Clinical Characteristics of Coronary Heart Disease as Predictors of Ischemic Stroke: A Long-term Prospective Follow-up in the BIP Study.
Objective: To assess characteristics and severity of coronary heart disease (CHD) predisposing to ischemic stroke, beyond conventional vascular risk factors. Methods: We prospectively followed up 3,122 patients with documented CHD included in a secondary prevention trial of lipid modification, the Bezafibrate Infarction Prevention trial. Patients had CHD documented by a history of myocardial infarction ≥6 months and <5 years before enrollment and/or stable angina pectoris confirmed by ancillary diagnostic testing, and a selected lipid profile. Patients with severe heart failure or unstable angina upon enrollment were excluded. Results: During a mean follow-up period of 8.2 years, 186 patients developed an ischemic stroke. The rate of ischemic stroke was 8.8% among patients with an active anginal syndrome[class ≥2 according to the Canadian Cardiovascular Society angina Classification, (CCSC)]vs. 5.1% in patients with a CCSC class of 1 (p<0.001). Patients with heart failure according to class ≥2 of the New York Heart Association classification had a 7.7% rate of ischemic stroke vs. 5.5% among patients with a class of 1 (no limitation of physical activity; p=0.03). In a Cox Proportional Hazard model adjusting for conventional risk factors, CCSC angina class ≥2 remained an independent predictor of ischemic stroke (Hazard ratio 1.43; 95%CI 1.05–1.96) and hospitalization for a confirmed diagnosis of unstable angina during follow-up conferred an additional independent increased risk (Hazard ratio 1.7; 95%CI 1.04–2.87). Hazard ratios of conventional risk factors, for comparison, where 1.49 for a 10 year age increment, 2.29 for diabetes mellitus, 1.75 for current smoking, 1.81 for peripheral vascular disease, and 1.14 for a 10 mmHg increase in systolic blood pressure. Conclusion: Active angina (CCSC class ≥2)and hospitalization for unstable angina during follow-up among CHD patients,confer an independent increased risk of ischemic stroke, beyond conventional vascular risk factors.