Supplementary Material for: Age-Distinct Predictors of Symptomatic Cervicocephalic Atherosclerosis

<i>Background:</i> Little is known about whether vascular risk factors predispose to atherosclerotic stroke depending on age. We evaluated predictors of large vessel atherosclerotic stroke (LVAS) stratified by age in two geographically and racially distinct study populations. <i>Methods:</i> Data collected over a 4-year period in prospectively maintained registries on 3,053 subjects with ischemic cerebrovascular events were analyzed: 1,982 patients from a hospital in South Korea and 1,071 patients admitted to a hospital in Los Angeles, Calif., USA. Independent vascular risk factor associations with LVAS mechanism were evaluated in three groups stratified by age (years) at symptom onset: young (≤50 years), older (51–75 years), and oldest (&gt;75 years). <i>Results:</i> Altogether at both study sites, 972 (31.8%) patients had LVAS mechanism, of whom 391 (40.2%) were female. Risk factor profiles were not significantly different between LVAS versus other stroke mechanisms. Among young patients, after adjusting for covariates, current smoking was the only predictor of atherosclerotic stroke at both Korean (OR 2.04; 95% CI: 1.13–3.69) and Californian sites (OR 4.78, 95% CI 1.54–14.89), while the metabolic syndrome was the only predictor of atherosclerotic stroke among the older patients (OR 1.58, 95% CI 1.17–2.12 for Korean; OR 1.75, 95% CI 1.07–2.84 for Californian), but not in the young or oldest groups. <i>Conclusions:</i> Across race and region, the estimated impact of vascular risk factors for LVAS varies by age, and this is most prominently seen among persons of less than 76 years of age. Some risk factors have an early effect (smoking) and others an effect that plays out over time.

背景：目前关于血管危险因素是否会依年龄不同而诱发动脉粥样硬化性卒中的相关研究尚少。本研究在两个地理与种族特征均存在差异的研究队列中，针对按年龄分层的大血管动脉粥样硬化性卒中（large vessel atherosclerotic stroke, LVAS）预测因素展开了评估。方法：本研究对两项前瞻性维护的登记系统中、历时4年收集的3053例缺血性脑血管事件受试者数据进行了分析：其中1982例来自韩国某医院，1071例来自美国加利福尼亚州洛杉矶市某医院的住院患者。按症状发作时的年龄将受试者分为三组：青年组（≤50岁）、中老年组（51~75岁）及高龄组（＞75岁），随后分别评估各血管危险因素与LVAS发病机制的独立关联。结果：两项研究的全部受试者中，共972例（31.8%）符合LVAS发病机制，其中女性391例（40.2%）。LVAS组与其他卒中类型组的危险因素谱无显著差异。在青年组受试者中，校正混杂因素后，当前吸烟是韩、美两地受试者LVAS的唯一预测因素（韩国队列：比值比（OR）2.04，95%置信区间（CI）1.13~3.69；加利福尼亚队列：OR 4.78，95% CI 1.54~14.89）；而在中老年组中，代谢综合征是LVAS的唯一预测因素（韩国队列：OR 1.58，95% CI 1.17~2.12；加利福尼亚队列：OR 1.75，95% CI 1.07~2.84），但该关联未在青年组或高龄组中观察到。结论：无论种族与地域差异，血管危险因素对LVAS的影响程度均随年龄而异，该差异在76岁以下人群中最为显著。部分危险因素（如吸烟）仅在疾病早期发挥作用，其余危险因素的影响则随病程逐渐显现。