ABSTRACT
According to a recent report from the National Institute of Population and Social Security Research (2002), the proportion of people aged over 65 years was 17.4% of the total Japanese population in 2000. It is estimated that this proportion will rise to 22% in 2010, and 28% in 2030 (Figure 5.1). This percentage, in particular, that of the old-old population, is expected to increase at the highest speed in the world until the year 2020. The number of the aged with dementia will increase concomitantly (Figure 5.2) (Otsuka, 2001). Approximately 70% to 80% of the aged with dementia are living in the community (Karasawa, 1988). Local governments in Japan have been greatly concerned with the various problems of the aged because of the rapid increase in their number, and they have investigated living conditions and the need for welfare services, especially for disabled elderly persons with dementia. In the last two decades, 45 surveys on dementia in the community have been conducted in Japan. Methodological features of epidemiological surveys on dementia and some recent results showing changing prevalence rates of vascular dementia will be described here.
