Klages Jennifer D, Fisk John D, Rockwood Kenneth
Department of Psychology, Dalhousie University, Halifax, Canada.
Dement Geriatr Cogn Disord. 2003;15(1):1-5. doi: 10.1159/000066670.
This study examined the relation between two risks for Alzheimer's disease (AD): the apolipoprotein (APOE) epsilon4 allele and poor memory test performance.
In the Canadian Study of Health and Aging (CSHA), a 5-year longitudinal population-based study that screened and followed over 10,000 participants, 2,914 had an initial clinical assessment and 1,624 had APOE genotype testing. All participants were categorized as having no cognitive impairment, cognitive impairment but no dementia, or dementia at both baseline and follow-up. We examined those (n = 209) with a complete neuropsychological assessment at baseline and no evidence of cognitive impairment who had either APOE epsilon3/epsilon3 or epsilon3/epsilon4 genotypes and who had a clinical consensus diagnosis of either no cognitive impairment or AD at follow-up. Delayed free recall memory was evaluated at CSHA-1 with the Buschke Cued Recall Test (BCRT).
The risk of AD at follow-up was increased for participants with an APOE epsilon3/epsilon4 genotype when memory test performance was not considered, but logistic regression demonstrated that a model which also considered baseline memory test performance was more predictive of AD. In the more complete model, reduced BCRT free recall scores were associated with an increased risk of AD, whereas the risk associated with the APOE epsilon3/epsilon4 genotype was no longer significant.
For those with no evidence of cognitive impairment, drawn from a population-based sample of elderly persons, the APOE epsilon3/epsilon4 genotype was only associated with an increased risk of AD after 5 years if their memory test performance was relatively poor at baseline. Regardless of the APOE genotype, and in the absence of clinical evidence of cognitive impairment, reduced scores on a test of delayed free recall at baseline was associated with an increased risk of AD after 5 years.
本研究探讨了阿尔茨海默病（AD）的两种风险因素之间的关系，即载脂蛋白（APOE）ε4等位基因与记忆测试表现不佳。
在加拿大健康与老龄化研究（CSHA）中，这是一项为期5年的基于人群的纵向研究，对10000多名参与者进行了筛查和随访，其中2914人进行了初始临床评估，1624人进行了APOE基因型检测。所有参与者在基线和随访时均被分类为无认知障碍、有认知障碍但无痴呆或患有痴呆。我们研究了那些（n = 209）在基线时进行了完整神经心理学评估且无认知障碍证据的人，他们具有APOE ε3/ε3或ε3/ε4基因型，并且在随访时临床共识诊断为无认知障碍或AD。在CSHA-1时使用布施克线索回忆测试（BCRT）评估延迟自由回忆记忆。
在不考虑记忆测试表现的情况下，APOE ε3/ε4基因型参与者在随访时患AD的风险增加，但逻辑回归表明，同时考虑基线记忆测试表现的模型对AD的预测性更强。在更完整的模型中，BCRT自由回忆分数降低与AD风险增加相关，而与APOE ε3/ε4基因型相关的风险不再显著。
对于从老年人群体样本中选取的无认知障碍证据的人，只有在基线时记忆测试表现相对较差的情况下，APOE ε3/ε4基因型才与5年后患AD的风险增加相关。无论APOE基因型如何，在无认知障碍临床证据的情况下，基线时延迟自由回忆测试分数降低与5年后患AD的风险增加相关。
