Carotid Plaques Increase the Risk of Stroke and Subtypes of Cerebral Infarction in Asymptomatic Elderly

Abstract

Background-Few studies have quantified the relation between carotid plaques and stroke in asymptomatic patients, and limited data exist on the importance of location of plaques or the association with subtypes of cerebral infarction. We investigated the relationship between carotid plaques, measured at different locations, and risk of stroke and subtypes of cerebral infarction in a population-based study. Methods and Results-The study was based on the Rotterdam Study and included 4217 neurologically asymptomatic subjects aged 55 years or older. Presence of carotid plaques at 6 locations in the carotid arteries was assessed at baseline. Severity was categorized according to the number of affected sites. After a mean follow-up of 5.2 years, 160 strokes had occurred. Data were analyzed using Cox proportional hazards regression. Plaques increased the risk of stroke and cerebral infarction Ϸ1.5-fold, irrespective of plaque location. Severe carotid plaques increased the risk of nonlacunar infarction in anterior (RR 3.2 [95% CI, 1.1 to 9.7]) but not in posterior circulation (RR 0.6 [95% CI, 0.1 to 4.9]). A Ͼ10-fold increased risk of lacunar infarction was found in subjects with severe plaques (RR 10.8 [95% CI, 1.7 to 69.7]). No clear difference in risk estimates was seen between ipsilateral and contralateral infarction. Conclusions-Carotid plaques increase the risk of stroke and cerebral infarction, irrespective of their location. Plaques increase the risk of infarctions in the anterior but not in the posterior circulation. It is likely that carotid plaques in neurologically asymptomatic subjects are both markers of generalized atherosclerosis and sources of thromboemboli.

Prevalence of Carotid Plaque in a 63‐ to 65‐Year‐Old Norwegian Cohort From the General Population: The ACE (Akershus Cardiac Examination) 1950 Study

“…This is supported by a low rate of current smoking, a mean SCORE risk of 3.6%, and a high proportion of diagnosed and treated hypertension at study inclusion. Furthermore, the low prevalence of high‐grade stenosis in our study corresponds with previous studies,4, 15, 16, 27 suggesting a similar rather than a greater atherosclerotic burden. Despite this, our results showed the presence of plaque in 9 of 10 participants.…”

“…Carotid plaque, however, compared with cIMT, has significantly higher prognostic accuracy in predicting future cardiovascular events and is recommended for risk assessment 28, 30. Increased plaque score in high‐risk populations predicts coronary lesions,31 and presence of plaque increases the risk of stroke ≈1.5‐fold, independent of plaque location 4. The same study reported a dose‐dependent association between carotid plaques and stroke risk 4.…”

“…In the present study, the definition of plaque was in accordance with the Mannheim Carotid Intima–Media Thickness and Plaque Consensus from 2004,11 in which cIMT ≥1.5 mm was considered as a plaque, whereas earlier studies used other definitions. In addition, the studies have included either older4, 21 or younger patients,3, 5, 23 men only,21 or examination of only 1 artery 5…”

“…Previous reports regarding the prevalence of carotid plaque and cIMT thickness are scarce and of older date 3, 4, 5. New and improved ultrasound techniques enhance atherosclerosis detection and thus may influence the measured plaque prevalence.…”

Risk factors of carotid plaque and carotid common artery intima‐media thickening in a high‐stroke‐risk population

“…Another finding of the Rotterdam Study was a dose‐dependent relationship between the risk of stroke and carotid plaques. The participants with 3–4 plaques had 5‐fold increased risk, participants with 5–6 plaques had 10‐fold increased risk of lacunar infarction, regardless of their locations (Hollander et al., 2002). More risk factors and higher level of risk factors mean higher risk of diseases, so the high‐risk population mentioned above need to modify their risk factors more strictly to avoid the serious consequences of cerebrovascular or cardiovascular diseases.…”