All patients who underwent cardiac catheterization for assessment of CAD at Keelung Chang Gung Memorial Hospital between 1992 and 2004 with continuous serum creatinine values measured before admission were included in this analysis. Data were obtained from medical records of the database center of our institution. Demographic and clinical data were assessed. The age, sex, body mass index (BMI), body surface area (BSA), underlying comorbidities, CAD risk factors (including diabetes mellitus, hypertension, dyslipidemia, smoking, and obesity, defined as a BMI \> 30) and clinical presentation were included in this study. Hemodynamic parameters including the systolic and diastolic blood pressure, heart rate and left ventricular ejection fraction were also obtained. Coronary angiography was performed using a low-osmolarity non-ionic contrast medium (iodixanol) by experienced cardiologist. Coronary artery disease was defined as a 50% or greater lumen narrowing of a major epicardial artery or its branches. A left main stenosis of 50% or greater was regarded as equivalent to 2-vessel disease. Blood samples were collected during admission before angiographic procedure. Values of hemoglobin, white blood cells, platelet, high sensitivity C-reactive protein (hs-CRP) and troponin I was included. The treatment modality was divided into three categories: medical, percutaneous coronary intervention (PCI, including balloon angioplasty with or without stent placement) and coronary artery bridge graft (CABG) on the basis of clinical condition and angiographic finding. The outcome was followed-up until 12 months after angiographic procedure. The estimated total study patient number is approximately 1000 patients.