Trends in the Incidence of Cardiovascular Disease and the Treatment of Hypertension in Japan

Abstract

Over the past two decades there has been a precipitous fall in the age-adjusted rate of deaths due to cerebrovascular disease in Japan, while the rate of deaths due to heart disease has fallen only slightly. Mortality from heart disease since 1984 has been greater than that from cerebrovascular disease. However, an epidemiologic survey in Okinawa indicates that the incidence of stroke is 4.4times higher than that of acute myocardial infarction: the average age-adjusted annual incidences of stroke and acute myocardial infarction per 100, 000 people aged 40years and older were 315 and 72, respectively. The National Nutrition Survey and National Survey on Circulatory Disorders revealed that during the last 10 years the averages of systolic and diastolic blood pressures of Japanese decreased, especially in those aged 50 and older, and the prevalence of hypertension as well as of left ventricular hypertrophy diagnosed by electrocardiography decreased significantly in both men and women. This may be attributable to widespread education concerning hypertension and antihypertensive treatment. However, the average serum total cholesterol concentration increased by 12mg/dl in men and 16mg/dl in women and the prevalence of hypercholesterolemia increased in both men and women during the last 10years. Furthermore, 61% of men still smoke. Research results show that the mortality and morbidity rates for cardiovascular diseases are changing in Japan. This seems to be related to the fact that Japanese people are adopting a more westernized pattern of food intake. There is a concern that the incidence of acute myocardial infarction might greatly increase in the near future. (Hypertens Res 1994; 17: 215-219)