Transitions in cognitive test scores over 5 and 10 years in elderly people: evidence for a model of age-related deficit accumulation.
Transitions in cognitive test scores over 5 and 10 years in elderly people: evidence for a model of age-related deficit accumulation.
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DOI：
10.1186/1471-2318-8-3
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发表时间：
2008-02-18
期刊：
影响因子：
4.1
通讯作者：
Rockwood, Kenneth
中科院分区：
文献类型：
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作者：
Mitnitski, Arnold;Rockwood, Kenneth
背景：平均而言，健康状况会随着年龄的增长而恶化，但许多人都有改善的时期。随机模型很好地描述了这种变化是如何发生的。鉴于认知也会随着年龄而变化，我们想知道同一模型是否也可以描述社区老年人认知测试分数错误的累积。 方法：在这项前瞻性队列研究中，对加拿大健康与老龄化研究的 8954 名老年人（基线年龄在 65 岁以上）进行了为期 10 年的跟踪调查。认知状态是根据 100 分的改良最小精神状态检查中的错误数量来定义的。选择错误计数与一般衰老模型中的赤字计数相平行，该模型基于赤字累积。与赤字计数一样，采用了具有 4 个参数的马尔可夫链转换模型。 结果：平均而言，犯错误的机会随着每个时间间隔出现的错误数量而线性增加。认知状态的变化通过修正泊松分布进行高精度描述（R2 = 0.96），使用四个参数：累积额外错误的背景机会、在给定现有数量的情况下发生更多或更少错误的机会，以及相应的背景和死亡增量机会。结论：认知测试中错误数量的变化对应于一个通用模型，该模型还总结了与年龄相关的缺陷变化。该模型考虑了改善和恶化，似乎代表了一种量化健康状况的各个方面如何随年龄变化的临床相关方法。
BACKGROUND: On average, health worsens with age, but many people have periods of improvement. A stochastic model provides an excellent description of how such changes occur. Given that cognition also changes with age, we wondered whether the same model might also describe the accumulation of errors in cognitive test scores in community-dwelling older adults.METHODS: In this prospective cohort study, 8954 older people (aged 65+ at baseline) from the Canadian Study of Health and Aging were followed for 10 years. Cognitive status was defined by the number of errors on the 100-point Modified Min-Mental State Examination. The error count was chosen to parallel the deficit count in the general model of aging, which is based on deficit accumulation. As with the deficit count, a Markov chain transition model was employed, with 4 parameters.RESULTS: On average, the chance of making errors increased linearly with the number of errors present at each time interval. Changes in cognitive states were described with high accuracy (R2 = 0.96) by a modified Poisson distribution, using four parameters: the background chance of accumulating additional errors, the chance of incurring more or fewer errors, given the existing number, and the corresponding background and incremental chances of dying.CONCLUSION: The change in the number of errors in a cognitive test corresponded to a general model that also summarizes age-related changes in deficits. The model accounts for both improvement and deterioration and appears to represent a clinically relevant means of quantifying how various aspects of health status change with age.