健康衰老过程中与心肺适能相关的白质完整性区域网络协方差模式
Regional network covariance patterns of white matter integrity related to cardiorespiratory fitness in healthy aging.
作者信息
Smith Samantha G, Bharadwaj Pradyumna K, Raichlen David A, Grilli Matthew D, Andrews-Hanna Jessica R, Hishaw Georg A, Huentelman Matthew J, Trouard Theodore P, Alexander Gene E
机构信息
Department of Psychology, University of Arizona, Tucson, AZ, United States.
Evelyn F. McKnight Brain Institute, University of Arizona, Tucson, AZ, United States.
出版信息
Front Aging Neurosci. 2025 Jun 26;17:1542458. doi: 10.3389/fnagi.2025.1542458. eCollection 2025.
Cardiorespiratory fitness (CRF), measured by VOmax, is an indicator of vascular functioning that can influence the integrity of brain microstructural white matter tracts in aging. How CRF is related to regional patterns of white matter bundles for magnetic resonance imaging (MRI) diffusion metrics (axial diffusivity, AD; radial diffusivity, RD; mean diffusivity, MD; fractional anisotropy, FA) has been less studied. We used a multivariate analysis method, the Scaled Subprofile Model (SSM), to identify network patterns of MRI tract-specific white matter integrity (WMI) for AD, RD, MD, and FA related to VOmax and to evaluate their relation to demographic, vascular health, and dementia risk factors in 167 cognitively unimpaired older adults, ages 50 to 88. We identified four CRF-related regional patterns of WMI characterized by enhanced integrity in commissural pathways that connect areas within anterior brain regions (prefrontal body of the corpus callosum), connect subcortical regions to one another (fornix), and include selected association tracts (arcuate fasciculus, superior longitudinal fasciculus). Greater white matter lesion load, in addition to age, was associated with reduced expression of all four CRF-WMI patterns, while high vascular risk level was further associated with reduced expression of the RD, MD, and FA patterns. The regional patterns of RD and FA were most strongly associated with CRF. The results suggest that in healthy older adults, enhanced CRF is differentially associated with regional patterns of WMI, which are related to age and further impacted by macrostructural white matter lesion load and vascular risk. These findings support the use of the multivariate SSM in identifying regional patterns of white matter tracts that may provide markers of brain aging and cerebrovascular health.
通过最大摄氧量(VOmax)测量的心肺适能(CRF)是血管功能的一个指标,它会影响衰老过程中脑微结构白质束的完整性。关于CRF与磁共振成像(MRI)扩散指标(轴向扩散率,AD;径向扩散率,RD;平均扩散率,MD;分数各向异性,FA)的白质束区域模式之间的关系,研究较少。我们使用了一种多变量分析方法,即缩放子轮廓模型(SSM),来识别与VOmax相关的AD、RD、MD和FA的MRI特定脑区白质完整性(WMI)的网络模式,并在167名年龄在50至88岁、认知未受损的老年人中评估它们与人口统计学、血管健康和痴呆风险因素的关系。我们确定了四种与CRF相关的WMI区域模式,其特征是连接前脑区域内各区域(胼胝体额叶)的连合通路、相互连接皮质下区域(穹窿)以及包括选定联合束(弓状束、上纵束)的白质完整性增强。除年龄外,更大的白质病变负荷与所有四种CRF-WMI模式的表达降低有关,而高血管风险水平进一步与RD、MD和FA模式的表达降低有关。RD和FA的区域模式与CRF的关联最为强烈。结果表明,在健康老年人中,增强的CRF与WMI的区域模式存在差异关联,这些模式与年龄有关,并进一步受到宏观结构白质病变负荷和血管风险的影响。这些发现支持使用多变量SSM来识别白质束的区域模式,这些模式可能提供脑衰老和脑血管健康的标志物。