Mackinnon Andrew D, Jerrard-Dunne Paula, Sitzer Matthias, Buehler Alexandra, von Kegler Stefan, Markus Hugh S
Department of Clinical Neurosciences, St. George's Hospital Medical School, Cranmer Terrace, Tooting, London, United Kingdom.
Stroke. 2004 Sep;35(9):2150-4. doi: 10.1161/01.STR.0000136720.21095.f3. Epub 2004 Jul 8.
Carotid intima-media thickness (IMT) progression rates are increasingly used as an intermediate outcome for vascular risk. The carotid bifurcation (BIF) and internal carotid artery (ICA) are predilection sites for atherosclerosis. IMT measures from these sites may be a better estimate of atherosclerosis than common carotid artery (CCA) IMT. The study aim was to evaluate site-specific IMT progression rates and their relationships to vascular risk factors compared with baseline IMT measurements.
In a community population (n=3383), ICA-IMT, BIF-IMT, CCA-IMT, and vascular risk factors were evaluated at baseline and at 3-year follow-up.
Mean (SD) IMT progression was significantly greater at the ICA (0.032 [0.109] mm/year) compared with the BIF (0.023 [0.108] mm/year) and the CCA (0.001 [0.040] mm/year) (P<0.001). Only ICA-IMT progression significantly correlated with baseline vascular risk factors (age, male gender, hypertension, diabetes, and smoking). Change in risk factor profile over follow-up, estimated using the Framingham risk score, was a predictor of IMT progression only. For all arterial sites, correlations were stronger, by a factor of 2 to 3, for associations with baseline IMT compared with IMT progression.
Progression rates at the ICA rather than the CCA yield greater absolute changes in IMT and better correlations with vascular risk factors. Vascular risk factors correlate more strongly with baseline IMT than with IMT progression. Prospective data on IMT progression and incident vascular events are required to establish the true value of progression data as a surrogate measure of vascular risk.
颈动脉内膜中层厚度（IMT）进展率越来越多地被用作血管风险的中间结局指标。颈动脉分叉处（BIF）和颈内动脉（ICA）是动脉粥样硬化的好发部位。这些部位的IMT测量值可能比颈总动脉（CCA）的IMT更能准确评估动脉粥样硬化情况。本研究旨在评估特定部位的IMT进展率及其与血管危险因素的关系，并与基线IMT测量值进行比较。
在一个社区人群（n = 3383）中，在基线和3年随访时评估ICA-IMT、BIF-IMT、CCA-IMT及血管危险因素。
与BIF（0.023 [0.108] mm/年）和CCA（0.001 [0.040] mm/年）相比，ICA处的平均（标准差）IMT进展显著更大（0.032 [0.109] mm/年）（P<0.001）。只有ICA-IMT进展与基线血管危险因素（年龄、男性、高血压、糖尿病和吸烟）显著相关。使用弗雷明汉风险评分估计的随访期间危险因素谱变化仅是IMT进展的一个预测因素。对于所有动脉部位，与基线IMT的相关性比与IMT进展的相关性强2至3倍。
ICA处而非CCA处的进展率导致IMT的绝对变化更大，且与血管危险因素的相关性更好。血管危险因素与基线IMT的相关性比与IMT进展的相关性更强。需要关于IMT进展和血管事件发生的前瞻性数据，以确定进展数据作为血管风险替代指标的真正价值。
