Supplementary Material for: Vascular White Matter Lesions in Young Adults: A Neurology Outpatient Clinic Registry

<b><i>Introduction:</i></b> Although frequently assumed to be age-related changes, vascular white matter lesions (WML) are sometimes found in young adults. Etiology is usually attributed to sporadic small vessel disease; nevertheless, genetic disorders may also be implicated. We aimed to characterize the population of young adults with vascular WML in Neurology outpatient clinics. <b><i>Methods:</i></b> Neurologists from 12 Portuguese hospitals were invited to include patients aged 18–55 years evaluated in consultation, with vascular WML on MRI, scoring II or III in the Fazekas scale. Central imaging validation was performed by 2 independent, blinded, Neuroradiologists. Demographic and clinical data were collected as well as results of investigations performed. <b><i>Results:</i></b> During 2 years, 77 patients were included (mean age 47.7 years). Vascular risk factors were present in 88.3% patients (hypertension in 53.2%) and previous history of stroke in 36.4%. Patients without history of stroke were younger (46.6 ± 7.2 vs. 49.6 ± 3.9 years, <i>p</i> = 0.045) and had fewer vascular risk factors (<i>p</i> &lt; 0.001). They were more frequently females (87.8 vs. 46.4%, <i>p</i> &lt; 0.001), and headache (30.6 vs. 3.6%, <i>p</i> = 0.007), contrary to focal symptoms (16.3 vs. 53.6%, <i>p</i> = 0.001), was the most frequent reason of referral. Etiological investigations performed differed between Neurologists. A genetic disorder was identified in 6 out of 58 patients (CADASIL <i>n</i> = 5; COL4A1 <i>n</i> = 1). <b><i>Conclusion:</i></b> Young adults with vascular WML evaluated in Neurology outpatient clinics concentrate in the oldest age groups. Vascular risk factors should be screened carefully in this population. Among patients without history of stroke, females largely outweigh males. Diagnostic investigations performed do not follow a standardized protocol.

<b><i>引言：</i></b> 尽管血管性脑白质病变（vascular white matter lesions, WML）常被认为是与年龄相关的病理改变，但该病变有时也会在青年人群中被检出。其病因通常以散发性小血管病为主；不过，遗传紊乱也可能参与发病。本研究旨在明确神经内科门诊中伴血管性WML的青年人群特征。<b><i>方法：</i></b> 邀请来自葡萄牙12家医院的神经内科医师纳入经门诊评估的18~55岁患者，这些患者的磁共振成像（Magnetic Resonance Imaging, MRI）检查显示存在血管性WML，且Fazekas量表（Fazekas scale）评分达Ⅱ级或Ⅲ级。由2名独立且采用盲法的神经放射学医师完成中枢影像学复核。研究收集了受试者的人口统计学与临床资料，以及各项检查的检测结果。<b><i>结果：</i></b> 研究周期为2年，共纳入77例患者（平均年龄47.7岁）。其中88.3%的患者存在血管性危险因素（53.2%合并高血压），36.4%有卒中既往史。无卒中既往史的患者年龄更小（46.6±7.2岁 vs 49.6±3.9岁，*p*=0.045），血管性危险因素数量更少（*p*<0.001）；该群体女性占比更高（87.8% vs 46.4%，*p*<0.001），头痛（30.6% vs 3.6%，*p*=0.007）为最常见的就诊诱因，而局灶性症状（16.3% vs 53.6%，*p*=0.001）则与之相反。不同神经内科医师采用的病因学检查方案存在差异。58例患者中检出6例存在遗传紊乱（伴皮质下梗死及白质脑病的常染色体显性遗传性脑动脉病（CADASIL）5例；COL4A1基因突变1例）。<b><i>结论：</i></b> 神经内科门诊就诊的伴血管性WML青年人群多集中于较高年龄组。应对该人群进行细致的血管性危险因素筛查。在无卒中既往史的患者中，女性占比显著高于男性。当前采用的诊断性检查未遵循标准化流程。