Centre for Mental Health Research, Building 63, Eggleston Road, The Australian National University, Canberra ACT 0200, Australia.
Psychol Aging. 2011 Jun;26(2):339-50. doi: 10.1037/a0021845.
Differences in the time of onset and magnitude of terminal decline were examined in three cognitive domains: processing speed, episodic memory, and global function. In addition, cognitive reserve was investigated by testing whether education affected the onset or rate of decline across these domains. Eight hundred ninety-six community-dwelling Australian adults aged ≥ 70 years were assessed up to four times over 12 years, with vital status followed for 17 years. For each of the cognitive measures, a series of change point models were fitted across the 20 years before death to find the optimal point at which terminal decline was distinguished from preterminal decline. Change points were then assessed separately for high- and low-education groups. The change points were 8.5 years for processing speed (95% CI: 6.0-11.2 years), 7.1 years for global function (6.2-9.3), and 6.6 years for episodic memory (5.3-7.1). The rate of decline was two to four times greater in the terminal phase relative to the preterminal phase, depending on the domain. Increased education changed the terminal decline effect differently for each of the three tests, either by significantly hastening the onset of terminal decline and decreasing the rate of decline, or by increasing the rate of either preterminal or terminal decline. Analyses were repeated excluding participants diagnosed with dementia, with no substantive change to the outcomes. In conclusion, the rate and onset of terminal decline varied somewhat across cognitive domains. Education affected terminal decline differently across the domains, but this modification was not consistent with the predictions of cognitive reserve theory.
处理速度、情景记忆和整体功能，检查了终末期下降的发病时间和幅度的差异。此外，通过测试教育是否影响这些领域的发病或下降速度，研究了认知储备。896 名年龄≥70 岁的澳大利亚社区居民在 12 年内接受了多达 4 次评估，随访时间长达 17 年。对于每个认知指标，在死亡前 20 年进行了一系列转折点模型拟合，以找到区分终末期下降和前期下降的最佳点。然后分别评估高教育和低教育组的转折点。处理速度的转折点为 8.5 年（95%CI：6.0-11.2 年），整体功能为 7.1 年（6.2-9.3），情景记忆为 6.6 年（5.3-7.1）。终末期下降的速度比前期下降快 2 到 4 倍，具体取决于领域。增加教育对三个测试中的每一个都改变了终末期下降的影响，要么通过显著加快终末期下降的发病并降低下降速度，要么通过增加前期或终末期下降的速度。在排除了被诊断患有痴呆症的参与者后，重复了分析，结果没有实质性变化。总之，认知领域的终末期下降的速度和发病时间略有不同。教育对不同领域的终末期下降的影响不同，但这种改变与认知储备理论的预测不一致。
