Clinical information. Demographic and clinical information will be collected on admission.The data include age, gender, traditional risk factors for stroke (hypertension, diabetes, hyperlipidemia, smoking and coronary heart disease), medication history (anti-hypertensives, anti-diabetics, anti-platelets and statins) and other comorbidities. Hypertension is defined as previous use of antihypertensive medication, systolic blood pressure ≥140 mmHg or diastolic BP ≥90 mmHg at discharge, diabetes as previous use of antidiabetic medication or fasting blood glucose ≥126 mg/dL, and hyperlipidemia as previous use of lipid-lowering agents, fasting serum total cholesterol ≥240 mg/dL or low-density lipoprotein ≥160 mg/dL. With regard to cigarette smoking, subjects will be classified as current, former, or non-smokers. Number of pack-years will be noted for former and current smokers. History of coronary heart disease is defined as previous angina pectoris, myocardial infarction, or coronary artery bypass grafting. Patients will also be asked about any other comorbid diseases.