Machulda Mary M, Lundt Emily S, Mester Carly T, Albertson Sabrina M, Raghavan Sheelakumari, Reid Robert I, Schwarz Christopher G, Graff-Radford Jonathan, Jack Clifford R, Knopman David S, Mielke Michelle M, Kremers Walter K, Petersen Ronald C, Bondi Mark W, Vemuri Prashanthi
Division of Neurocognitive Disorders Department of Psychiatry and Psychology Mayo Clinic Rochester Minnesota USA.
Division of Biomedical Statistics and Informatics Department of Health Sciences Research Mayo Clinic Rochester Minnesota USA.
Alzheimers Dement (Amst). 2021 Dec 31;13(1):e12269. doi: 10.1002/dad2.12269. eCollection 2021.
The aim of this study was to examine white matter hyperintensities (WMH) and fractional anisotropy (FA) in empirically derived incident mild cognitive impairment (MCI) subtypes.
We evaluated 188 participants with incident MCI in the Mayo Clinic Study of Aging (MCSA) identified as having one of four cluster-derived subtypes: subtle cognitive impairment, amnestic, dysnomic, and dysexecutive. We used linear regression models to evaluate whole brain and regional WMH volumes. We examined fractional anisotropy (FA) on a subset of 63 participants with diffusion tensor imaging.
Amnestic and dysexecutive subtypes had higher WMH volumes in differing patterns than cognitively unimpaired; the dysexecutive subtype had higher WMH than subtle cognitive impairment. There was widespread WM degeneration in long association and commissural fibers in the amnestic, dysnomic, and dysexecutive subtypes, and corpus callosum FA accounted for significant variability in global cognition.
White matter changes likely contribute to cognitive symptoms in incident MCI.
本研究旨在探讨经验性得出的新发轻度认知障碍（MCI）亚型中的白质高信号（WMH）和分数各向异性（FA）。
我们在梅奥诊所衰老研究（MCSA）中评估了188名新发MCI参与者，他们被确定为具有四种聚类衍生亚型之一：轻微认知障碍、遗忘型、命名障碍型和执行功能障碍型。我们使用线性回归模型来评估全脑和区域WMH体积。我们对63名参与者的子集进行扩散张量成像检查分数各向异性（FA）。
遗忘型和执行功能障碍型亚型的WMH体积比认知未受损者有不同模式的增加；执行功能障碍型亚型的WMH高于轻微认知障碍。在遗忘型、命名障碍型和执行功能障碍型亚型中，长联合纤维和连合纤维存在广泛的白质变性，胼胝体FA在整体认知中占显著变异性。
白质变化可能导致新发MCI的认知症状。
