Amieva Hélène, Letenneur Luc, Dartigues Jean-François, Rouch-Leroyer Isabelle, Sourgen Christophe, D'Alchée-Birée Françoise, Dib Michel, Barberger-Gateau Pascale, Orgogozo Jean-Marc, Fabrigoule Colette
INSERM Unit 593, Université Victor Ségalen, Bordeaux, France.
Dement Geriatr Cogn Disord. 2004;18(1):87-93. doi: 10.1159/000077815. Epub 2004 Apr 14.
Elderly subjects diagnosed with mild cognitive impairment (MCI) are becoming the target of intervention trials. The criteria used for MCI are principally issued from prospective clinical studies, although longitudinal population-based studies having identified several cognitive predictors of dementia can be of great contribution in the definition of these criteria. This study was conducted to explore the external validity of MCI criteria issued from a longitudinal population-based study, and subsequently to identify the best predictors of the short-term conversion to Alzheimer's disease 2 years after the MCI diagnosis. Ninety elderly volunteers with memory complaint diagnosed with MCI on the basis of their functional and neuropsychological performances were followed up within 2 years. The potential predictors of the conversion to dementia collected at baseline included age, gender, educational level, size of temporal lobe, apolipoprotein E genotype and a series of neuropsychological measures (Mac Nair Scale, Mini-Mental State Examination, Benton Visual Retention Test, Isaacs Set Test, Digit Symbol Substitution Task, Letter Cancellation Task, digit span tasks and finger-tapping test). Within the 2 years, 29 subjects (32.2%) presented a conversion to dementia. The risk of conversion to dementia was associated with age and size of temporal lobe but not with gender, education, or apolipoprotein E4 genotype. Several neuropsychological measures were associated with the risk of conversion to dementia, but in a logistic regression performed with the significant variables found in the univariate analysis, only the Letter Cancellation Test was shown to be an independent predictor. In conclusion, the quite elevated conversion rates obtained show the usefulness, when defining MCI criteria, of considering not only memory impairment but also impairment in other cognitive areas, as well as mild impairment on higher-order activities of daily living. Among the variables considered, the Letter Cancellation Test proved to be a major predictor of short-term conversion to dementia.
被诊断为轻度认知障碍（MCI）的老年受试者正成为干预试验的对象。MCI的诊断标准主要源自前瞻性临床研究，尽管基于人群的纵向研究已确定了痴呆症的若干认知预测因素，这些研究对这些标准的定义有很大帮助。本研究旨在探讨基于人群的纵向研究中MCI标准的外部效度，并随后确定MCI诊断后2年短期转化为阿尔茨海默病的最佳预测因素。90名有记忆问题的老年志愿者根据其功能和神经心理学表现被诊断为MCI，并在2年内进行随访。基线时收集的转化为痴呆症的潜在预测因素包括年龄、性别、教育水平、颞叶大小、载脂蛋白E基因型以及一系列神经心理学测量（麦克奈尔量表、简易精神状态检查表、本顿视觉保持测验、艾萨克斯成套测验、数字符号替换任务、字母划消任务、数字广度任务和手指敲击测试）。在这2年内，29名受试者（32.2%）转化为痴呆症。转化为痴呆症的风险与年龄和颞叶大小有关，而与性别、教育程度或载脂蛋白E4基因型无关。若干神经心理学测量与转化为痴呆症风险有关，但在单变量分析中发现的显著变量进行logistic回归时，只有字母划消测验被证明是一个独立预测因素。总之，获得的相当高的转化率表明，在定义MCI标准时，不仅要考虑记忆障碍，还要考虑其他认知领域的障碍以及日常生活高阶活动中的轻度障碍是有用的。在所考虑的变量中，字母划消测验被证明是短期转化为痴呆症的主要预测因素。
