※ Currently, participation recruitment and follow-up survey are both closed.
People over the age of 100 are called centenarians. Many centenarians live independently the majority of their lives, which is considered to be a model of healthy longevity. Our research is exploring the secrets to healthy longevity by clarifying the biomedical characteristics of centenarians, lifestyle habits, cognitive factors regarding personality and approach to life, and even genetic features.
We began researching centenarians at Keio University School of Medicine in 1992. At the beginning, only medical doctors in the Division of Geriatric Medicine were engaged in the visit survey of centenarians. It was possible to investigate only 20–30 people per year. Since 2000, in collaboration with the Tokyo Metropolitan Institute of Gerontology, we initiated the Tokyo Centenarian Study (TCS). In this survey, we randomly selected 1,194 people living in 23 wards of Tokyo between 2000 and 2002 from the basic resident registry, and sent a letter of invitation to participate in this research. A total of 514 people completed the questionnaire survey, and 304 participated in the medical psychology investigations.
In the TCS, doctors and nurses at Keio University Hospital and researchers at the Tokyo Metropolitan Institute of Gerontology assembled an expert team to visit centenarians home by home, surveying health condition, cognitive function, character and eating habit; participants also underwent blood tests. From this research, we determined various characteristics of the centenarians.
- Most suffered from one or more chronic disease(s) or had a history of chronic disease
- There was a high frequency of high blood pressure, cataract, and fractures (especially in female centenarians)
- Prevalence of diabetes was low
- Approximately 20% of centenarians maintained independent ADL
Based on the TCS, we noticed that those with higher ADL tended to live longer than 105 years. Therefore, in 2002, we started a new nationwide study focused on semi-supercentenarians (SSC; those 105 years old or older) with a long period of independent life (= healthy life expectancy).