Aims: To study the association between renal function and outcomes in a nationwide cohort of unselected consecutive patients with stable coronary artery disease (SCAD) symptoms and with a defined coronary anatomy by a coronary angiogram (CA).
Methods and results: We included 45 348 consecutive patients with available plasma creatinine undergoing CA for suspected SCAD from the Swedish Coronary Angiography and Angioplasty Registry (SCAAR). We adjusted for clinical background, severity of CAD and subsequent revascularization in a Cox regression analysis. Patients were followed for a median (interquartile range) time of 2.6 (1.2-4.1) years. The 3-year cumulative probability of death, myocardial infarction (MI), heart failure, and stroke increased from 2.7, 4.6, 4.4, and 2.0% in patients with estimated glomerular function (eGFR) >90 to 39.8, 32.8, 30.2, and 6.2% in patients with eGFR <15. Compared with patients with eGFR > 90 mL/min/m2, patients with impaired renal function (eGFR 30-59, 15-29, and <15 mL/min/m2) had significantly higher risk of death (HR (95%CI): 1.3 (1.1-1.5), 2.2 (1.6-2.9), 7.7 (6.1-9.8)), MI (1.3 (1.1-1.5), 1.8 (1.4-2.5), 4.0 (3.1-5.1)), and heart failure (1.7 (1.5-1.9), 2.5 (1.9-3.1), 2.4 (1.8-3.2)), but not of stroke (1.1 (0.9-1.3), 1.1 (0.6-1.7), 1.4 (0.7-2.5)) after multivariable adjustment. For patients with eGFR 60-89, there was no significant difference in the risk of death, MI or stroke but increased risk of heart failure 1.2 (1.1-1.3).
Conclusion: Impaired renal function is strongly associated with worse outcome in patients with SCAD and known coronary anatomy. The associations were independent of traditional cardio vascular disease risk factors, comorbidities, coronary artery obstruction severity, and subsequent revascularization.