Demographic, phenotypic, and genetic characteristics of centenarians in Okinawa and Honshu, Japan: Part 2 Honshu, Japan.

The scope and purpose of this review was to summarize the aims, methods, findings, and future of centenarian and (semi)-supercentenarian studies in Japan, particularly those from our own interdisciplinary laboratory. Medically, approximately 97% of centenarians contract chronic diseases including hypertension and gastrointestinal disease; however, they present with few cardiovascular risk factors. The low prevalence of diabetes mellitus and carotid atherosclerotic plaques is peculiarities of centenarians, which could be associated with high adiponectin levels. While conducting the Tokyo centenarian study (TCS), we found that only 20% of centenarians enjoyed physical and cognitive independence at the age of 100 years, although most remained independent in daily living until into their 90s. Those who maintained physical independence at 100 years of age were highly likely to become semi-supercentenarians (over 105 years) or even supercentenarians (beyond 110 years). We also describe parts of results of the Japan Semi-supercentenarian Study (JSS), which showed that the suppression of chronic inflammation is an important driver of successful aging at extreme old age. Telomere maintenance and an extremely low frequency of APOE-ε4 alleles are genetic peculiarities of (semi)-supercentenarians. The available data confirm our conviction that semi-supercentenarians are a more appropriate model for the study of human longevity.