Blood pressure and high blood pressure. Aspects of risk.

This report deals with three aspects of risk related to blood pressure and high blood pressure. The first aspect of risk concerns distributions of systolic blood pressure (SBP) and diastolic blood pressure (DBP) in the adult population and their relation to long-term risk of morbidity and mortality. By middle age, only a minority (about 20%) of Americans have optimal SBP and DBP levels, less than 120 mm Hg and less than 80 mm Hg, respectively. For the majority with higher levels, risks of major clinical events, including death from cardiovascular diseases and from all causes, are markedly increased. The relations of SBP and DBP with risk are strong, continuous, and graded. Risk is sizable not only for persons with high blood pressure by usual clinical criteria (SBP greater than or equal to 140 mm Hg or DBP greater than or equal to 90 mm Hg), but also for those with "high-normal" blood pressure (e.g., SBP 130-139 mm Hg or DBP 80-89 mm Hg). Thus, the blood pressure problem is a population-wide one and requires for its control a combined population-wide and high-risk strategy. A major component of this strategy must be nutritional-hygienic measures for the primary prevention of the rise in blood pressure during adulthood and of high blood pressure (i.e., primary prevention not only of the complications of high blood pressure but also of high blood pressure itself) through improved lifestyles having the potential to shift downward the blood pressure distribution of the whole population. The second aspect of risk concerns the known risk factors (i.e., aspects of modern lifestyle) leading to the mass occurrence of blood pressure rise during adulthood and of high blood pressure. These risk factors are high salt intake, high dietary sodium/potassium ratio, calorie imbalance and resultant obesity, and high alcohol intake. The extensive data base establishing the role of these common traits in the etiology of the blood pressure/high blood pressure problem is the scientific foundation for efforts to achieve the primary prevention of high blood pressure. The third aspect of risk relates to the combined impact of other risk factors along with blood pressure-high blood pressure in markedly increasing the probabilities of morbidity and mortality (e.g., "rich" diet, diet-dependent serum cholesterol and uric acid, smoking, diabetes, and target-organ damage). Prevention and control of lifestyle-related traits are essential components of the strategy for dealing with the blood pressure-high blood pressure problem.