Behrman Sophie, Valkanova Vyara, Allan Charlotte L
Practitioner. 2017 May;261(1804):17-20.
There has been a rapid rise in the number of people diagnosed with dementia in England from 232,000 in 2008 to 850,000 in 2014. Currently, it is estimated that the prevalence of mild cognitive impairment in adults aged 65 and over is 10-20%. It is likely that this figure will increase in line with trends in dementia diagnosis. In some cases, mild cognitive impairment may be a prodrome for dementia, and my be caused by any of the dementia pathology subtypes. The relationship between depression in the elderly and mild cognitive impairment is difficult to tease out as they are frequently comorbid conditions and both have been found to be independent risk factors for subsequent dementia: about 10% convert to dementia each year, compared with 1-2% of the general elderly population. It is important to obtain a history of cognitive changes over time, as well as information about the onset and nature of cognitive symptoms, confirmed by a reliable informant, if available. To confirm the diagnosis objective evidence of cognitive impairment is required. However, there are no specific neuropsychological tests for patients with mild cognitive impairment. On neuropsychological tests, individuals with mild cognitive impairment typically score 1-15 SD below the mean for their age and education, although these ranges are guidelines and not cut-off scores. GPs should consider referring people who signs of mild cognitive impairment for assessment by specialist memory assessment services to aid early identification of dementia, because more than 50% of people with mild cognitive impairment later develop dementia.
在英格兰，被诊断患有痴呆症的人数迅速上升，从2008年的23.2万增至2014年的85万。目前估计，65岁及以上成年人中轻度认知障碍的患病率为10% - 20%。随着痴呆症诊断趋势的发展，这一数字可能会上升。在某些情况下，轻度认知障碍可能是痴呆症的前驱症状，可能由任何一种痴呆症病理亚型引起。老年人抑郁症与轻度认知障碍之间的关系难以梳理清楚，因为它们常常是共病情况，而且二者均被发现是后续痴呆症的独立风险因素：每年约10%的患者会转变为痴呆症，而普通老年人群的这一比例为1% - 2%。重要的是要获取随时间变化的认知改变病史，以及认知症状的起病情况和性质信息，如有可靠的知情者可予以证实。要确诊则需要认知障碍的客观证据。然而，对于轻度认知障碍患者没有特定的神经心理学测试。在神经心理学测试中，轻度认知障碍患者的得分通常比同年龄和受教育程度的人群平均得分低1 - 1.5个标准差，不过这些范围只是指导原则，并非临界分数。全科医生应考虑将有轻度认知障碍迹象的人转介给专业记忆评估服务机构进行评估，以帮助早期识别痴呆症患者，因为超过50%的轻度认知障碍患者后来会发展为痴呆症。
