O'Hare Celia, Kenny Rose-Anne, Aizenstein Howard, Boudreau Robert, Newman Anne, Launer Lenore, Satterfield Suzanne, Yaffe Kristine, Rosano Caterina
The Irish Longitudinal Study on Ageing (TILDA), Trinity College Dublin, Ireland.
Department of Psychiatry, University of Pittsburgh, PA, USA.
J Alzheimers Dis. 2017;57(4):1239-1250. doi: 10.3233/JAD-161228.
Associations between orthostatic blood pressure and cognitive status (CS) have been described with conflicting results.
We hypothesize that long-term exposure to lower orthostatic blood pressure is related to having worse CS later in life and that atrophy of regions involved in central regulation of autonomic function mediate these associations.
Three-to-four measures of orthostatic blood pressure were obtained from 1997-2003 in a longitudinal cohort of aging, and average systolic orthostatic blood pressure response (ASOBPR) was computed as % change in systolic blood pressure from sit-to-stand measured at one minute post stand. CS was determined in 2010-2012 by clinician-adjudication (n = 240; age = 87.1±2.6; 59% women; 37% black) with a subsample also undergoing concurrent structural neuroimaging (n = 129). Gray matter volume of regions related to autonomic function was measured. Multinomial regression was used to compare ASOBPR in those who were cognitively intact versus those with a diagnosis of mild cognitive impairment or dementia, controlling for demographics, trajectories of seated blood pressure, incident cardiovascular risk/events and medications measured from 1997 to 2012. Models were repeated in the subsample with neuroimaging, before and after adjustment for regional gray matter volume.
There was an inverse association between ASOBPR and probability of dementia diagnosis (9% lower probability for each % point higher ASOBPR: OR 0.91, CI95% = 0.85-0.98; p = 0.01). Associations were similar in the subgroup with neuroimaging before and after adjustment for regional gray matter volume.
ASOBPR may be an early marker of risk of dementia in older adults living in the community.
体位性血压与认知状态（CS）之间的关联已有描述，但结果相互矛盾。
我们假设长期暴露于较低的体位性血压与晚年较差的认知状态有关，且参与自主神经功能中枢调节的区域萎缩介导了这些关联。
在一个老龄化纵向队列中，于1997年至2003年获取了三到四次体位性血压测量值，并计算平均收缩期体位性血压反应（ASOBPR），即站立一分钟后测量的收缩压从坐位到站立位的变化百分比。2010年至2012年由临床医生判定认知状态（n = 240；年龄 = 87.1±2.6；59%为女性；37%为黑人），其中一个亚组同时进行了结构神经影像学检查（n = 129）。测量了与自主神经功能相关区域的灰质体积。使用多项回归比较认知功能正常者与诊断为轻度认知障碍或痴呆者的ASOBPR，并控制人口统计学特征、坐位血压轨迹、心血管风险/事件发生率以及1997年至2012年测量的药物使用情况。在进行神经影像学检查的亚组中，在调整区域灰质体积前后重复进行模型分析。
ASOBPR与痴呆诊断概率之间存在负相关（ASOBPR每升高1个百分点，痴呆诊断概率降低9%：OR 0.91，CI95% = 0.85 - 0.9)。在调整区域灰质体积前后，神经影像学亚组中的关联相似。
ASOBPR可能是社区老年人痴呆风险的早期标志物。
