Lu Kirsty, Nicholas Jennifer M, James Sarah-Naomi, Lane Christopher A, Parker Thomas D, Keshavan Ashvini, Keuss Sarah E, Buchanan Sarah M, Murray-Smith Heidi, Cash David M, Sudre Carole H, Malone Ian B, Coath William, Wong Andrew, Henley Susie M D, Fox Nick C, Richards Marcus, Schott Jonathan M, Crutch Sebastian J
Dementia Research Centre UCL Queen Square Institute of Neurology, University College London London UK.
Department of Medical Statistics London School of Hygiene and Tropical Medicine London UK.
Alzheimers Dement (Amst). 2020 Aug 10;12(1):e12076. doi: 10.1002/dad2.12076. eCollection 2020.
We investigated whether life-course factors and neuroimaging biomarkers of Alzheimer's disease pathology predict reaction time (RT) performance in older adults.
Insight 46 study participants, all born in the same week in 1946 (n = 501; ages at assessment = 69 to 71 years), completed a 2-choice RT task and amyloid beta (Aβ) positron emission tomography and MR imaging. We tested for associations between task outcomes (RT; error rate; intra-individual variability in RT) and life-course predictors including childhood cognitive ability and education. In a subsample of 406 cognitively normal participants, we investigated associations between task outcomes and biomarkers including Aβ-positivity.
Cognitively normal Aβ-positive participants had 10% more variable RTs than Aβ-negative participants, despite having similar mean RTs. Childhood cognitive ability and education independently predicted task performance.
This study provides novel evidence that Aβ pathology is associated with poorer consistency of RT in cognitively normal older adults, at an age when dementia prevalence is still very low.
我们研究了阿尔茨海默病病理的生命历程因素和神经影像学生物标志物是否能预测老年人的反应时间（RT）表现。
“洞察46”研究的参与者均于1946年同一周出生（n = 501；评估时年龄为69至71岁），完成了二选一RT任务以及淀粉样β蛋白（Aβ）正电子发射断层扫描和磁共振成像。我们测试了任务结果（RT；错误率；RT的个体内变异性）与生命历程预测因素（包括儿童期认知能力和教育程度）之间的关联。在406名认知正常的参与者子样本中，我们研究了任务结果与生物标志物（包括Aβ阳性）之间的关联。
认知正常的Aβ阳性参与者的RT变异性比Aβ阴性参与者高10%，尽管他们的平均RT相似。儿童期认知能力和教育程度独立预测任务表现。
本研究提供了新的证据，表明在痴呆症患病率仍然很低的年龄，Aβ病理与认知正常的老年人RT一致性较差有关。
