title: Effects of Exercise Therapy on Postural Instability in Parkinson Disease: A Meta-analysis.
abstract: OBJECTIVE
  Exercise therapy is a common intervention for improving postural stability. The purpose of this meta-analysis was to assess the effect of exercise therapy on postural instability in persons with Parkinson disease (PD) based on the available literature, and to evaluate the efficacy across various types of exercise interventions.
  
  
  METHODS
  In January 2015, electronic databases (PubMed, Scopus, PEDro) and study reference lists were searched for randomized controlled trials with moderate or high methodological quality (PEDro score ≥ 5), investigating the effect of exercise on postural instability in persons with PD.
  
  
  METHODS
  Three reviewers extracted data and assessed quality.
  
  
  METHODS
  Postural stability as measured using the Berg Balance Scale, postural sway, Timed Up and Go, or Functional Reach test. Standardized mean differences (SMDs) with 95% confidence intervals (CIs) were calculated.
  
  
  RESULTS
  Twenty-two trials, with a total of 1072 participants, were eligible for inclusion. The pooled estimates of effects showed significantly improved postural instability (SMD, 0.23; 95% CI, 0.10-0.36; P < 0.001) after exercise therapy, in comparison with no exercise or sham treatment. Exercise interventions specifically addressing components of balance dysfunction demonstrated the largest efficacy, with moderate to high effect sizes (SMD, 0.43; 95% CI, 0.21-0.66; P < 0.001). Little or no beneficial effects were observed for interventions not specifically targeted at postural stability (SMD, 0.20; 95% CI -0.04 to 0.44; P = 0.11) or for home-based, multicomponent exercise programs (SMD, 0.02; 95% CI -0.20 to 0.25; P = 0.86).
  
  
  CONCLUSIONS
  Exercise therapies specifically addressing balance dysfunction are an important treatment option for improving postural stability in persons with PD. Future studies should investigate sustainability of the short-term effects and establish the dose-response relationship of balance training in persons with PD.Video abstract available for additional insights from the authors (see Video, Supplemental Digital Content 1, http://links.lww.com/JNPT/A121).
authors.affiliation: Institute of Sport Science and Sport, Chair of Exercise and Health, Friedrich-Alexander University Erlangen-Nürnberg (FAU), Erlangen, Germany.
authors.forename: Sarah
authors.initials: S
authors.lastname: Klamroth
authors.forename: Simon
authors.initials: S
authors.lastname: Steib
authors.forename: Surendar
authors.initials: S
authors.lastname: Devan
authors.forename: Klaus
authors.initials: K
authors.lastname: Pfeifer
mesh_terms: D005081:Exercise Therapy / Q000379:methods*; D006801:Humans; D017063:Outcome Assessment, Health Care / Q000706:statistics & numerical data*; D010300:Parkinson Disease / Q000534:rehabilitation*; D004856:Postural Balance / Q000502:physiology*