Epidemiology of Hypertension and Cardiovascular DiseaseHypertension is the most common chronic medical disorder in theUnited States. According to JNC 7 criteria, more than 65 millionAmericans have hypertension and an additional 25% of the populationhas prehypertension. 1 Despite its vast prevalence, hypertensionremains highly under recognized with a full 30% of patientsunaware that they have the condition.In developed societies, blood pressure increases with age.Diastolic BP plateaus in the fifth decade and may decline thereafterbut systolic BP continues to rise steadily through the seventhdecade. The Framingham Heart Study estimated the 20-year riskof developing hypertension as >90% for normotensive men andwomen of middle age (55–65 years of age). 2 Among Americansover age 65, more than half have isolated systolic or combinedsystolic-diastolic hypertension.