Objective: This report presents estimates for the period 2001-2008 of means and selected percentiles of systolic and diastolic blood pressure by sex, race or ethnicity, age, and hypertension status in adults aged 18 and over.
Methods: Demographic characteristics were collected during a personal interview, and blood pressures were measured during a physician examination. All estimates were calculated using the mean of up to three measurements. The final analytic sample consisted of 19,921 adults aged 18 and over with complete data. Examined sample weights and sample design variables were used to calculate nationally representative estimates and standard error estimates that account for the complex design, using SAS and SUDAAN statistical software.
Results: Mean systolic blood pressure was 122 mm Hg for all adults aged 18 and over; it was 116 mm Hg for normotensive adults, 130 mm Hg for treated hypertensive adults, and 146 mm Hg for untreated hypertensive adults. Mean diastolic blood pressure was 71 mm Hg for all adults 18 and over; it was 69 mm Hg for normotensive adults, 75 mm Hg for treated hypertensive adults, and 85 mm Hg for untreated hypertensive adults. There was a trend of increasing systolic blood pressure with increasing age. A more curvilinear trend was seen in diastolic blood pressure, with increasing then decreasing means with age in both men and women. Men had higher mean systolic and diastolic pressures than women. There were some differences in mean blood pressure by race or ethnicity, with non-Hispanic black adults having higher mean systolic and diastolic blood pressures than non-Hispanic white and Mexican-American adults, but these differences were not consistent after stratification by hypertension status and sex.
Conclusions: These estimates of the distribution of blood pressure may be useful for policy makers who are considering ways to achieve a downward shift in the population distribution of blood pressure with the goal of reducing morbidity and mortality related to hypertension.