Gender differences in stroke risk among the elderly after coronary artery surgery

Previous studies have shown that women are at higher risk than men for stroke after coronary artery bypass graft (CABG) surgery, but gender differences in systemic atherosclerosis have not been studied adequately. We investigated gender differences in the incidence of craniocervical and ascending aortic atherosclerosis and other risk factors for stroke in elderly patients (age > or =60 yr) undergoing CABG surgery.

Data were prospectively collected on 720 patients (31.8% women) undergoing CABG surgery. All patients underwent preoperative brain magnetic resonance imaging and angiography to assess for prior cerebral infarctions, carotid artery stenosis, and intracranial arterial stenosis. Epiaortic ultrasound was performed at the time of surgery to assess for atherosclerosis of the ascending aorta. Cognitive status was measured using the Hasegawa-dementia score in all patients before surgery and on the seventh postoperative day.

Women were older and had more hypertension and intracranial arterial stenosis than did men. Men had significantly higher rates of hyperlipidemia, peripheral vascular disease, abdominal aortic aneurysm, smoking history, severe carotid artery stenosis, and severe aortic atherosclerosis than did women. Although there were no differences in prior cerebral infarction or preoperative cognitive impairment, the rate of perioperative stroke was marginally higher in men than in women (3.9% vs 1.3%, P = 0.066). Univariate predictors of perioperative stroke were prior cerebral infarctions, ascending aortic atherosclerosis, preexisting cognitive impairment, and peripheral vascular disease. Stepwise logistic regression analysis demonstrated that significant independent predictors of perioperative stroke were prior cerebral infarctions and aortic atherosclerosis.

These data suggest that men are more likely than women to have risk factors for stroke, including severe carotid artery stenosis, severe aortic atherosclerosis, and peripheral vascular disease. The rates of prior cerebral infarction and preoperative cognitive impairment were similar between genders.