Department of Radiology, Mayo Clinic, Rochester, Minnesota, USA.
Department of Neurology, Mayo Clinic, Rochester, Minnesota, USA.
Alzheimers Dement. 2023 Oct;19(10):4396-4406. doi: 10.1002/alz.13396. Epub 2023 Jul 23.
Atypical variants of Alzheimer's disease (AD) include the visual variant, known as posterior cortical atrophy (PCA), and the language variant, known as logopenic progressive aphasia (LPA). Clinically, rates of disease progression differ between them.
We evaluated 34 PCA and 29 LPA participants. Structural magnetic resonance imaging and F-flortaucipir positron emission tomography were performed at baseline and at 1-year follow-up. Rates of change in tau uptake and grey matter volumes were compared between PCA and LPA with linear mixed-effects models and voxel-based analyses.
PCA had faster rates of occipital atrophy. LPA had faster rates of left temporal atrophy and faster rates of tau accumulation in the parietal, right temporal, and occipital lobes. Age was negatively associated with rates of atrophy and tau accumulation.
Longitudinal patterns of neuroimaging abnormalities differed between PCA and LPA, although with divergent results for tau accumulation and atrophy.
The language variant of Alzheimer's disease accumulates tau faster than the visual variant. Each variant shows faster rates of atrophy than the other in its signature regions. Age negatively influences rates of atrophy and tau accumulation in both variants.
阿尔茨海默病（AD）的非典型变体包括视觉变体，称为后部皮质萎缩（PCA），以及语言变体，称为失语法性进行性失语（LPA）。临床上，它们的疾病进展速度不同。
我们评估了 34 名 PCA 和 29 名 LPA 参与者。在基线和 1 年随访时进行结构磁共振成像和 F-flortaucipir 正电子发射断层扫描。使用线性混合效应模型和基于体素的分析比较 PCA 和 LPA 之间 tau 摄取和灰质体积变化率。
PCA 具有更快的枕叶萎缩速度。LPA 具有更快的左侧颞叶萎缩速度，以及更快的顶叶、右侧颞叶和枕叶 tau 积累速度。年龄与萎缩和 tau 积累的速度呈负相关。
尽管 tau 积累和萎缩的结果存在分歧，但 PCA 和 LPA 之间的神经影像学异常的纵向模式不同。
阿尔茨海默病的语言变体比视觉变体更快地积累 tau。每种变体在其特征区域的萎缩速度都比另一种更快。年龄对两种变体的萎缩和 tau 积累速度都有负面影响。
