Prevalence, awareness, treatment and control of hypertension in North America, North Africa and Asia.

Results from national surveys of prevalence, awareness, treatment and control provide the most meaningful basis for assessing the burden of hypertension in the community. National surveys conducted in a variety of countries in North America, Europe, Australia, Asia and Africa have identified a strikingly similar relationship between age and blood pressure (BP), with a progressive and steep increase in systolic BP throughout adult life and a less steep increase in diastolic BP from adolescence until the fifth or sixth decade. In most countries surveyed, there was a high prevalence of hypertension. Approximately, one quarter of all adults in the United States and Egypt had hypertension (systolic BP>/=140 mmHg or diastolic BP>/=90 mmHg or use of antihypertensive medication) in national surveys conducted in 1988-1991 and 1991-1993, respectively. The corresponding percentage was somewhat lower (14.4%) for adults surveyed in China during 1991, but temporal trends indicate that the prevalence of hypertension is increasing rapidly in that country. In the 1988-1991 national survey, more than 25% of US adults were unaware of their diagnosis, only 55% were being treated with antihypertensive medication and only 29% were on antihypertensive medication with a systolic/diastolic BP >140/90 mmHg. The situation was much worse in Egypt and China, with only 8% and <5% of adults with hypertension, respectively, being treated with antihypertensive medication and having a systolic/diastolic BP <140/90 mmHg. These survey results underscore the fact that hypertension is highly prevalent, poorly treated and controlled, and an escalating health challenge in economically developing countries.