American Journal of Hypertension 1 Original article

It is well known that blood pressure (BP) in the prehyperten-sive range, defined by the Joint National Committee on the Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC 7) as a systolic BP (SBP) of 120–139 mm Hg and/or a diastolic BP (DBP) of 80–89 mm Hg, is associ-ated with the future development of frank hypertension (HTN).1–5 But what is less well understood are the cardiovas-cular risks conferred by prehypertension, before frank HTN is manifest. It remains controversial whether prehyperten-sion alone or higher BP within the prehypertensive range is independently associated with coronary heart disease (CHD) risk or whether any observed increased risk is the result of associated risk factors. In 1 report, 64 % of prehypertensive subjects had>1 cardiovascular disease (CVD) risk factor.6 Several studies have reported on the CHD risk of pre-hypertension. Manious et al. analyzed participants in the first National Health and Nutrition Examination Survey (1971–1975) and ascertained major CVD events over the next 18 years.7 They divided prehypertension into cat-egories, “low prehypertension ” (120–129/80–84 mm Hg) and “high prehypertension ” (130–139/80–89 mm Hg), and found that unadjusted analysis demonstrated risk for both groups but adjustment attenuated the statistical significance of the risk in the low prehypertension (unad-justed hazard ratio (HR) = 1.56, 95 % confidence interval (CI) = 1.23–1.98; adjusted HR = 1.24, 95 % CI = 0.96–1.59) but not in the high prehypertension group (unadjusted HR = 2.12, 95 % CI = 1.64–2.76; adjusted HR = 1.42, 95% CI = 1.09–1.84).7 In the Framingham Heart Study, BP lev-els of 130–139/85–89 mm Hg were associated with twice the risk of CVD compared with BP levels <120/80 mm Hg.4 In the past decade, overall CVD events have significantl