[Alteration of Lifestyle-Related Diseases in Japanese: Current Status and Challenges--the Hisayama Study].

Japan has the world's fastest aging society and is characterized by a rapid increase in the prevalence of metabolic disorders, such as obesity and diabetes mellitus, due to the westernization of the lifestyle. These situations might affect the risk of cardiovascular disease in Japanese. To overview the secular trends in the incidence of cardiovascular disease along with the prevalence of risk factors during the past half century in the general Japanese population, we established 5 cohorts consisting of residents aged ≥ 40 years in a community, Hisayama, in 1961(n = 1,618), 1974 (n = 2,038), 1983 (n = 2,459), 1993 (n = 1,983), and 2002 (n = 3,108), and followed up each cohort for 7 years. In both sexes, the age-adjusted incidence of ischemic stroke decreased markedly from the 1960s to 1970s, but this decreasing trend slowed down from the 1970s to 2000s, while the incidence of acute myocardial infarction did not change during this period. From the 1960s to 2000s, blood pressure control among hypertensive individuals improved significantly, and the smoking rate decreased, but the prevalence of glucose intolerance (prediabetes and diabetes), hypercholesterolemia, and obesity increased steeply. These changes in the incidence of cardiovascular disease probably occurred because the benefits of hypertension control and smoking cessation have been negated by increases in population aging and metabolic risk factors. In addition, the recent findings of the Hisayama study indicated that diabetes is a risk factor for the development of cancer and dementia, and the prevalence of the latter increased rapidly in the Japanese elderly.