Fisk J D, Rockwood K
Division of Geriatric Medicine, Department of Medicine, Dalhousie University, Halifax, NS, Canada.
J Neurol Neurosurg Psychiatry. 2005 Aug;76(8):1175-7. doi: 10.1136/jnnp.2004.053751.
Definitions of mild cognitive impairment (MCI) vary, yielding conflicting results. For example, case definitions affect prevalence but not outcomes in prevalent cases. Our objective was to determine whether variation in case definitions affects outcomes in incident cases of MCI. The 5 year risks of death, institutionalisation, and dementia were evaluated in clinically examined incident MCI cases in the Canadian Study of Health and Aging. The definition of MCI was varied so as to include or relax combinations of diagnostic features from consensus criteria. Relative risks (RR) of each adverse outcome were highest in MCI case definitions that required subjective memory complaints (for example, RR of dementia = 26.4-38.7). Although each MCI definition conferred an increased risk of dementia, for each case definition 20-30% of survivors had no cognitive impairment at follow up. In this population based study, MCI represented a transitional state, but was heterogeneous, with substantial proportions recovering, regardless of how MCI was defined. Factors associated with recovery and non-progression in MCI require elucidation.
轻度认知障碍（MCI）的定义各不相同，导致结果相互矛盾。例如，病例定义会影响患病率，但对现患病例的预后没有影响。我们的目标是确定病例定义的差异是否会影响MCI新发病例的预后。在加拿大健康与老龄化研究中，对经过临床检查的MCI新发病例的5年死亡、入住机构和患痴呆症风险进行了评估。MCI的定义有所不同，包括或放宽了共识标准中的诊断特征组合。在需要主观记忆主诉的MCI病例定义中，每种不良后果的相对风险（RR）最高（例如，痴呆症的RR = 26.4 - 38.7）。虽然每种MCI定义都增加了患痴呆症的风险，但对于每种病例定义，20% - 30%的幸存者在随访时没有认知障碍。在这项基于人群的研究中，MCI代表一种过渡状态，但具有异质性，无论MCI如何定义，都有相当比例的人恢复了。MCI中与恢复和不进展相关的因素需要阐明。
