Trends in Prehypertension and Hypertension Risk Factors in US Adults: 1999-2012

Abstract

Prehypertension is associated with increased risk for hypertension and cardiovascular disease. Data are limited on the temporal changes in the prevalence of prehypertension and risk factors for hypertension and cardiovascular disease among US adults with prehypertension. We analyzed data from 30 958 US adults ≥20 years of age who participated in the National Health and Nutrition Examination Surveys between 1999 and 2012. Using the mean of 3 blood pressure (BP) measurements from a study examination, prehypertension was defined as systolic BP of 120 to 139 mm Hg and diastolic BP <90 mm Hg or diastolic BP of 80 to 89 mm Hg and systolic BP <140 mm Hg among participants not taking antihypertensive medication. Between 1999-2000 and 2011-2012, the percentage of US adults with prehypertension decreased from 31.2% to 28.2% (P trend=0.007). During this time period, the prevalence of several risk factors for cardiovascular disease and incident hypertension increased among US adults with prehypertension, including prediabetes (9.6% to 21.6%), diabetes mellitus (6.0% to 8.5%), overweight (33.5% to 37.3%), and obesity (30.6% to 35.2%). There was a nonstatistically significant increase in no weekly leisure-time physical activity (40.0% to 43.9%). Also, the prevalence of adhering to the Dietary Approaches to Stop Hypertension eating pattern decreased (18.4% to 11.9%). In contrast, there was a nonstatistically significant decline in current smoking (25.9% to 23.2%). In conclusion, the prevalence of prehypertension has decreased modestly since 1999-2000. Population-level approaches directed at adults with prehypertension are needed to improve risk factors to prevent hypertension and cardiovascular disease.

Keywords: blood pressure; exercise; nutrition surveys; prehypertension; prevention; risk factors; trend.

Figure 1

Age-adjusted percentage (top panel) and unadjusted number (bottom panel) of United States adults aged ≥ 20 years with normal blood pressure, prehypertension and hypertension by National Health and Nutrition Examination Survey (NHANES) by calendar year. Normal blood pressure: systolic blood pressure < 120 mmHg and diastolic blood pressure < 80 mmHg without antihypertensive medication use. Prehypertension: systolic blood pressure 120–139 mmHg with diastolic blood pressure < 90 mmHg or diastolic blood pressure 80–89 mmHg with systolic blood pressure < 140 mmHg without antihypertensive medication use. Hypertension: systolic blood pressure ≥ 140 mmHg or diastolic blood pressure ≥ 90 mmHg and/or antihypertensive medication use.

Figure 2

Age-adjusted percentage of United States adults aged ≥ 20 years with normal blood pressure (left column), prehypertension (middle column) and hypertension (right column) from 1999–2000 through 2011–2012 by age, race/ethnicity and sex. US: United States. Arrows indicate the prevalence corresponding with Non-Hispanic Whites, Non-Hispanic Blacks or Hispanics where the plotted values for these race/ethnic groups are difficult to distinguish. The age-adjusted percentage of United States adults aged ≥ 20 years with normal blood pressure, prehypertension and hypertension from 1999–2000 through 2011–2012 overall is reported in Table S1. Also, the 95% confidence interval corresponding with each point estimate in the current figure, p-trend representing the change in the prevalence over calendar period and the p-interaction representing differences in the change in the prevalence over calendar period across age, race/ethnicity and sex sub-groups is reported in Table S1.

Figure 3

Age-adjusted percentage of United States adults aged ≥ 20 years with prehypertension in US adults without normal blood pressure (left column) and without hypertension (right column) by National Health and Nutrition Examination Survey (NHANES) calendar year overall and by age, race/ethnicity and sex. Arrows indicate the prevalence corresponding with Non-Hispanic Whites, Non-Hispanic Blacks or Hispanics where the plotted values for these race/ethnic groups are difficult to distinguish. The 95% confidence interval corresponding with each point estimate, p-trend representing the change in the prevalence over calendar period and the p-interaction representing differences in the change in the prevalence over calendar period across age, race/ethnicity and sex sub-groups is reported in Table S2.