Gonneaud Julie, Arenaza-Urquijo Eider M, Mézenge Florence, Landeau Brigitte, Gaubert Malo, Bejanin Alexandre, de Flores Robin, Wirth Miranka, Tomadesso Clémence, Poisnel Géraldine, Abbas Ahmed, Desgranges Béatrice, Chételat Gaël
From Neuropsychologie et Imagerie de la Mémoire Humaine, PSL Research University, EPHE, INSERM U1077, CHU de Caen (J.G., E.M.A.-U., F.M., B.L., M.G., A.B., R.d.F., M.W., C.T., G.P., A.A., B.D., G.C.), and INSERM UMR-S U1237, GIP Cyceron (J.G., E.M.A.-U., F.M., B.L., A.B., R.d.F., C.T., G.P., G.C.), UNICAEN, Normandie University, Caen, France.
Neurology. 2017 Dec 12;89(24):2438-2446. doi: 10.1212/WNL.0000000000004733. Epub 2017 Nov 17.
To improve our understanding of early β-amyloid (Aβ) accumulation processes using florbetapir-PET scan in 20- to 60-year-old individuals.
Seventy-six cognitively normal individuals aged 20 to 60 years, 57 cognitively normal older individuals (61-84 years old), and 70 patients with mild cognitive impairment or probable Alzheimer disease (AD) underwent a florbetapir-PET scan. Images were spatially normalized and scaled using the whole cerebellum. The relationship with age was assessed on the mean neocortical standardized uptake value ratio (SUVR) and voxelwise in the younger group to assess early Aβ accumulation processes. To compare the topography of early-age-related vs AD-related changes, Aβ increase in patients vs cognitively normal older adults was also assessed.
A linear increase of Aβ deposition from 20 to 60 years old was found on the mean neocortical SUVR, and more specifically on the temporal neocortex. By contrast, increase in patients predominated in frontal and medial parietal areas. The temporal increase in healthy participants was still significant when including only the 20- to 50-year-old individuals and controlling for several possible methodologic confounds.
Florbetapir binding increases linearly from 20 to 60 years old in the temporal lobe. Pending replication, including with other PET tracers, this study suggests that the well-described medial frontal and parietal accumulation in late adulthood and AD might superimpose to a physiologic accumulation of Aβ, starting from young adulthood, in temporal lobes.
利用氟代贝他吡正电子发射断层扫描（PET），增进我们对20至60岁个体早期β-淀粉样蛋白（Aβ）积累过程的理解。
76名年龄在20至60岁的认知正常个体、57名认知正常的老年个体（61 - 84岁）以及70名轻度认知障碍或可能患有阿尔茨海默病（AD）的患者接受了氟代贝他吡PET扫描。图像使用整个小脑进行空间归一化和缩放。在较年轻组中，通过平均新皮质标准化摄取值比率（SUVR）和体素水平评估与年龄的关系，以评估早期Aβ积累过程。为比较与年龄相关的早期变化和与AD相关变化的地形分布，还评估了患者与认知正常老年成年人中Aβ的增加情况。
在平均新皮质SUVR上，尤其是颞叶新皮质上，发现20至60岁Aβ沉积呈线性增加。相比之下，患者的增加主要在额叶和顶叶内侧区域。仅纳入20至50岁个体并控制几种可能的方法学混杂因素时，健康参与者的颞叶增加仍很显著。
在颞叶中，氟代贝他吡结合从20岁到60岁呈线性增加。在其他PET示踪剂等重复研究之前，本研究表明，在成年晚期和AD中描述详尽的内侧额叶和顶叶积累可能叠加在从青年期开始在颞叶出现的Aβ生理性积累之上。
