title: Effect of coenzyme Q₁₀ supplementation on heart failure: a meta-analysis.
abstract: BACKGROUND
  Coenzyme Q₁₀ (CoQ₁₀; also called ubiquinone) is an antioxidant that has been postulated to improve functional status in congestive heart failure (CHF). Several randomized controlled trials have examined the effects of CoQ₁₀ on CHF with inconclusive results.
  
  
  OBJECTIVE
  The objective of this meta-analysis was to evaluate the impact of CoQ₁₀ supplementation on the ejection fraction (EF) and New York Heart Association (NYHA) functional classification in patients with CHF.
  
  
  METHODS
  A systematic review of the literature was conducted by using databases including MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials, and manual examination of references from selected studies. Studies included were randomized controlled trials of CoQ₁₀ supplementation that reported the EF or NYHA functional class as a primary outcome. Information on participant characteristics, trial design and duration, treatment, dose, control, EF, and NYHA classification were extracted by using a standardized protocol.
  
  
  RESULTS
  Supplementation with CoQ₁₀ resulted in a pooled mean net change of 3.67% (95% CI: 1.60%, 5.74%) in the EF and -0.30 (95% CI: -0.66, 0.06) in the NYHA functional class. Subgroup analyses showed significant improvement in EF for crossover trials, trials with treatment duration ≤12 wk in length, studies published before 1994, and studies with a dose ≤100 mg CoQ₁₀/d and in patients with less severe CHF. These subgroup analyses should be interpreted cautiously because of the small number of studies and patients included in each subgroup.
  
  
  CONCLUSIONS
  Pooled analyses of available randomized controlled trials suggest that CoQ₁₀ may improve the EF in patients with CHF. Additional well-designed studies that include more diverse populations are needed.
authors.affiliation: Department of Medicine, School of Medicine, Tulane University, New Orleans, LA 70112, USA. dfotino@tulane.edu
authors.forename: A Domnica
authors.initials: AD
authors.lastname: Fotino
authors.forename: Angela M
authors.initials: AM
authors.lastname: Thompson-Paul
authors.forename: Lydia A
authors.initials: LA
authors.lastname: Bazzano
mesh_terms: D000328:Adult; D019587:Dietary Supplements; D006333:Heart Failure / Q000178:diet therapy* / Q000503:physiopathology; D006801:Humans; D016032:Randomized Controlled Trials as Topic; D012720:Severity of Illness Index; D013318:Stroke Volume; D014451:Ubiquinone / Q000031:analogs & derivatives* / Q000627:therapeutic use; D018487:Ventricular Dysfunction, Left / Q000209:etiology / Q000517:prevention & control*
chemical_list: D014451:Ubiquinone; C024989:coenzyme Q10