Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
Department of Neurology, Inje University College of Medicine, Haeundae Paik Hospital, Busan, Korea.
Alzheimers Res Ther. 2021 Feb 19;13(1):48. doi: 10.1186/s13195-021-00787-7.
The presence of ß-amyloid (Aß) in the brain can be identified using amyloid PET. In clinical practice, the amyloid PET is interpreted based on dichotomous visual rating, which renders focal Aß accumulation be read as positive for Aß. However, the prognosis of patients with focal Aß deposition is not well established. Thus, we investigated cognitive trajectories of patients with focal Aß deposition.
We followed up 240 participants (112 cognitively unimpaired [CU], 78 amnestic mild cognitive impairment [aMCI], and 50 Alzheimer's disease (AD) dementia [ADD]) for 2 years from 9 referral centers in South Korea. Participants were assessed with neuropsychological tests and F-flutemetamol (FMM) positron emission tomography (PET). Ten regions (frontal, precuneus/posterior cingulate (PPC), lateral temporal, parietal, and striatum of each hemisphere) were visually examined in the FMM scan, and participants were divided into three groups: No-FMM, Focal-FMM (FMM uptake in 1-9 regions), and Diffuse-FMM. We used mixed-effects model to investigate the speed of cognitive decline in the Focal-FMM group according to the cognitive level, extent, and location of Aß involvement, in comparison with the No- or Diffuse-FMM group.
Forty-five of 240 (18.8%) individuals were categorized as Focal-FMM. The rate of cognitive decline in the Focal-FMM group was faster than the No-FMM group (especially in the CU and aMCI stage) and slower than the Diffuse-FMM group (in particular in the CU stage). Within the Focal-FMM group, participants with FMM uptake to a larger extent (7-9 regions) showed faster cognitive decline compared to those with uptake to a smaller extent (1-3 or 4-6 regions). The Focal-FMM group was found to have faster cognitive decline in comparison with the No-FMM when there was uptake in the PPC, striatum, and frontal cortex.
When predicting cognitive decline of patients with focal Aß deposition, the patients' cognitive level, extent, and location of the focal involvement are important.
β-淀粉样蛋白（Aβ）在大脑中的存在可以通过淀粉样 PET 进行识别。在临床实践中，淀粉样 PET 是基于二分视觉评分进行解释的，这使得局灶性 Aβ 积累被解读为 Aβ 阳性。然而，局灶性 Aβ 沉积患者的预后尚未得到很好的确定。因此，我们研究了局灶性 Aβ 沉积患者的认知轨迹。
我们从韩国的 9 个转诊中心招募了 240 名参与者（112 名认知正常[CU]、78 名遗忘型轻度认知障碍[aMCI]和 50 名阿尔茨海默病[AD]痴呆[ADD]），进行了为期 2 年的随访。参与者接受了神经心理学测试和 F-氟代美金刚（FMM）正电子发射断层扫描（PET）检查。在 FMM 扫描中对 10 个区域（每个半球的额叶、后扣带回/顶叶（PPC）、外侧颞叶、顶叶和纹状体）进行了视觉检查，参与者被分为三组：无 FMM、局灶性 FMM（FMM 摄取 1-9 个区域）和弥漫性 FMM。我们使用混合效应模型，根据 Aβ 受累的认知水平、程度和位置，比较 Focal-FMM 组与 No-或 Diffuse-FMM 组的认知衰退速度。
240 名参与者中有 45 名（18.8%）被归类为 Focal-FMM。与 No-FMM 组相比，Focal-FMM 组的认知衰退速度更快（尤其是在 CU 和 aMCI 阶段），但比 Diffuse-FMM 组更慢（特别是在 CU 阶段）。在 Focal-FMM 组中，与摄取较少（1-3 或 4-6 个区域）的患者相比，摄取较多（7-9 个区域）的患者认知衰退速度更快。与 No-FMM 相比，当 PPC、纹状体和额叶皮质有摄取时，Focal-FMM 组的认知衰退速度更快。
在预测局灶性 Aβ 沉积患者的认知下降时，患者的认知水平、局灶性受累的程度和位置是重要的。
