Risk of Stroke After Coronary Artery Bypass Grafting

Abstract

Background and Purpose— The risk of stroke after coronary artery bypass grafting (CABG) is known to increase dramatically with age. During recent years, the age of patients operated on has increased and concomitant therapy has changed. Therefore, we have re-evaluated the risk of stroke after CABG. Methods— Through the Danish National Hospital Register, we identified all 25 159 patients with isolated CABG from 1997 through 2006. Stroke, comorbidities, and medication were further obtained. Risk factors of stroke were determined through regression models. Results— Overall, 1901 patients (7.6%) suffered a stroke after surgery, 477 patients (2.0%) within 30 days after CABG. Rates of stroke per 100 person-years (95% CI) within 30 days after surgery increased with age: <60 years, 10.1 (7.8–13.0); 60 to 64 years, 18.4 (14.3–23.5); 65 to 69 years, 27.7 (23.0–33.3); 70 to 74 years, 36.0 (30.4–42.6); 75 to 79 years, 36.1 (29.1–44.7); ≥80 years, 38.0 (25.2–57.1). Risks of stroke within 30 days after surgery adjusted for age (reference: age <60 years), sex, relevant comorbidities, and selected medication included: 60 to 64 years: HR, 1.7 ( P =0.005; 95% CI, 1.2–2.4), 65 to 69 years: HR, 2.4 ( P =0.001; 95% CI, 1.7–3.3), 70 to 74 years: HR, 2.8 ( P =0.001; 95% CI, 2.1–3.8), 75 to 79 years: HR, 2.8 ( P =0.001; 95% CI, 2.0–4.0), ≥80 years: HR, 3.0 ( P =0.001; 95% CI, 1.8–4.9), previous stroke: HR, 4.2 ( P =0.001; 95% CI, 3.3–5.4), diabetes: HR, 1.3 ( P =0.019; 95% CI, 1.1–1.7), hypertension: HR, 1.4 ( P =0.003; 95% CI, 1.1–1.7), peripheral vascular disease: HR, 1.6 ( P =0.001; 95% CI, 1.3–2.1), renal failure: HR, 1.7 ( P =0.012; 95% CI, 1.1–2.5), statins: HR, 0.8 ( P =0.049; 95% CI, 0.7–1.0), clopidogrel: HR, 0.6 ( P =0.032; 95% CI, 0.4–1.0). Conclusions— The increase in stroke with age after CABG is moderate and the relation uncertain in ages older than 70 years. Declining CABG in elderly patients because of risk of stroke purely on the basis of high age is debatable.