Blanchet S, McCormick L, Belleville S, Gély-Nargeot M C, Joanette Y
Centre de Recherche, Institut Universitaire de Gériatrie de Montréal, 4565, Chemin Queen-Mary, Montréal H3W 1W5, Canada.
Rev Neurol (Paris). 2002 Jan;158(1):29-39.
The aging of the population leads to increased awareness of problems associated with age-related degenerative dementias. Given that these dementias are progressive in onset, many clinicians and researchers have proposed criteria that allow for the identification of older subjects manifesting cognitive impairment, but not responding to the criteria for dementia. Our knowledge of subjects with mild cognitive impairment is limited; it is, however, established that they present a high risk of developing dementia in the future. Although it is essential to increase our comprehension of their cognitive and functional decline, the study of subjects presenting mild cognitive impairment is compromised due to the existence of numerous non-converging classifications. The goal of the present article is to conduct a critical review of the different classifications of mild cognitive impairment in the elderly in order to attempt to identify the optimal criteria, allowing for a distinction to be made between subjects with mild cognitive impairment, who remain in a stable state and those whose condition evolves to a dementia. These criteria may enable us to describe a homogenuous group of individuals presenting with different rates of dementia risk factors. We present the classifications most frequently used in clinical and research settings. After listing them according to categorial, clinical or dimensional approaches, we performed a critical analysis for each one. Depending on the diagnostic criteria applied, major variations are revealed for the prevalence of cognitive impairment and the incidence of dementia. They are explained by methodological and theoretical shortcomings that we point out and discuss (e.g., reference group, lack of diagnostic criteria or exclusion criteria, high level of subjectivity). Beyond these criticisms, we discuss the challenges to be met in order to reach the optimal identification criteria. Notably, the impact of mild cognitive impairment on daily living activities should be tested with the use of more specific questionnaires/tasks. The goal of the objective definition of cognitive impairment should be to minimize subjectivity in the diagnosis. It is also suggested that sensitive cognitive measures would be used on all aspects of cognition, while recognizing and taking into account all confounding factors (e.g., age, education level). Given the nature and consequences of mild cognitive impairment, an inter-disciplinary approach is suggested (e.g., neurobiological, psychiatric, and genetic cues). A consensus on optimal diagnostic criteria is essential to propose cognitive and pharmacological treatments for the effective prevention of ementia.
人口老龄化导致人们对与年龄相关的退行性痴呆症相关问题的认识不断提高。鉴于这些痴呆症起病呈进行性，许多临床医生和研究人员提出了一些标准，用于识别表现出认知障碍但不符合痴呆症标准的老年受试者。我们对轻度认知障碍患者的了解有限；然而，已经确定他们未来患痴呆症的风险很高。尽管增加对他们认知和功能衰退的理解至关重要，但由于存在众多不一致的分类，对表现出轻度认知障碍的受试者的研究受到了影响。本文的目的是对老年人轻度认知障碍的不同分类进行批判性综述，以试图确定最佳标准，从而区分处于稳定状态的轻度认知障碍患者和病情发展为痴呆症的患者。这些标准可能使我们能够描述一组具有不同痴呆风险因素发生率的同质个体。我们介绍了临床和研究环境中最常用的分类。根据分类、临床或维度方法列出这些分类后，我们对每一种分类进行了批判性分析。根据所应用的诊断标准，认知障碍的患病率和痴呆症的发病率存在重大差异。这些差异是由我们指出并讨论的方法学和理论缺陷所解释的（例如，参照组、缺乏诊断标准或排除标准、主观性程度高）。除了这些批评之外，我们还讨论了为达到最佳识别标准需要应对的挑战。值得注意的是，应使用更具体的问卷/任务来测试轻度认知障碍对日常生活活动的影响。认知障碍客观定义的目标应该是尽量减少诊断中的主观性。还建议在认知的所有方面使用敏感的认知测量方法，同时识别并考虑所有混杂因素（例如，年龄、教育水平）。鉴于轻度认知障碍的性质和后果，建议采用跨学科方法（例如，神经生物学、精神病学和遗传学线索）。就最佳诊断标准达成共识对于提出有效的痴呆症预防认知和药物治疗至关重要。
