Am Fam Physician. 1998;58(1):219-220
Although auscultation for carotid bruits is easily performed and noninvasive, its utility for identifying asymptomatic elderly patients at high risk for stroke is not known. Shorr and colleagues retrospectively studied the association between asymptomatic carotid bruits and stroke in elderly patients with isolated systolic hypertension.
The study group consisted of 4,442 participants in the Systolic Hypertension in the Elderly Program who were followed for an average of 4.5 years. Patients were excluded if they had a history of stroke with resultant paresis, transient ischemic attack plus carotid bruit, two transient ischemic attacks in the same distribution, atrial fibrillation or flutter, or if they took insulin, lived in a nursing home or were diagnosed with dementia. The presence of carotid bruits was noted on the physical examination. Medical records were reviewed to determine whether patients developed symptoms of transient ischemic attack or stroke. If these symptoms were present, type and location were noted.
Carotid bruits were found in 284 patients and were more common in older and non-white patients. Patients with bruits tended to have a higher systolic blood pressure and were more likely to be smokers. A total of 231 strokes were identified in 18,488 person-years of follow-up. Twenty-one strokes occurred in the 1,129 person-years of follow-up in patients with carotid bruits. This event rate was 1.86 per 100 person-years, compared with 1.21 for those without bruits. Those with unilateral bruits had an event rate of 2.21, compared with a rate of 1.40 per 100 person-years for those with bilateral bruits. For patients aged 60 to 69 years, there was a trend toward increased stroke risk. However, for patients aged 70 years and older, the presence of carotid bruits was not related to the risk of subsequent stroke.
The authors conclude that carotid bruit is not a useful clinical marker of increased stroke risk. Bruits are, however, a sign of generalized atherosclerosis. Therefore, high-risk management strategies should not be undertaken in elderly patients with isolated systolic hypertension who have asymptomatic bruits.
In an accompanying editorial, Aronson and Landefeld concur that carotid auscultation cannot be recommended in patients who are asymptomatic. Instead, efforts should be made to identify and treat known risk factors for stroke. Such treatment should include anticoagulation in patients with atrial fibrillation, blood pressure control in patients with hypertension and cholesterol lowering with statins in patients with coronary artery disease.