Buchman Aron S, Yu Lei, Wilson Robert S, Boyle Patricia A, Schneider Julie A, Bennett David A
Rush Alzheimer's Disease Center, Department of Neurological Sciences,
Rush Alzheimer's Disease Center, Department of Neurological Sciences.
J Gerontol A Biol Sci Med Sci. 2014 Dec;69(12):1536-44. doi: 10.1093/gerona/glu117. Epub 2014 Aug 18.
First, we tested the hypothesis that the rate of change of physical frailty and cognitive function in older adults are correlated. Next, we examined if their rates of change are associated with the same brain pathologies.
About 2,167 older adults participating in the Religious Orders Study and the Rush Memory and Aging Project had annual clinical evaluations. Bivariate random coefficient models were used to estimate simultaneously the rates of change in both frailty and cognition, and the correlation of change was characterized by a joint distribution of the random effects. Then, we examined whether postmortem indices from deceased were associated with the rate of change of frailty and cognition.
During an average follow-up of 6 years, frailty worsened by 0.09 unit/y and cognition declined by 0.08 unit/y. Most individuals showed worsening frailty and cognition (82.8%); 17% showed progressive frailty alone and <1% showed only cognitive decline. The rates of change of frailty and cognition were strongly correlated (ρ = -0.73, p < .001). Among deceased (N = 828), Alzheimer's disease pathology, macroinfarcts, and nigral neuronal loss showed independent associations with the rate of change in both frailty and cognition (all ps < .001). In these models, demographics explained about 9% of the variation in individual rate of change in frailty, and neuropathologies explained about 8%. In contrast, demographics and neuropathologies accounted for 2% and 30%, respectively, of the variance in the cognitive decline.
The rates of change in frailty and cognition are strongly correlated and this may be due in part because they share a common pathologic basis.
首先，我们检验了老年人身体衰弱和认知功能的变化率相关这一假设。其次，我们研究了它们的变化率是否与相同的脑病理状况相关。
约2167名参与宗教团体研究及拉什记忆与衰老项目的老年人接受了年度临床评估。使用双变量随机系数模型同时估计衰弱和认知的变化率，变化的相关性通过随机效应的联合分布来表征。然后，我们研究了已故者的尸检指标是否与衰弱和认知的变化率相关。
在平均6年的随访期间，衰弱每年恶化0.09个单位，认知每年下降0.08个单位。大多数个体表现出衰弱和认知恶化（82.8%）；17%仅表现出衰弱进展，不到1%仅表现出认知下降。衰弱和认知的变化率密切相关（ρ = -0.73，p < .001）。在已故者（N = 828）中，阿尔茨海默病病理、大面积梗死和黑质神经元丢失与衰弱和认知的变化率均显示出独立相关性（所有p值 < .001）。在这些模型中，人口统计学因素解释了个体衰弱变化率中约9%的变异，神经病理学因素解释了约8%。相比之下，人口统计学因素和神经病理学因素分别占认知下降方差的2%和30%。
衰弱和认知的变化率密切相关，这可能部分归因于它们具有共同的病理基础。
