Background: Estimated glomerular filtration rate (eGFR) and proteinuria are both important determinants of the risk of cardiovascular disease and mortality. The aim of the present study was to investigate the independent and combined effects of eGFR and proteinuria on tissue characterization of the coronary plaques of culprit lesions.
Methods and results: Conventional intravascular ultrasound and 3-D integrated backscatter intravascular ultrasound (IB-IVUS) were performed in 555 patients undergoing elective percutaneous coronary intervention. They were divided into 2 groups according to the absence or presence of proteinuria (dipstick result ≥1+). Patients with proteinuria had coronary plaque with significantly greater percentage lipid volume compared with those without (43.6±14.8% vs. 48.6±16.1%, P=0.005). Combined analysis was done using eGFR and absence or presence of proteinuria. Subjects with eGFR 45-59 ml/min/1.73 m2 and proteinuria were significantly more likely to have higher percent lipid volume compared with those with eGFR >60 ml/min/1.73 m2 without proteinuria. After multivariate adjustment for confounders, the presence of proteinuria proved to be an independent predictor for lipid-rich plaque (OR, 1.85; 95% CI: 1.12-3.06, P=0.016).
Conclusions: The addition of proteinuria to eGFR level may be of value in the risk stratification of patients with coronary artery disease.