DeCarli C, Miller B L, Swan G E, Reed T, Wolf P A, Garner J, Jack L, Carmelli D
Department of Neurology, University of Kansas, Kansas City, USA.
Stroke. 1999 Mar;30(3):529-36. doi: 10.1161/01.str.30.3.529.
Cross-sectional studies show that cerebrovascular risk factors are associated with increased brain atrophy, accumulation of abnormal cerebral white matter signals, and clinically silent stroke. We extend these findings by examining the relationship between midlife cerebrovascular risk factors and later-life differences in brain atrophy, amount of abnormal white matter, and stroke on MRI.
Subjects were the 414 surviving members of the prospective National Heart, Lung, and Blood Institute Twin Study, who have been examined on 4 separate occasions, spanning the 25 years between 1969-1973 and 1995-1997. Quantitative measures of brain volume, volume of abnormal white matter signal (WMHI), and volume of stroke, when present, were obtained from those participating in the fourth examination.
The mean+/-SD age of the subjects was 47.2+/-3.0 years at initial examination and 72. 5+/-2.9 years at final examination. Average blood pressure (BP) levels were normal, although 32% of the subjects had received or were currently taking antihypertensive medications. As a group, 31% had symptomatic cardiovascular disease, 11% had symptomatic cerebrovascular disease, and 8% had symptomatic peripheral vascular disease. Both systolic and diastolic BP levels at initial examination were inversely related to brain volume and positively related to WMHI volume. Multiple regression analysis identified BP-related measures and vascular risk factors as significant predictors of brain and WMHI volumes. In addition, the magnitude of orthostatic BP change was significantly associated with WMHI volume. Subjects with extensive amounts of WMHI had significantly higher systolic BP at the final examination and a higher prevalence of symptomatic cardiovascular and cerebrovascular disease, without significant differences in the prevalence of hypertension treatment.
Midlife BP measures are significantly associated with later-life brain and WMHI volumes and the prevalence of symptomatic vascular disease. Since WMHI share cerebrovascular risk factors and extensive WMHI are associated with symptomatic vascular disease, extensive WMHI may be a subclinical expression of cerebrovascular disease. Careful treatment of midlife BP elevations may diminish these later-life brain changes.
横断面研究表明，脑血管危险因素与脑萎缩增加、脑白质异常信号积聚及临床无症状性卒中相关。我们通过研究中年脑血管危险因素与晚年脑萎缩、脑白质异常量及MRI上卒中差异之间的关系，对这些发现进行了拓展。
研究对象为美国国立心肺血液研究所前瞻性双生子研究中414名存活成员，他们在1969年至1973年及1995年至1997年的25年间接受了4次独立检查。对参加第四次检查者的脑容量、脑白质异常信号体积（WMHI）及卒中体积（如有）进行了定量测量。
受试者初次检查时的平均年龄为47.2±3.0岁，末次检查时为72.5±2.9岁。尽管32%的受试者曾接受或正在服用抗高血压药物，但平均血压（BP）水平正常。总体而言，31%的受试者有症状性心血管疾病，11%有症状性脑血管疾病，8%有症状性外周血管疾病。初次检查时的收缩压和舒张压水平均与脑容量呈负相关，与WMHI体积呈正相关。多元回归分析确定与BP相关的指标和血管危险因素是脑和WMHI体积的重要预测因素。此外，直立性BP变化幅度与WMHI体积显著相关。WMHI广泛的受试者在末次检查时收缩压显著更高，有症状性心血管和脑血管疾病的患病率更高，高血压治疗患病率无显著差异。
中年BP测量值与晚年脑和WMHI体积及有症状性血管疾病的患病率显著相关。由于WMHI与脑血管危险因素相关，且广泛的WMHI与有症状性血管疾病相关，广泛的WMHI可能是脑血管疾病的亚临床表现。对中年BP升高进行仔细治疗可能会减少这些晚年脑变化。
