First-Ever Ischemic Stroke and Incident Major Adverse Cardiovascular Events in 93 627 Older Women and Men

Abstract

Background and Purpose— Stroke risk is sex-specific, but little is known about sex differences of poststroke major adverse cardiovascular events (MACEs). Stroke-related brain damage causes autonomic dysfunction and inflammation, sometimes resulting in cardiac complications. Sex-specific cardiovascular susceptibility to stroke without the confounding effect of preexisting heart disease constitutes an unexplored field because previous studies focusing on sex differences in poststroke MACE have not excluded patients with known cardiovascular comorbidities. We therefore investigated sex-specific risks of incident MACE in a heart disease-free population-based cohort of patients with first-ever ischemic stroke and propensity-matched individuals without stroke. Methods— We included Ontario residents ≥66 years, without known cardiovascular comorbidities, with first-ever ischemic stroke between 2002 and 2012 and propensity-matched individuals without stroke. We investigated the 1-year risk of incident MACE (acute coronary syndrome, myocardial infarction, incident coronary artery disease, coronary revascularization procedures, incident heart failure, or cardiovascular death) separately for females and males. For estimating cause-specific adjusted hazard ratios, we adjusted Cox models for variables with weighted standardized differences >0.10 or those known to influence MACE risk. Results— We included 93 627 subjects without known cardiovascular comorbidities; 21 931 with first-ever ischemic stroke and 71 696 propensity-matched subjects without stroke. Groups were well-balanced on propensity-matching variables. There were 53 476 women (12 421 with and 41 055 without ischemic stroke) and 40 151 men (9510 with and 30 641 without ischemic stroke). First-ever ischemic stroke was associated with increased risk of incident MACE in both sexes. The risk was time-dependent, highest within 30 days (women: adjusted hazard ratio, 25.1 [95% CI, 19.3–32.6]; men: aHR, 23.4 [95% CI, 17.2–31.9]) and decreasing but remaining significant between 31 and 90 days (women: aHR, 4.8 [95% CI, 3.8–6.0]; men: aHR, 4.2 [95% CI, 3.3–5.4]), and 91 to 365 days (aHR, 2.1 [95% CI, 1.8–2.3]; men: aHR, 2.0 [95% CI, 1.7–2.3]). Conclusions— In this large population-based study, ischemic stroke was independently associated with increased risk of incident MACE in both sexes.