BACKGROUND: There have been no reports on the prevalence of dementia among the old-old people in Japan. METHODS: We studied the old-old population in Kurihara, northern Japan. Analysis 1 of Participants 1 (n=590) was performed to evaluate the prevalence of dementia and dementing diseases by intensive evaluation including MRI. Analysis 2 aimed to determine a good indicator for detecting 'suspected dementia condition' based on the Long-Term Care Insurance index. Analysis 3 of Participants 2 (n=3915) aimed to estimate the prevalence of 'suspected dementia condition'. RESULTS: In Analysis 1, 73 people (12.4%) were diagnosed with dementia. The most common cause was Alzheimer's disease with cerebrovascular disease. In Analysis 2, level I of the Impairment Level of Dementia was found to be a good indicator of 'suspected dementia condition'. In Analysis 3, the overall estimated prevalence of 'suspected dementia condition' was 23.6%. In men, the ratio increased gradually from 75 to 87 years old to about 20%, increased to 40% at the age of 88 and became stable thereafter. In contrast, in women, the ratio increased from 75 to 95+ years old, reaching about 70%. CONCLUSIONS: The prevalence was higher than that reported previously. There was a difference between the sexes: an 'age-related' increase occurred in men and an 'ageing-related' increase in women. Alzheimer's disease with cerebrovascular disease was the most common cause, which coincided with the previous findings of individuals aged 65 years and older; however, the ratio of mixed dementia was greater.
BACKGROUND: There have been no reports on the prevalence of dementia among the old-old people in Japan. METHODS: We studied the old-old population in Kurihara, northern Japan. Analysis 1 of Participants 1 (n=590) was performed to evaluate the prevalence of dementia and dementing diseases by intensive evaluation including MRI. Analysis 2 aimed to determine a good indicator for detecting 'suspected dementia condition' based on the Long-Term Care Insurance index. Analysis 3 of Participants 2 (n=3915) aimed to estimate the prevalence of 'suspected dementia condition'. RESULTS: In Analysis 1, 73 people (12.4%) were diagnosed with dementia. The most common cause was Alzheimer's disease with cerebrovascular disease. In Analysis 2, level I of the Impairment Level of Dementia was found to be a good indicator of 'suspected dementia condition'. In Analysis 3, the overall estimated prevalence of 'suspected dementia condition' was 23.6%. In men, the ratio increased gradually from 75 to 87 years old to about 20%, increased to 40% at the age of 88 and became stable thereafter. In contrast, in women, the ratio increased from 75 to 95+ years old, reaching about 70%. CONCLUSIONS: The prevalence was higher than that reported previously. There was a difference between the sexes: an 'age-related' increase occurred in men and an 'ageing-related' increase in women. Alzheimer's disease with cerebrovascular disease was the most common cause, which coincided with the previous findings of individuals aged 65 years and older; however, the ratio of mixed dementia was greater.
Authors: Hiroyuki Hikichi; Jun Aida; Katsunori Kondo; Toru Tsuboya; Yusuke Matsuyama; S V Subramanian; Ichiro Kawachi Journal: Proc Natl Acad Sci U S A Date: 2016-10-24 Impact factor: 11.205
Authors: Joe Verghese; Cedric Annweiler; Emmeline Ayers; Nir Barzilai; Olivier Beauchet; David A Bennett; Stephanie A Bridenbaugh; Aron S Buchman; Michele L Callisaya; Richard Camicioli; Benjamin Capistrant; Somnath Chatterji; Anne-Marie De Cock; Luigi Ferrucci; Nir Giladi; Jack M Guralnik; Jeffrey M Hausdorff; Roee Holtzer; Ki Woong Kim; Paul Kowal; Reto W Kressig; Jae-Young Lim; Susan Lord; Kenichi Meguro; Manuel Montero-Odasso; Susan W Muir-Hunter; Mohan L Noone; Lynn Rochester; Velandai Srikanth; Cuiling Wang Journal: Neurology Date: 2014-07-16 Impact factor: 9.910