Pohjasvaara T, Erkinjuntti T, Vataja R, Kaste M
Department of Neurology, University of Helsinki, Finland.
Stroke. 1997 Apr;28(4):785-92. doi: 10.1161/01.str.28.4.785.
Vascular dementia is a common cause of dementia, and cerebrovascular disease is related to a higher risk of dementia. The frequency of dementia associated with ischemic stroke and the effects of different definitions of dementia in the diagnosis are still incompletely known. We evaluated the frequency of cognitive decline and dementia 3 months after ischemic stroke in a large stroke cohort.
Our cohort consisted of consecutively admitted ischemic stroke patients (n = 486) aged 55 to 85 years in the Helsinki (Finland) Stroke Aging Memory Study (SAM). Subjects were assessed by structured medical, neurological, and radiological examinations and interview with a close informant, as well as by the Mini-Mental State Examination and detailed clinical mental status examination of defined cognitive domains. The criteria for dementia were those of the Diagnostic and Statistical Manual of Mental Disorders (DSM) (DSM-III, DSM-III-R, and DSM-IV), the National Institute of Neurological Disorders and Stroke-Association Internationale pour la Recherche et l'Enseignement en Neurosciences (NINDS-AIREN), and the International Classification of Diseases, 10th Revision (ICD-10).
We found that 451 (92.8%) of the patients were testable, 239 (49.2%) of the patients were women, and the mean age was 71.2 years. Any cognitive decline was present in 61.7%. In the groups aged 55 to 64, 65 to 74, and 75 to 85 years, the frequency of any cognitive decline was 45.7%, 53.8%, and 74.1% (P = .0008), respectively. The frequency of dementia was 25.5% by DSM-III, 20.0% by DSM-III-R, 18.4% by DSM-IV, 21.1% by NINDS-AIREN, and 6.0% by ICD-10 criteria. The frequency increased with increasing age: by the DSM-III definition, frequency in the aforementioned age groups was 19.3%, 23.7%, and 25.5%, respectively (P = .014). There was an overlap in the cases diagnosed as demented according to the different guidelines. Compared with standard diagnosis, the DSM-III was the most sensitive and ICD-10 the most specific. Concordance was moderate between the DSM criteria and NINDS-AIREN criteria but was poor between ICD-10 and the other criteria.
Cognitive decline and dementia were frequent in the cohort of ischemic stroke patients, and the frequency increased with increasing age. Different definitions gave different frequency estimates, and overlap in the cases was observed. Our findings question the validity of current criteria for dementia in the setting of cerebrovascular disease and emphasize the need for further debate and studies to refine the categories of cognitive impairment related to cerebrovascular disease.
血管性痴呆是痴呆的常见病因，脑血管疾病与痴呆风险升高相关。缺血性卒中相关痴呆的发生率以及不同痴呆定义在诊断中的影响仍不完全清楚。我们在一个大型卒中队列中评估了缺血性卒中3个月后认知功能下降和痴呆的发生率。
我们的队列由赫尔辛基（芬兰）卒中、衰老与记忆研究（SAM）中连续收治的486例年龄在55至85岁的缺血性卒中患者组成。通过结构化的医学、神经学和放射学检查以及与密切知情者的访谈对受试者进行评估，同时采用简易精神状态检查表以及对特定认知领域进行详细的临床精神状态检查。痴呆的诊断标准采用《精神疾病诊断与统计手册》（DSM）（DSM - III、DSM - III - R和DSM - IV）、美国国立神经疾病与卒中研究所 - 国际神经科学研究与教育协会（NINDS - AIREN）以及《国际疾病分类》第10版（ICD - 10）的标准。
我们发现451例（92.8%）患者可进行测试，其中239例（49.2%）为女性，平均年龄为71.2岁。61.7%的患者存在任何认知功能下降。在55至64岁、65至74岁和75至85岁年龄组中，任何认知功能下降的发生率分别为45.7%、53.8%和74.1%（P = 0.0008）。按照DSM - III标准，痴呆发生率为25.5%；按照DSM - III - R标准为20.0%；按照DSM - IV标准为18.4%；按照NINDS - AIREN标准为21.1%；按照ICD - 10标准为6.0%。发生率随年龄增长而升高：按照DSM - III定义，上述年龄组的发生率分别为19.3%、23.7%和25.5%（P = 0.014）。根据不同指南诊断为痴呆的病例存在重叠。与标准诊断相比，DSM - III最敏感，ICD - 10最具特异性。DSM标准与NINDS - AIREN标准之间的一致性中等，但ICD - 10与其他标准之间的一致性较差。
缺血性卒中患者队列中认知功能下降和痴呆很常见，且发生率随年龄增长而升高。不同定义给出了不同的发生率估计，并且观察到病例存在重叠。我们的研究结果对脑血管病背景下当前痴呆标准的有效性提出了质疑，并强调需要进一步开展辩论和研究以完善与脑血管病相关的认知障碍分类。
