Long-Term Risk of Myocardial Infarction Compared to Recurrent Stroke After Transient Ischemic Attack and Ischemic Stroke: Systematic Review and Meta-Analysis

BackgroundUncertainties remain about the current risk of myocardial infarction (MI) after ischemic stroke or transient ischemic attack. Methods and ResultsWe undertook a systematic review to estimate the long-term risk of MI, compared to recurrent stroke, with temporal trends in ischemic stroke/transient ischemic attack patients. Annual risks and 95% confidence intervals (95% CI) of MI and recurrent stroke were estimated using random-effect meta-analyses. We calculated incidence ratios of MI/recurrent stroke, for fatal and nonfatal events, using similar analyses. Rate ratios for MI in patients with potential risk factors compared to those without were calculated using Poisson regression. A total of 58 studies (131299 patients) with a mean (range) follow-up of 3.5 (1.0-10.0) years were included. The risk of MI was 1.67%/y (95% CI 1.36-1.98, P-het<0.001 for heterogeneity) and decreased over time (P-int=0.021); 96% of the heterogeneity between studies was explained by study design, study period, follow-up duration, mean age, proportion of patients on antithrombotic therapy, and incident versus combined ischemic stroke/transient ischemic attack. The risk of recurrent stroke was 4.26%/y (95% CI 3.43-5.09, P-het<0.001), with no change over time (P-int=0.63). The risk of fatal MI was half the risk of recurrent strokes ending in fatality (incidence ratio=0.51, 95% CI 0.14-0.89, P-het=0.58). The risk of nonfatal MI was 75% smaller than the risk of recurrent nonfatal stroke (incidence ratio=0.25, 95%CI 0.02-0.50, P-het=0.68). Male sex, hypertension, coronary and peripheral artery diseases were associated with a doubled risk of MI. ConclusionsAfter ischemic stroke/transient ischemic attack, the risk of MI is currently <2%/y, and recurrent stroke is a more common cause of death than MI.