Department of Neurology, Johann Wolfgang Goethe-University, Schleusenweg 2-16, Frankfurt am Main D-60528, Germany.
Eur Heart J. 2010 Aug;31(16):2041-8. doi: 10.1093/eurheartj/ehq189. Epub 2010 Jun 8.
Carotid intima media thickness (cIMT) is an intermediate phenotype of early atherosclerosis that independently predicts vascular events. It is often suggested that cIMT be used as a screening tool to select subjects with an elevated event risk. Whether cIMT adds information to traditional risk models has so far received little investigation.
The 10-year follow-up of 4904 subjects from the Carotid Atherosclerosis Progression Study (CAPS) without pre-existing vascular disease included cardiovascular events and total mortality. Using Cox models and reclassification statistics, we investigated the usefulness of cIMT in individual risk prediction beyond the Framingham and the SCORE models, using risk strata of 0-5, 5-10, 10-20, and >or=20% over 10 years. Carotid intima media thickness was significantly and independently predictive for cardiovascular events. Compared with a model using the Framingham risk factors, a second model that included the common carotid-IMT led to the reclassification of 357 subjects (8.1%). In 107 subjects (30.0%), this reclassification was correct as confirmed with the actual outcome over 10 years. Net reclassification improvement was -1.41% (P = NS); integrated discrimination improvement was 0.04% (P = NS). More subjects were shifted to lower than to higher risk categories by the inclusion of cIMT. Analyses including other endpoint definitions, other carotid segments, and the SCORE risk model for baseline prediction did not result in consistently better risk prediction with cIMT.
Despite cIMT being predictive for cardiovascular endpoints, it did not consistently improve the risk classification of individuals. Carotid intima media thickness may not be useful for the risk stratification of individuals in the general population.
颈动脉内膜中层厚度（cIMT）是早期动脉粥样硬化的中间表型，可独立预测血管事件。人们常建议将 cIMT 用作筛选工具，以选择具有较高事件风险的受试者。cIMT 是否为传统风险模型提供了更多信息，目前研究甚少。
无先前血管疾病的颈动脉粥样硬化进展研究（CAPS）4904 例受试者的 10 年随访包括心血管事件和全因死亡率。使用 Cox 模型和再分类统计，我们研究了 cIMT 在Framingham 和 SCORE 模型之外的个体风险预测中的作用，使用了 10 年内风险分层为 0-5%、5-10%、10-20%和≥20%。颈动脉内膜中层厚度与心血管事件显著独立相关。与使用Framingham 危险因素的模型相比，包含颈总动脉-IMT 的第二个模型使 357 例受试者（8.1%）的分类发生改变。在 107 例受试者（30.0%）中，这种再分类是正确的，因为在 10 年内证实了实际结果。净再分类改善为-1.41%（P=NS）；综合判别改善为 0.04%（P=NS）。纳入 cIMT 后，更多的受试者被转移到较低的风险类别。包括其他终点定义、其他颈动脉节段和 SCORE 风险模型的基线预测的分析并未导致 cIMT 一致地改善个体风险预测。
尽管 cIMT 对心血管终点有预测作用，但并未一致改善个体的风险分类。cIMT 可能不适用于一般人群中个体的风险分层。
