■ Abstract Hypertension is the leading cause of cardiovascular disease worldwide.Prior to 1990, population data suggest that hypertension prevalence was decreasing; however, recent data suggest that it is again on the rise. In -2002.6% of the U.S. population had hypertension. Hypertension prevalence has also been increasing in other countries, and an estimated 972 million people in the world are suffering from this problem. Incidence rates of hypertension range between 3% and 18%, depending on the age, gender, ethnicity, and body size of the population studied. Despite advances in hypertension treatment, control rates continue to be suboptimal. Only about one third of all hypertensives are controlled in the United States. Programs that improve hypertension control rates and prevent hypertension are urgently needed.
DEFINING HYPERTENSIONThe definition of hypertension has changed over time in response to better understanding of the pathophysiology, actuarial considerations of the life insurance industry, studies of blood pressure in diverse populations, consideration of the interaction of blood pressure levels and comorbid conditions, landmark studies of blood pressure-related health outcomes, and the development and evaluation of effective antihypertensive therapies. Definitions for the upper level of normal ranges of blood pressure for adults have been based on epidemiological findings relating blood pressure levels to risks for adverse outcomes in populations and evidence from clinical trials demonstrating reduced risk of adverse outcomes with antihypertensive therapies.Epidemiological data support a continuous, incremental risk of cardiovascular disease, stroke, and renal disease across levels of both systolic and diastolic blood pressure (89,151,184). The life insurance industry was the first to relate mortality