of included trials.
  
  
  METHODS
  Randomized controlled trials (RCTs) comparing creatine versus placebo for Parkinson's disease.
  
  
  METHODS
  Two review authors independently selected the trials for inclusion, assessed trial quality and extracted data.
  
  
  RESULTS
  We included two RCTs with a total of 194 patients. Both trials compared creatine with placebo for Parkinson's disease and both had methodological limitations. There was no clear evidence of an effect on motor function (MD -0.26; 95% confidence interval (CI) -4.39 to 3.88, low quality evidence), activities of daily living (MD 0.37; 95% CI -1.28 to 2.02, low quality evidence) or quality of life after one or two years of treatment. One trial reported serious adverse events that were not attributed to creatine. Also, one trial observed higher rates of gastrointestinal effects at two years follow-up.
  
  
  CONCLUSIONS
  The evidence base on the effects of creatine in Parkinson's disease is limited by risk of bias, small sample sizes and short duration of the eligible trials. It does not provide a reliable basis on which treatment decisions can be made. Future well-designed RCTs with larger sample size and long-term follow-up are needed to assess creatine for Parkinson's disease.
authors.affiliation: Department of Neurology, The First Affiliated Hospital, Guangxi Medical University, No. 22, Shuang Yong Lu, Nanning, Guangxi, China, 530021.
authors.forename: Yousheng
authors.initials: Y
authors.lastname: Xiao
authors.forename: Man
authors.initials: M
authors.lastname: Luo
authors.forename: Hongye
authors.initials: H
authors.lastname: Luo
authors.forename: Jin
authors.initials: J
authors.lastname: Wang
mesh_terms: D000203:Activities of Daily Living; D003401:Creatine / Q000627:therapeutic use*; D006801:Humans; D018696:Neuroprotective Agents / Q000627:therapeutic use*; D010300:Parkinson Disease / Q000188:drug therapy*; D011788:Quality of Life; D016032:Randomized Controlled Trials as Topic
chemical_list: D018696:Neuroprotective Agents; D003401:Creatine