The risk of stroke following coronary revascularization -- a population-based long-term follow-up study

OBJECTIVE: To study the incidence and risk factors of stroke after coronary artery bypass grafting (CABG) or percutaneous transluminal coronary angioplasty (PTCA). DESIGN: During 1983-1992, coronary revascularization procedures (n = 2160) were recorded in patients aged 35-64 years as part of the population-based FINMONICA Myocardial Infarction Register. The FINMONICA Stroke Register and National Hospital Discharge Register were used to ascertain subsequent stroke events in such patients. RESULTS: During the average follow-up of 5.83 years, 155 patients (7.2%) had a stroke. The cumulative incidence of stroke was 1.55% in the first year after revascularization and varied between 0.8 and 1.4% during subsequent years. In Cox proportional hazard models the relative risk of stroke was 3.01 (p = 0.0007) for a previous stroke, 2.61 (p = 0.0001) for diabetes mellitus, 2.15 (p = 0.007) for low income (compared with high income), 2.06 (p = 0.03) for male sex, and 1.43 (p = 0.02) for a 10-year increment in age. CONCLUSION: The incidence of stroke during the first year after revascularization was five times higher than among the age- and sex-matched general population. Patients with a previous stroke, diabetes mellitus, advanced age, male sex and low socioeconomic status need special attention because of increased risk of stroke after CABG or PTCA.