Department of Psychiatry, University of California San Diego, La Jolla, CA, USA; Center for Behavior Genetics of Aging, University of California San Diego, La Jolla, CA, USA.
Institute for Molecular Medicine Finland (FIMM), HiLIFE, University of Helsinki, Helsinki, Finland.
Neurobiol Aging. 2020 Oct;94:149-153. doi: 10.1016/j.neurobiolaging.2020.05.015. Epub 2020 Jun 11.
Degree of memory impairment is often used to infer early versus late amnestic mild cognitive impairment (aMCI). Previously, 318 Alzheimer's Disease Neuroimaging Initiative participants with aMCI-determined by a single memory test-were divided based on Rey Auditory Verbal Learning Task (AVLT) delayed recall: AVLT-impaired (n = 225) and AVLT-normal (n = 93). Equally consistent with differential progression or differential diagnosis, the AVLT-impaired group had more abnormal Alzheimer's disease (AD) biomarkers, more neurodegeneration over time, and was more likely to develop AD. In the present study, higher AD polygenic risk scores were associated with increased odds of being AVLT-impaired (odds ratio 1.8, p < 0.001). Thus, impairment severity does not necessarily reflect early versus late aMCI because disease progression cannot alter polygenic risk. Presumed early MCI is likely a heterogeneous category that includes excess false-positives. The additional cognitive test improved diagnostic precision by reducing false positives. Impairment severity may reflect differences in underlying disease risk but cannot be used to infer early versus late MCI based on cross-sectional data alone.
记忆损伤程度常被用于推断早发性和晚发性遗忘型轻度认知障碍（aMCI）。此前，318 名经单一记忆测试确诊为 aMCI 的阿尔茨海默病神经影像学倡议参与者，根据 Rey 听觉言语学习测试（AVLT）的延迟回忆进行分组：AVLT 损伤组（n=225）和 AVLT 正常组（n=93）。同样与进展差异或诊断差异一致的是，AVLT 损伤组有更多异常的阿尔茨海默病（AD）生物标志物，随时间推移有更多神经退行性变，并且更有可能发展为 AD。在本研究中，较高的 AD 多基因风险评分与成为 AVLT 损伤的几率增加相关（优势比 1.8，p<0.001）。因此，损伤严重程度不一定反映早发性和晚发性 aMCI，因为疾病进展不能改变多基因风险。假定的早期 MCI 可能是一个异质类别，其中包括过多的假阳性。额外的认知测试通过减少假阳性提高了诊断精度。损伤严重程度可能反映了潜在疾病风险的差异，但不能仅根据横断面数据推断早发性或晚发性 MCI。
