Cardiovascular disease, a major global burden: Epidemiology of stroke and ischemic heart disease in Japan

Abstract

Japan ranks the highest globally, in terms of longevity. The average life expectancy was 81.4 years for men and 87.5 years for women in 2019. Such success in health is attributable to the substantial reduction in age-standardized mortality from cardiovascular diseases, especially stroke (136 per 10⁵ in 1980 and 24 per 10⁵ in 2015), when stroke mortality was the highest in the world between the 1960s and the 1990s. On the other hand, ischemic heart disease mortality was the lowest in the world between the 1960s and the 1980s and has continued to decline (40 per 10⁵ in 1980 and 17 per 10⁵ in 2015). Such a disease profile (larger burden of stroke compared to ischemic heart disease) was observed not only in Japan but also in some countries in central Asia and Africa, where small vessel disease (arteriolosclerosis) is assumed to be more common than large vessel disease (atherosclerosis). Between 1970 and 2015, a large decline in the population with high blood pressure levels was observed for both men and women. Meanwhile, there was a moderate decline in the smoking rate among men, and an increasing trend in serum cholesterol levels in both men and women. The sharp and extensive socioeconomic development between the 1960s and 1990s contributed to these health outcomes, while preventive measures and improved emergency medical care also contributed to the reduction of risk factors, disease incidence, case-fatality, and mortality. However, there is a threat of increasing incidence of ischemic heart disease in urban male employees and middle-aged male residents. Japan, with a super-aging society, needs to develop a new model for the prevention and control of cardiovascular disease and related health issues, with emphasis on efforts towards the early (primordial) prevention of cardiovascular disease as well as the attenuation of their progress towards chronic heart failure, chronic kidney disease, and vascular dementia.

Keywords: Japan; cardiovascular disease; epidemiology; pathology; prevention.

Figure 1.

Age- and sex-adjusted mortality rate per 100,000, standardized to the standard WHO population, from stroke (A), ischemic heart disease (B), and stroke relative to ischemic heart disease. Source: Reference 2.

Figure 2.

Two types of vascular pathology and related factors, atherosclerosis and arteriolosclerosis. Source: References 7.

Figure 3.

Sex- and age-specific trends for systolic blood pressure levels between 1970 and 2019. Source: National Health and Nutrition Survey, Reference 18.

Figure 4.

Sex-specific trends for age-adjusted mortality rates per 10,000, standardized to the 1960 Japan national standard population, for stroke between 1960 and 2019. Source: Reference 19.

Figure 5.

Sex-specific trends for cardiovascular risk factors such as mean levels of systolic blood pressure (A), body mass index (B), serum total cholesterol (C), and smoking rate (D) in national samples of Japan and the US between 1960 and 2019.

Figure 6.

Sex- and age-adjusted 8-year incidence per 1,000 of stroke (A) and incremental cost (yen per capita) (B) in the full intervention versus minimum intervention communities from 1964 to 1987. Source: References 21, 24.