Cardiovascular disease is now endemic worldwide and no longer limited to economically developed countries [1]. In developed countries, cardiovascular disease accounts for about 35% of all deaths. Similar rates, but among younger age groups, are now being seen in developing countries such as Tanzania and India. Strategies to combat this growing burden are logically directed at cardiovascular risk factors, in particular blood pressure.
It has been estimated that worldwide in 2001, 7.6 million premature deaths were attributable to high blood pressure [2]. By the year 2025, hypertension is expected to increase in prevalence by 60%, affecting 1.56 billion people, with an 80% increase (from 639 million to 1.15 billion) in economically developing nations. In terms of cardiovascular disease, high blood pressure accounted for 54% of stroke and 47% of ischemic heart disease globally. This makes high blood pressure the most important cardiovascular risk factor. It was also noted that half of this burden was in people with hypertension; the remainder was in those with lesser degrees of high blood pressure.
The late Geoffrey Rose made the point that there is a continuous relationship between blood pressure and cardiovascular risk [3]. Even people with average levels of blood pressure have higher risks than those with the lowest pressures. If one multiplies the number of people with average pressure by the risk associated with such a pressure, one finds that average pressure accounts for more cardiovascular deaths than can be attributed to the fewer individuals with the highest pressure levels[4]. Herein lies a paradox. The medical profession identifies and treats only patients with hypertension. Population "treatment" has been the domain of public health where dietary and lifestyle measures are promoted population-wide to reduce blood pressure generally. Why don't doctors extend their treatments to people with normal blood pressures if it is this group that most cardiovascular deaths occur?
