Birns Jonathan, Morris Robin, Jarosz Jozef, Markus Hugh, Kalra Lalit
Department of Stroke Medicine, Academic Neurosciences Centre, Institute of Psychiatry, King's College London, Camberwell, UK.
J Hypertens. 2009 May;27(5):1042-8. doi: 10.1097/HJH.0b013e32832810d5.
Although hypertension is known to cause brain damage and cognitive impairment, epidemiological studies suggest that lower blood pressure (BP) in patients with established cerebrovascular disease is associated with more rapid cognitive decline. We investigated the relationship between 24-h ambulatory blood pressure (ABP) measurements, cerebrovascular disease load and cognitive performance in patients with hypertensive cerebrovascular disease.
Eighty-eight patients (mean age 65+9 years) with hypertensive cerebrovascular disease on MRI were recruited. BP was controlled optimally. ABP monitoring, quantitative MRI analysis of white matter lesion (WML) volume and executive cognitive function tests were performed. The relationships between ABP variables, WML volume and executive test performance were examined using regression analyses to adjust for age, sex, vascular risk profile and premorbid intelligence.
Patients had a mean daytime ABP of 96+10 mmHg and mean night-time ABP of 88+11 mmHg (P = 0.001). Median WML volume was 8464 mm3. There were no significant associations between ABP variables and supratentorial WML volumes. Infratentorial WML volume correlated negatively with night-time mean BP (r = -0.6, P = 0.002) and positively with nocturnal dipping (r = 0.6, P = 0.002). Higher night-time mean BP was an independent predictor of reduced infratentorial WML volume (R2: 0.460, P = 0.008).Infratentorial WML volume correlated with impairments of phonemic verbal fluency (r = 0.5, P < 0.001) and choice reaction time (r = 0.7, P < 0.005).
Physiological falls in nocturnal BP may be associated with increased infratentorial WML volume and cognitive dysfunction in optimally controlled hypertensive patients with cerebrovascular disease.
尽管已知高血压会导致脑损伤和认知障碍，但流行病学研究表明，已患脑血管疾病患者的血压降低与认知功能衰退加快有关。我们调查了高血压性脑血管疾病患者24小时动态血压（ABP）测量值、脑血管疾病负荷与认知表现之间的关系。
招募了88例经MRI检查确诊为高血压性脑血管疾病的患者（平均年龄65±9岁）。血压得到最佳控制。进行了ABP监测、对白质病变（WML）体积的定量MRI分析以及执行认知功能测试。使用回归分析来检验ABP变量、WML体积与执行测试表现之间的关系，以调整年龄、性别、血管风险状况和病前智力。
患者白天平均ABP为96±10 mmHg，夜间平均ABP为88±11 mmHg（P = 0.001）。WML体积中位数为8464 mm³。ABP变量与幕上WML体积之间无显著关联。幕下WML体积与夜间平均血压呈负相关（r = -0.6，P = 0.002），与夜间血压下降呈正相关（r = 0.6，P = 0.002）。较高的夜间平均血压是幕下WML体积减小的独立预测因素（R²：0.460，P = 0.008）。幕下WML体积与音素言语流畅性受损（r = 0.5，P < 0.001）和选择反应时间（r = 0.7，P < 0.005）相关。
在血压得到最佳控制的高血压性脑血管疾病患者中，夜间血压的生理性下降可能与幕下WML体积增加和认知功能障碍有关。
