Hypertension and stroke in Asia: prevalence, control and strategies in developing countries for prevention

Reliable statistics related to the prevalence, incidence and mortality of hypertension and stroke are not available from Asia. The data may be in national or institutional reports or journals published in the local language only. The mortality rate for stroke has been on the decline since the mid 1960s in the developed countries of Asia, such as Australia, New Zealand, and Japan, with some improvement in Singapore, Taiwan and Hong Kong, some areas of China and Malaysia about 15 years later. In India, China, Philippines, Thailand, Sri Lanka, Iran, Pakistan, Nepal, there has been a rapid increase in stroke mortality and prevalence of hypertension. The prevalence of hypertension according to new criteria (>140/90 mm Hg) varies between 15-35% in urban adult populations of Asia. In rural populations, the prevalence is two to three times lower than in urban subjects. Hypertension and stroke occur at a relatively younger age in Asians and the risk of hypertension increases at lower levels of body mass index of 23-25 kg/m2. Overweight, sedentary behaviour, alcohol, higher social class, salt intake, diabetes mellitus and smoking are risk factors for hypertension in most of the countries of Asia. In Australia, New Zealand and Japan, lower social class is a risk factor for hypertension and stroke. Population-based long-term follow-up studies are urgently needed to demonstrate the association of risk factors with hypertension in Asia. However prevention programmes should be started based on cross-sectional surveys and case studies without waiting for the cohort studies.