Ebly E M, Parhad I M, Hogan D B, Fung T S
Department of Pathology, University of Calgary, AB, Canada.
Neurology. 1994 Sep;44(9):1593-600. doi: 10.1212/wnl.44.9.1593.
We report on the prevalence of dementia in Canadians age 85 years and older. The purpose of this study was to determine whether the prevalence of dementia continued to increase in the very old, and to define the types of dementia and their relative proportions in this age group. We collected data as part of the Canadian Study of Health and Aging (1990 to 1992), which consisted of a sample of 1,835 subjects from a population of 283,510 Canadians who were 85 years of age and older residing in the community or in institutions. The prevalence of dementia in the 85 years and older group was 28.5%, more than twice that of the 75- to 84-years cohort. The prevalence of dementia of 23% in the 85- to 89-years sample (n = 1,332) increased to 40% in the 90 to 94 years group (n = 371) and, in the 95 years and older sample (n = 104), reached 58%. Overall, Alzheimer's disease (AD; probable or possible) accounted for 75% of all dementias; a vascular etiology alone accounted for 13% of dementias. The proportion of clinically diagnosed AD cases to vascular dementia cases increased significantly after age 65 and was higher in the 85+ group than in a younger cohort (65 to 84 years).
我们报告了85岁及以上加拿大人群中痴呆症的患病率。本研究的目的是确定在高龄人群中痴呆症的患病率是否持续上升，并明确该年龄组痴呆症的类型及其相对比例。我们收集的数据是加拿大健康与老龄化研究（1990年至1992年）的一部分，该研究从283,510名居住在社区或机构中的85岁及以上加拿大人中抽取了1,835名受试者作为样本。85岁及以上组痴呆症的患病率为28.5%，是75至84岁队列患病率的两倍多。85至89岁样本（n = 1,332）中痴呆症的患病率为23%，在90至94岁组（n = 371）中升至40%，在95岁及以上样本（n = 104）中达到58%。总体而言，阿尔茨海默病（AD；可能或疑似）占所有痴呆症的75%；单纯血管病因导致的痴呆症占13%。65岁以后临床诊断的AD病例与血管性痴呆病例的比例显著增加，且在85岁以上组高于较年轻队列（65至84岁）。
