ABSTRACT: BACKGROUND:The aim of the current study was to evaluate the association of PAI-1 4G/5G polymorphism with coronary artery disease (CAD) risk using a meta-analysis. METHODS:All eligible studies were identified through a search of PubMed, EMBASE, China National Knowledge Infrastructure (CNKI), Database of Chinese Scientific and Technical Periodicals, and China Biology Medical literature database (CBM) before June 2014. The association between the PAI-1 4G/5G polymorphism and CAD risk was estimated by odds ratio (OR) and 95% confidence interval (CI). RESULTS:A total of 72 studies including 23557 cases and 21526 controls were eventually collected. The PAI-1 4G/5G polymorphism was significant associated with CAD risk in overall population (OR=1.19, 95% CI 1.10-1.28, P < 0.00001). The combination of adjusted ORs for CAD was 1.20 (95% CI 1.03-1.40, P=0.02). This polymorphism was associated with CAD risk in Caucasians (OR=1.10, 95% CI 1.02-1.19, P=0.01) and Asians (OR=1.46, 95% CI 1.21-1.75, P < 0.0001). This polymorphism significantly increased MI risk (OR=1.15, 95% CI 1.06-1.25, P=0.001). In the subgroup analysis by age, this polymorphism was significantly associated with early-onset CAD risk (OR=1.21, 95% CI 1.02-1.43, P=0.03). In the gender subgroup analyses, a statistically significant association was found in male CAD patients (OR=1.10, 95% CI 1.01-1.20, P=0.04). Both T2DM patients and non-T2DM patients carrying 4G allele showed increased CAD risks (OR=2.23, 95% CI 1.27-3.92, P=0.005 and OR=1.64, 95% CI 1.19-2.25, P=0.002, respectively). CONCLUSIONS:This meta-analysis suggested that PAI-1 4G/5G polymorphism was a risk factor for CAD.