Risk of myocardial infarction or vascular death after first ischemic stroke: the Northern Manhattan Study

Abstract

Background and purpose: In national guidelines, absolute long-term risk of myocardial infarction (MI) or coronary death determines target low-density lipoprotein levels, but stroke patients are not explicitly addressed. We determined the absolute 5-year risk of cardiovascular outcomes and their predictors after first ischemic stroke in a multiethnic cohort.

Methods: A population-based cohort of first ischemic stroke patients > or =40 years old was prospectively followed annually for recurrent stroke, MI and cause-specific mortality. Kaplan-Meier 5-year risks for MI or vascular death (primary outcome), and other cardiovascular events, were calculated. Univariate and multivariate Cox proportional hazards models were used to calculate hazard ratios and 95% CI for predictors of cardiovascular outcomes.

Results: Mean age (n=655) was 69.7+/-12.7 years; 55.4% of participants were women, and 51.3% Hispanic. The 5-year risk of MI or vascular death was 17.4% (95% CI, 14.2% to 20.6%). Independent historical predictors of MI or vascular death were age >70 years (hazard ratio 1.62, 1.07 to 2.44), history of coronary artery disease (hazard ratio 1.76, 1.13 to 2.74), and atrial fibrillation (hazard ratio 1.76, 1.05 to 2.94). In the lowest risk group, those < or =70 years old without coronary artery disease, 5-year risk of MI or vascular death was 9.7%.

Conclusions: The absolute risk of MI or vascular death after ischemic stroke, even in those without high-risk features, approximates levels used by national organizations to designate groups of patients at high risk of vascular events. The comparability of levels of absolute risk among stroke and cardiac patients may have treatment implications.