Breidenbach B M, Driscoll I, Glittenberg M P, Paulsen A J, Fernandes-Taylor S, Naren T, Roberts G S, Brach T L, Jarchow M M, Symanski L E, Gaul A Y, Lose S R, Rivera-Rivera L A, Johnson S C, Asthana S, Christian B T, Cook D B, Wieben O, Okonkwo O C
medRxiv. 2025 Mar 4:2025.03.03.25323254. doi: 10.1101/2025.03.03.25323254.
Central arterial stiffness and cerebral blood flow (CBF) are inversely related. Poor cardiorespiratory fitness (CRF) and low physical activity (PA) are related to both higher arterial stiffness and lower CBF. The present study examined (i) whether CRF or PA moderate the relationship between arterial stiffness and CBF and (ii) whether the intensity or the type of PA need to be considered.
Participants (N=78, Mean =64.2±6.14, 72% female) from the Wisconsin Registry for Alzheimer's Prevention and the Wisconsin Alzheimer's Disease Research Center were categorized into low, average and high fitness groups based on maximal graded exercise treadmill test performance. PA was assessed using the CHAMPS questionnaire. Based on hours/week, participants were classified as meeting the recommended 2.5 hours of moderate intensity PA per week (PA Rec Met). Weekly hours of moderate and low intensity PA were calculated as activities of > 3 or < 3 metabolic equivalents, respectively. Activity type was categorized as exercise-, sports/leisure- and work-related. Arterial stiffness was measured as aortic pulse wave velocity (aoPWV) by 2D phase contrast MRI. CBF was assessed by 4D flow MRI in the internal carotid arteries (ICAs), cavernous ICAs, middle cerebral arteries (MCAs), and via two composite measures of total and global flow.
The association between aoPWV and CBF differed by fitness levels, with a negative relationship in the low fitness group and positive relationships in the average and high fitness groups (all s<0.05). Significant moderating effects on the relationships between aoPWV and CBF were also observed for PA Rec Met (all s<0.05), moderate intensity ( =0.05) and exercise-related (all s<0.02) PA.
Average or high fitness, meeting the PA guidelines, and more specifically, moderate intensity and exercise-related PA seem to attenuate the negative relationship between aoPWV on CBF.
中心动脉僵硬度与脑血流量（CBF）呈负相关。心肺适能（CRF）差和体力活动（PA）水平低与较高的动脉僵硬度和较低的CBF均相关。本研究调查了：（i）CRF或PA是否会调节动脉僵硬度与CBF之间的关系；（ii）是否需要考虑PA的强度或类型。
来自威斯康星州阿尔茨海默病预防登记处和威斯康星州阿尔茨海默病研究中心的参与者（N = 78，平均年龄=64.2±6.14岁，72%为女性）根据最大分级运动平板试验表现被分为低、中、高适能组。使用CHAMPS问卷评估PA。根据每周的小时数，参与者被分类为达到每周推荐的2.5小时中等强度PA（PA推荐达标）。中等强度和低强度PA的每周小时数分别按代谢当量>3或<3的活动来计算。活动类型分为与运动、体育/休闲和工作相关。通过二维相位对比MRI测量动脉僵硬度，以主动脉脉搏波速度（aoPWV）表示。通过对颈内动脉（ICA）、海绵窦段ICA、大脑中动脉（MCA）进行四维血流MRI以及通过总血流和整体血流的两个综合指标来评估CBF。
aoPWV与CBF之间的关联因适能水平而异，在低适能组中呈负相关，在中等适能组和高适能组中呈正相关（所有P值<0.05）。对于PA推荐达标（所有P值<0.05）、中等强度（P = 0.05）和与运动相关的PA（所有P值<0.02），也观察到对aoPWV与CBF之间关系有显著的调节作用。
中等适能或高适能、达到PA指南要求，更具体地说，中等强度和与运动相关的PA似乎会减弱aoPWV与CBF之间的负相关关系。
