Department of Gerontology and Geriatrics, Leiden University Medical Center, PO Box 9600, 2300 RC Leiden, Netherlands.
BMJ. 2013 Jul 29;347:f4600. doi: 10.1136/bmj.f4600.
To investigate the association between visit-to-visit variability in blood pressure and cognitive function in old age (>70 years).
Prospective cohort study.
PROSPER (PROspective Study of Pravastatin in the Elderly at Risk) study, a collaboration between centres in Ireland, Scotland, and the Netherlands.
5461 participants, mean age 75.3 years, who were at risk of cardiovascular disease. Blood pressure was measured every three months during an average of 3.2 years. Visit-to-visit variability in blood pressure was defined as the standard deviation of blood pressure measurements between visits.
Four domains of cognitive function, testing selective attention, processing speed, and immediate and delayed memory. In a magnetic resonance imaging substudy of 553 participants, structural brain volumes, cerebral microbleeds, infarcts, and white matter hyperintensities were measured.
Participants with higher visit-to-visit variability in systolic blood pressure had worse performance on all cognitive tests: attention (mean difference high versus low thirds) 3.08 seconds (95% confidence interval 0.85 to 5.31), processing speed -1.16 digits coded (95% confidence interval -1.69 to -0.63), immediate memory -0.27 pictures remembered (95% confidence interval -0.41 to -0.13), and delayed memory -0.30 pictures remembered (95% confidence interval -0.49 to -0.11). Furthermore, higher variability in both systolic and diastolic blood pressure was associated with lower hippocampal volume and cortical infarcts, and higher variability in diastolic blood pressure was associated with cerebral microbleeds (all P<0.05). All associations were adjusted for average blood pressure and cardiovascular risk factors.
Higher visit-to-visit variability in blood pressure independent of average blood pressure was associated with impaired cognitive function in old age.
探讨老年（>70 岁）人群血压变异性与认知功能的关系。
前瞻性队列研究。
PROSPER（高危老年人普伐他汀前瞻性研究）研究，该研究是爱尔兰、苏格兰和荷兰中心之间的合作。
5461 名参与者，平均年龄 75.3 岁，有心血管疾病风险。在平均 3.2 年的时间内，每三个月测量一次血压。血压变异性定义为两次就诊之间血压测量值的标准差。
认知功能的四个领域，测试选择性注意、处理速度以及即时和延迟记忆。在 553 名参与者的磁共振成像子研究中，测量了结构脑体积、脑微出血、梗死和脑白质高信号。
收缩压变异性较高的参与者在所有认知测试中表现更差：注意力（高与低三分位差异）3.08 秒（95%置信区间 0.85 至 5.31），处理速度 -1.16 位编码（95%置信区间-1.69 至-0.63），即时记忆 -0.27 张图片记住（95%置信区间-0.41 至-0.13），延迟记忆 -0.30 张图片记住（95%置信区间-0.49 至-0.11）。此外，收缩压和舒张压变异性较高与海马体积较小和皮质梗死有关，舒张压变异性较高与脑微出血有关（均 P<0.05）。所有关联均在平均血压和心血管危险因素调整后进行。
独立于平均血压的血压变异性较高与老年时认知功能受损有关。
