无症状性颈动脉狭窄的药物预防证据
最新的证据提示现有最好的药物治疗可能足以预防无症状性颈动脉狭窄患者卒中的发生。如果真是这样的，那么确定治疗所降低的风险就显得至关重要。为此，英国圣乔治大学卒中与痴呆研究中心的Alice King博士等人进行了一项研究，研究结果于近日在线发表在Stroke杂志上。结果发现：抗血小板治疗和血压控制是降低无症状颈动脉狭窄患者短期卒中和心血管风险的最重要因素。
该研究为无症状性颈动脉栓塞研究（ACES）前瞻性数据，用来确定现有治疗的效果和以后卒中或TIA的危险因素。研究人员对477位无症状性颈动脉狭窄的患者随访2年（每6个月随访1次）。每次随访危险因素的改变，并了解卒中预防止疗方案。使用时间依赖Cox回归确定现有治疗随着时间推移，与卒中、短暂性脑缺血发作和心血管死亡终点的相关性，以风险比和95%可信区间来表示。
研究结果显示：在多变量分析中，抗血小板药物(P=0.001)和较低的平均血压(P=0.002)是单侧卒中和短暂性脑缺血发作风险降低的独立预测因素。抗血小板药物(P<0.0001)和降压药(P<0.0001)是所有卒中和心血管死亡风险降低的独立预测因素。
该研究发现：抗血小板治疗和血压控制是降低无症状颈动脉狭窄患者短期卒中和心血管风险的最重要因素。目前用于无症状性颈动脉狭窄的药物（特别是他汀类），需要的更多的前瞻性数据进行验证。
The Effect of Medical Treatments on Stroke Risk in Asymptomatic Carotid Stenosis
Alice King, PhD, Martin Shipley, MSc, Hugh Markus, FRCP, for the ACES Investigators
Background and Purpose—Recent evidence suggests current best medical treatment may be sufficient to prevent stroke in patients with asymptomatic carotid stenosis. If this is the case, then it is important to determine risk reduction provided by treatments. Using Asymptomatic Carotid Emboli Study (ACES) prospective data, the effect of current treatment and risk factors on future stroke and transient ischemic attack risk were determined. Methods—Four-hundred seventy-seven patients with asymptomatic carotid stenosis were followed-up every 6 months for 2 years. Changes in risk factors and stroke prevention therapies were reviewed at each visit. Using time-dependent Cox regression, the relationship between current treatment over time was determined and presented as hazard ratios and 95% confidence intervals for risk of stroke, transient ischemic attack, and cardiovascular death end points. Results—On multivariate analysis, antiplatelets (P=0.001) and lower mean blood pressure (P=0.002) were independent predictors of reduced risk of ipsilateral stroke and transient ischemic attack. Antiplatelets (P<0.0001) and antihypertensives (P<0.0001) were independent predictors of a lower risk of any stroke or cardiovascular death. Conclusions—Antiplatelet therapy and blood pressure control are the most important factors in reducing short-term stroke and cardiovascular risk in patients with asymptomatic carotid stenosis. More prospective data are required for medical treatments in asymptomatic carotid stenosis in particular for current statin usage.
