Maruff P, Collie A, Darby D, Weaver-Cargin J, Masters C, Currie Jon
Mental Health Research Institute of Victoria, Carlton, Australia.
Dement Geriatr Cogn Disord. 2004;18(3-4):342-8. doi: 10.1159/000080229. Epub 2004 Aug 13.
Screening of normal older persons for progressive memory decline is a worthwhile strategy in the pursuit of the earliest possible stages of pre-clinical Alzheimer's disease (AD) or mild cognitive impairment (MCI). Reliable tests are needed to both detect MCI and measure the natural history of decline over months rather than years. We aimed to detect memory decline over 1 year in a group of older individuals with well-characterised amnestic MCI.
The continuous learning task (CLT) from the CogState test battery was administered 8 times in 12 months to 15 individuals with MCI and 35 controls matched for age, education, IQ and gender. All subjects were recruited from an ongoing aging study. The rate of change in CLT performance over the year was compared between groups and also compared to that detected with a word list learning task and a computerised paired associate learning task.
At baseline, memory performance in the amnestic MCI group was significantly worse than controls on all memory tests. However, at 12 months the magnitude of the difference between the groups had increased significantly on the CLT due to decline in memory accuracy in the MCI group. No decline over 12 months was detectable on the routine memory tests.
Subtle memory decline is detectable in amnestic MCI using reliable and sensitive tests of memory. Such measures may assist in the early identification of AD and also in trials of putative disease-modifying therapies to be conducted over as little as 12 months.
对正常老年人进行渐进性记忆衰退筛查，是在临床前阿尔茨海默病（AD）或轻度认知障碍（MCI）尽可能早的阶段进行探索的一项有价值的策略。需要可靠的测试来检测MCI并测量数月而非数年的衰退自然史。我们旨在检测一组具有明确遗忘型MCI的老年人在1年内的记忆衰退情况。
对15名MCI患者和35名年龄、教育程度、智商和性别相匹配的对照者，在12个月内进行8次CogState测试电池中的连续学习任务（CLT）。所有受试者均来自一项正在进行的衰老研究。比较两组之间CLT表现的年变化率，并与单词列表学习任务和计算机化配对联想学习任务检测到的变化率进行比较。
在基线时，遗忘型MCI组在所有记忆测试中的记忆表现均显著低于对照组。然而，在12个月时，由于MCI组记忆准确性下降，两组之间的差异幅度在CLT上显著增加。在常规记忆测试中未检测到12个月内的衰退。
使用可靠且敏感的记忆测试可在遗忘型MCI中检测到细微的记忆衰退。这些措施可能有助于AD的早期识别，也有助于在仅12个月内进行的假定疾病修饰疗法试验。
