Antioxidant enzyme activity and coronary heart disease: meta-analyses of observational studies

Am J Epidemiol. 2009 Jul 15;170(2):135-47. doi: 10.1093/aje/kwp112. Epub 2009 May 22.


Controversial data exist concerning the relation between the activities of scavenger antioxidant enzymes and coronary heart disease (CHD) risk. The authors report updated meta-analyses of studies assessing the activities of 3 antioxidant enzymes--glutathione peroxidase, superoxide dismutase, and catalase--and CHD risk. Computer-based and manual searches of the relevant literature from January 1966 to January 2008 were performed. Studies assessing glutathione peroxidase, superoxide dismutase, and catalase activities in cells or biologic fluids and clinical CHD outcomes were selected. Pooled odds ratios for CHD were calculated by using an inverse-variance-weighted random-effects model. Forty-two case-control studies and 3 prospective studies were included. The pooled odds ratios for CHD associated with a 1-standard-deviation increase in glutathione peroxidase, superoxide dismutase, and catalase activity levels were 0.51 (95% confidence interval: 0.35, 0.75), 0.48 (95% confidence interval: 0.32, 0.72), and 0.32 (95% confidence interval: 0.16, 0.61), respectively, with substantial between-study heterogeneity (I(2) > 90% for the 3 enzymes). These findings were remarkably robust in the sensitivity analysis. The authors' meta-analyses support an inverse association between circulating levels of superoxide dismutase, glutathione peroxidase, and catalase activities with CHD and emphasize the need for additional high-quality prospective studies.

Publication types

  • Meta-Analysis

MeSH terms

  • Catalase / metabolism*
  • Confidence Intervals
  • Coronary Artery Disease / enzymology*
  • Glutathione Peroxidase / metabolism*
  • Humans
  • Odds Ratio
  • Oxidative Stress*
  • Reactive Oxygen Species*
  • Risk Factors
  • Superoxide Dismutase / metabolism*


  • Reactive Oxygen Species
  • Catalase
  • Glutathione Peroxidase
  • Superoxide Dismutase