Konwar Srijan, Manca Riccardo, De Marco Matteo, Soininen Hilkka, Venneri Annalena
Department of Life Sciences, Brunel University London, Uxbridge, United Kingdom.
Department of Medicine and Surgery, University of Parma, Parma, Italy.
Front Aging Neurosci. 2023 Jun 21;15:1096798. doi: 10.3389/fnagi.2023.1096798. eCollection 2023.
Physical activity is a modifiable lifestyle factor that has been previously associated with reduced vascular burden and reduced risk of dementia.
This study tested whether physical activity (i.e., being inactive vs. active) contributed to preservation of white matter microstructure in healthy aging controls and patients in prodromal to mild Alzheimer's disease with low/high vascular burden.
A total of 213 participants were recruited from memory clinics. They were classified as being either physically active ( = 113) or inactive ( = 100) based on the Cardiovascular Risk Factors, Aging and Dementia (CAIDE) questionnaire. Diffusion-weighted images were acquired for all participants and pre-processed based on a standard protocol.
A factorial design using voxel-wise tract-based spatial statistics (TBSS) was adopted, with 5,000 permutations and threshold-free cluster enhancement (TFCE), to identify significant clusters for fractional anisotropy (FA), axial diffusivity (AxD), mean diffusivity (MD), and radial diffusivity (RD).
Clusters of higher FA and lower AxD, MD, and RD values were found for physically active compared with inactive participants that were widespread covering mainly association and projection tracts but also some commissural tracts. A three-way Group × Physical Activity × Vascular Burden interaction effect was found for FA mostly in a variety of projection tracts with a right predominance, and some commissural and association tracts. analyses revealed higher FA in patients with high vascular burden who were physically active compared with those patients with high vascular burden who were inactive mainly in projection and association/limbic tracts with a right predominance. Additionally, higher FA was observed in physically active patients with high vascular burden as compared with physically inactive controls with high vascular burden, mainly in bilateral projection fibers and cerebellar regions.
Voxel-wise TBSS analysis revealed better preservation of white matter microstructure that was prominent in the high-risk group such as the patients with high vascular burden, specifically those who were physically active. The beneficial effects of physical activity on white matter microstructure were not observed in the controls.
身体活动是一种可改变的生活方式因素，此前已被证明与减轻血管负担和降低痴呆风险有关。
本研究旨在测试身体活动（即不活动与活动）是否有助于在健康的衰老对照人群以及前驱至轻度阿尔茨海默病且血管负担低/高的患者中保存白质微观结构。
从记忆诊所招募了总共213名参与者。根据心血管危险因素、衰老和痴呆（CAIDE）问卷，他们被分为身体活动组（n = 113）或不活动组（n = 100）。为所有参与者采集了扩散加权图像，并根据标准方案进行预处理。
采用基于体素的纤维束空间统计（TBSS）的析因设计，进行5000次排列和无阈值聚类增强（TFCE），以识别分数各向异性（FA）、轴向扩散率（AxD）、平均扩散率（MD）和径向扩散率（RD）的显著聚类。
与不活动的参与者相比，身体活动的参与者发现了更高FA值以及更低AxD、MD和RD值的聚类，这些聚类广泛分布，主要覆盖联合纤维束和投射纤维束，但也包括一些连合纤维束。在FA方面发现了一个三组交互作用：组×身体活动×血管负担，主要在各种投射纤维束（右侧占优势）以及一些连合纤维束和联合纤维束中。分析显示，与血管负担高且不活动的患者相比，血管负担高且身体活动的患者在主要为右侧占优势的投射纤维束和联合/边缘纤维束中FA更高。此外，与血管负担高且身体不活动的对照相比，血管负担高且身体活动的患者中观察到更高的FA，主要在双侧投射纤维和小脑区域。
基于体素的TBSS分析显示，白质微观结构得到了更好的保存，这在高风险组中很突出，如血管负担高的患者，特别是那些身体活动的患者。在对照组中未观察到身体活动对白质微观结构的有益影响。
