The Relationship Between Estimated Glomerular Filtration Rate And Coronary Atherosclerosis

Background and Objective In patients with coronary artery disease (CAD),renal dysfunction is more prevalent than that in the general population and is a major risk factor for cardiovascular death and all-cause mortality.But the association of renal function with coronary atherosclerotic burden was not been well described.Renal function is usually best evaluated by estimated glomerular filtration rate(eGFR) with formulas based on serum creatinine level and variables such as age, sex and so on.The aim of this study is to investigate the association of eGFR with coronary atherosclerotic burden.Design Retrospective observational study.Methods Glomerular filtration rate on admission was estimated using the Modification of Diet in Renal Disease equation in 1174 patients who had undergone coronary angiography.The presence of conventional atherosclerotic risk factors,coronary anatomy(from angiography),left atrium diameter,left ventricular ejection fraction,blood glucose,blood fat,CRP,NT-proBNP level and low density lipoprotein level were recorded. Patients with valvular heart disease or congenital heart defect and those underwent revascularization therapy were excluded.A narrowing of the lumen by more than 50%of the prestenotic diameter was considered to indicate clinically significant stenosis.Coronary pathological changes limits score was assessed by the number of stenotic vessels as follows:1=no vessel disease;2=one-vessel disease;3= twe-vessel disease;4=three-vessel disease.The severity of atherosclerotic changes was also assessed by grading the stenotic lesions as follows:0=luminal reduction＜25%;1=luminal reduction of 25%to 49%;2=luminal reduction of 50%to 74%;3=luminal reduction of 75% to 99%;and 4=total occlusion.The points used to grade each branch of the coronary artery were added and a coronary narrow severity score was obtained.The total coronary narrow severity score was used to reflect the severity of CAD.All patients were stratified into 4 groups according to quartiles of their baseline eGFR as group 1(eGFR＜98.89 ml/min),group 2(86.47＜eGFR≤98.89 ml/min),group 3(74.01＜eGFR≤86.47 ml/min),group 4 (eGFR≤74.01 ml/min).Baseline clinical characteristics,cardiac function and coronary atherosclerotic burden were compared among the 4 groups.The odds ratios for morbidity of three-vessel CAD,myocardial infarction and in-hospital mortality with eGFR were calculated by Logistic regression.Results Patients with eGFR levels in low group had higher rate of hypertension,diabetes,cerebrovascular accident and periphery artery disease and lower rate of male and smoking.The mean coronary pathological changes limits score and mean coronary narrow severity score in the group 4 were both greater than those in group 1(2.84±0.07 vs.2.38±0.06, P＜0.001 and 5.88±0.21vs.4.64±0.20,P＜0.001).In Spearman correlation analyse,eGFR was negative correlated with coronary pathological changes limits score(r=-0.174,P＜0.001) and coronary narrow severity score(r =-0.155,P＜0.001).In multiple Logistic regression model,eGFR (stratified by per 10 ml/min) was an independent risk factor for three-vessel CAD(the adjusted odds ratio was 0.864,95%CI:0.803-0.929), myocardial infarction(the adjusted odds ratio was 0.883,95%CI: 0.828-0.943) and in-hospital mortality(the adjusted odds ratio was 0.606, 95%CI:0.468-0.784).Conventional coronary atherosclerotic risk factors such as Age,sex,smoker,hypertension,diabetes were included as covariates in the model.Patients with eGFR levels in the group 4 had higher level of lg(NT-proBNP) and left atrium diameter than patients with eGFR levels in group 1(2.81±0.05pg/mL vs.2.21±0.04pg/mL,P＜0.001 and 40.5±0.3mm vs.38.1±0.3mm,P＜0.001).Patients with eGFR levels in the group 4 had lower left ventricular ejection fraction than patients with eGFR levels in group 1(61.8±0.7%vs.65.8±0.5%,P＜0.001).Patients with eGFR levels in the group 4 had higher lg(hs-CRP) level than patients with eGFR levels in group 1(0.58±0.06mg/L vs.0.34±0.06 mg/L,P=0.003).Conclusion Patients with lower eGFR levels have severer coronary atherosclerosis and cardiac dysfunction,eGFR is an independent risk factor for in-hospital mortality.