Predictive value of cystatin C in people with suspected or established coronary artery disease: A meta-analysis.

BACKGROUND AND AIMS: Circulating cystatin C has been recognized as an independent predictor of cardiovascular and all-cause mortality in the general population. We aimed to evaluate the prognostic value of baseline circulating cystatin C levels in people with suspected or established coronary artery disease (CAD) by conducting a meta-analysis.

METHODS: We searched Pubmed and Embase databases up to October 2016 for prospective observational studies investigating the predictive value of elevated circulating cystatin C levels in people with suspected or established CAD. Adverse vascular outcomes included all-cause mortality, cardiovascular mortality, or total adverse vascular events consisting of death, myocardial infarction, revascularization, stroke, and heart failure.

RESULTS: Ten studies involving participants with known or suspected CAD were included in this meta-analysis. When comparing the highest with the lowest cystatin C levels, the pooled hazard ratio (HR) was 2.27 (95% confidence interval [CI] 1.86-2.78) for all-cause mortality, 2.24 (95% CI 1.69-2.97) for cardiovascular mortality, and 1.87 (95% CI 1.57-2.24) for total adverse vascular events, respectively. Subgroup analysis results showed that this association was not influenced by follow-up duration, region, or CAD type.

CONCLUSIONS: Elevated circulating cystatin C is independently associated with adverse vascular outcomes in people with suspected or established CAD in terms of all-cause mortality, cardiovascular mortality, and total adverse vascular events. This increased risk is probably independent of creatinine/estimated glomerular filtration rate.