Hypertension has been variously defined over the years. However, systolic (i.e., peak) blood pressure ≥140 mmHg and diastolic blood pressure ≥90 mmHg are now considered indicative of hypertension and of meriting treatment. Blood pressure ca 120/80 mmHg is deemed to be normal (normotensive). Although hypertension may be a secondary consequence of problems elsewhere, e.g., renal failure, the vast majority of cases of hypertension have no proximal and discrete cause. This is called essential hypertension and is a major focus of research in behavioral medicine. This is easy to understand given the prevalence and health consequences of hypertension. It is estimated to affect 15% and 20% of the adult population in Western countries, with worldwide prevalence being around 10%. Concern with hypertension also reflects its association with coronary heart disease and stroke; the results of many studies testify that as blood pressure rises, life expectancy decreases. For example, at the outset of the famous Framingham study, some 5000 of the citizens of that small community in the USA had their blood pressures recorded; around 20% of them were hypertensive. Those with hypertension were three times more likely to go on to have a heart attack and eight times more likely to have a stroke. Given the clinical importance of hypertension, it is perhaps hardly surprising that there are several dedicated scientific journals and many texts devoted to hypertension. My favorite, however, remains Beevers and MacGregor (1995).
References and Further Reading
- Beevers, D. G., & MacGregor, G. A. (1995). Hypertension in practice (2nd ed.). London: Martin Dunitz.Google Scholar