Wicklund Alissa H, Rademaker Alfred, Johnson Nancy, Weitner Bing Bing, Weintraub Sandra
Department of Psychiatry and Behavioral Sciences, Cognitive Neurology and Alzheimer's Disease Center, Northwestern University, Chicago, IL 60611, USA.
Alzheimer Dis Assoc Disord. 2007 Oct-Dec;21(4):S70-8. doi: 10.1097/WAD.0b013e31815bf8a5.
Progressive decline in cognition is a hallmark feature of dementia, and the rate and profile of cognitive decline has been well characterized in Alzheimer disease (AD). Less is known about decline in cognition over time in other forms of dementia such as the behavioral variant of frontotemporal dementia (FTD) and primary progressive aphasia (PPA). The present study examined rate of cognitive decline across domains of memory, language, and executive function measured by neuropsychologic tests, in AD (n=84), FTD (n=66), and PPA (n=44). Patients were in the mild stages of dementia, with comparable duration of illness at the baseline evaluation. A best linear unbiased predictor (BLUP) analysis was used in which the slope of the relationship between a cognitive measure and time was estimated for each person. AD subjects demonstrated a floor effect on measures of memory at baseline and a decline on measures of language and executive functioning over time. FTD showed the greatest decline over time on the Mini-Mental State Examination, executive functioning, and naming. PPA patients demonstrated prominent decline on language measures, verbal memory measures, and attention. Results suggest that the profile of rate of change over time has unique features on the basis of the type of dementia syndrome. However, there is overlap in the profiles of decline likely influenced by the overlap in cognitive constructs measured by neuropsychologic tests. The comparison of the rate of decline in FTD and PPA may also reflect the neuroanatomic overlap in these syndromes over time.
认知功能的进行性衰退是痴呆症的一个标志性特征，阿尔茨海默病（AD）中认知衰退的速度和特征已得到充分描述。对于其他形式的痴呆症，如行为变异型额颞叶痴呆（FTD）和原发性进行性失语（PPA），认知功能随时间衰退的情况了解较少。本研究考察了通过神经心理学测试测量的AD（n = 84）、FTD（n = 66）和PPA（n = 44）患者在记忆、语言和执行功能领域的认知衰退速度。患者处于痴呆症的轻度阶段，在基线评估时病程相当。采用最佳线性无偏预测器（BLUP）分析，估计每个人认知测量与时间之间关系的斜率。AD患者在基线时记忆测量上表现出下限效应，随着时间推移语言和执行功能测量出现衰退。FTD患者在简易精神状态检查、执行功能和命名方面随时间衰退最为明显。PPA患者在语言测量、言语记忆测量和注意力方面表现出明显衰退。结果表明，根据痴呆症综合征的类型，随时间变化的衰退速度特征具有独特性。然而，衰退特征存在重叠，这可能受到神经心理学测试所测量的认知结构重叠的影响。FTD和PPA衰退速度的比较也可能反映了这些综合征随时间的神经解剖学重叠。
