Wolfson Centre for Prevention of Stroke and Dementia, Nuffield Department of Clinical Neurosciences, University of Oxford, John Radcliffe Hospital, Headley Way, Oxford OX3 9DU, UK.
Eur Heart J. 2021 Feb 14;42(7):750-757. doi: 10.1093/eurheartj/ehaa756.
White matter hyperintensities (WMH) progress with age and hypertension, but the key period of exposure to elevated blood pressure (BP), and the relative role of systolic BP (SBP) vs. diastolic BP (DBP), remains unclear. This study aims to determine the relationship between WMH and concurrent vs. past BP.
UK Biobank is a prospective community-based cohort of 40-69-year olds from 22 centres, with magnetic resonance imaging in a subgroup of over 40 000 people at 4-12 years after baseline assessment. Standardized associations between WMH load (WMH volume normalized by total white matter volume and logit-transformed) and concurrent vs. past BP were determined using linear models, adjusted for age, sex, cardiovascular risk factors, BP source, assessment centre, and time since baseline. Associations adjusted for regression dilution bias were determined between median WMH and usual SBP or DBP, stratified by age and baseline BP.In 37 041 eligible participants with WMH data and BP measures, WMH were more strongly associated with concurrent SBP [DBP: β = 0.064, 95% confidence interval (CI) 0.050-0.078; SBP: β = 0.076, 95% CI 0.062-0.090], but the strongest association was for past DBP (DBP: β = 0.087, 95% CI 0.064-0.109; SBP: β = 0.045, 95% CI 0.022-0.069), particularly under the age of 50 (DBP: β = 0.103, 95% CI 0.055-0.152; SBP: β = 0.012, 95% CI -0.044 to 0.069). Due to the higher prevalence of elevated SBP, median WMH increased 1.126 (95% CI 1.107-1.146) per 10 mmHg usual SBP and 1.106 (95% CI 1.090-1.122) per 5 mmHg usual DBP, whilst the population attributable fraction of WMH in the top decile was greater for elevated SBP (19.1% for concurrent SBP; 24.4% for past SBP). Any increase in BP, even below 140 for SBP and below 90 mmHg for DBP, and especially if requiring antihypertensive medication, was associated with increased WMH.
WMH were strongly associated with concurrent and past elevated BP with the population burden of severe WMH greatest for SBP. However, before the age of 50, DBP was more strongly associated with WMH. Long-term prevention of WMH may require control of even mildly elevated midlife DBP.
脑白质高信号（WMH）随年龄和高血压而进展，但暴露于高血压的关键时期以及收缩压（SBP）与舒张压（DBP）的相对作用仍不清楚。本研究旨在确定WMH 与同期和既往血压之间的关系。
英国生物银行（UK Biobank）是一个由 22 个中心的 40-69 岁人群组成的前瞻性社区队列，在基线评估后 4-12 年内对超过 40000 人的亚组进行磁共振成像。使用线性模型确定 WMH 负荷（WMH 体积与总白质体积的比值和对数转换）与同期和既往 BP 之间的标准化关联，并调整年龄、性别、心血管危险因素、BP 来源、评估中心和基线后时间。根据年龄和基线 BP 对中位 WMH 和常用 SBP 或 DBP 进行分层，确定 SBP 或 DBP 中位数与回归稀释偏倚之间的关联。在 37041 名有 WMH 数据和 BP 测量值的合格参与者中，WMH 与同期 SBP 的相关性更强[DBP：β=0.064，95%置信区间（CI）0.050-0.078；SBP：β=0.076，95%CI 0.062-0.090]，但最强的相关性是过去的 DBP（DBP：β=0.087，95%CI 0.064-0.109；SBP：β=0.045，95%CI 0.022-0.069），特别是年龄在 50 岁以下（DBP：β=0.103，95%CI 0.055-0.152；SBP：β=0.012，95%CI-0.044 至 0.069）。由于 SBP 升高的患病率较高，中位 WMH 每增加 10mmHg 常用 SBP 增加 1.126（95%CI 1.107-1.146），每增加 5mmHg 常用 DBP 增加 1.106（95%CI 1.090-1.122），而 SBP 最高十分位数的 WMH 人群归因分数更高（同期 SBP 为 19.1%；过去 SBP 为 24.4%）。即使 SBP 低于 140mmHg，DBP 低于 90mmHg，且尤其需要抗高血压药物治疗，BP 的任何升高都与 WMH 增加有关。
WMH 与同期和既往升高的 BP 密切相关，严重 WMH 的人群负担最大的是 SBP。然而，在 50 岁之前，DBP 与 WMH 的相关性更强。WMH 的长期预防可能需要控制中年时期甚至轻微升高的 DBP。
