Implication of Earlier Carotid Atherosclerosis for Stroke and Its Subtypes

Yoji Nagai, MD, PhD, Kazuo Kitagawa, MD, PhD, Masayasu Matsumoto, MD, PhD


Prev Cardiol. 2003;6(2) 

In This Article

Carotid Atherosclerosis as a Risk Factor for Stroke

Because advanced carotid stenosis often impairs cerebral blood flow and becomes the nest for emboli, it is a well-defined risk factor for stroke. In this regard, ultrasound studies have shown that carotid stenosis ≥70% increases the incidence of future stroke, whereas the risk is limited when the stenosis is ≤60%.[28] Earlier, less severe carotid atherosclerosis has also been linked to the risk for future stroke.[3,4,29] In the Rotterdam Study,[3] each 1 SD change in CCA IMT increased the risk for stroke by 34% in asymptomatic volunteers over 2.7 years, independent of traditional cardiovascular risk factors. The Cardiovascular Health Study[4] showed that each 1 SD change in IMT was independently associated with an increase in the yearly incidence of stroke by 28% in asymptomatic volunteers. Moreover, the presence of carotid plaques had an association with transient ischemic attack (TIA),[30] and enlargement of these lesions increased the risk for future neurologic events.[31] Additionally, carotid PS was higher in patients with ischemic cerebrovascular diseases,[32] and was predictive of future stroke in a population at higher cardiovascular risk.[33] Taken together, even in the absence of advanced stenosis carotid atherosclerosis is likely to be associated with the risk for stroke.